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Commercial Structural Code Forum Questions & Answers

 

 

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Accessibility

Q:   There is widespread inconsistency in accessibility requirements. Some jurisdictions have issued accessibility interpretations while others don't even review accessibility details in the documents saying that this is a federal civil law.
A:  

The Building Official, by ORS 447, is responsible to enforce these provisions (Chapter 11) of the code. Therefore all jurisdictions should provide accessibility guidelines for plan review and provide comments to the applicant during the plan review process. Beginning Sept. 1, Tri-County jurisdictions are required to use the commercial application checklist and process. This process provides the opportunity for a pre-submittal meeting during which the jurisdiction can outline the accessibility requirements of the project, using the commercial application checklist as a guide.(September 6, 2001 Tri-County Building Code Forum)


Q:   Is it permissible to compare only base shear values for wind and earthquake loads to decide whether wind or seismic loads govern the design?
A:  

No, it is not permissible. A correct analysis requires determining both the earthquake loads and the wind loads on an element of a structure. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For an existing building being relocated with no interior remodel or change of use, what are the upgrade requirements by code?
A:  

Section 3404 of the OSSC addresses "moved buildings" as does ORS 455.410 entitled "Relocated Buildings; Substantial Compliance Required; Permits." The statute states that "existing buildings or structures which are removed from their foundation and relocated to another site within this state shall be in substantial compliance in accordance to the statute." In short, the statute recognizes moved buildings as existing structures. This statute defines "substantial compliance" and addresses upgrade requirements in terms of foundation construction, installation upgrades, smoke detection and permit requirements. The statute requires the new foundation to fully comply with current building codes. It also requires the ceiling and underfloor insulation to be upgraded to current levels. It requires the installation of smoke alarms at all locations the code imposes for new construction, but only requires the alarms to be hardwired and interconnected when wall and ceiling finishes have been removed, much like we see with residential alterations. The jurisdiction cannot require existing windows (or other elements) to be upgraded for reasons of energy code compliance or to meet egress requirements. The only time a jurisdiction can require upgrades is in the case where the moved structure is altered and then only those portions that are altered must be upgraded. For example, let's say an existing 3-bedroom dwelling is relocated to a new site. The plans show that the kitchen will be remodeled as will the master bedroom. The master bedroom shows a new window being installed but the other 2 bedrooms show no alterations. The Plans Examiner knows that the windows in the other 2 bedrooms have a sill height of greater than 44" above the finish floor and thus do not meet current code. Can the examiner require the master bedroom window to meet egress? Yes, because is it is "new" and not a part of the "existing" dwelling. Can the examiner require the windows in the other two bedrooms to be replaced? No, because they are existing.

(September 6, 2001 Tri-County Building Code Forum)


Q:  

There are some jurisdictions in the Tri-County area that accept single user, unisex toilettes in "A" occupancy while others don't.


Background: When this issue is not resolved until building permit application time, it is very difficult to resolve in a building that has been fully designed.

A:  

Section 101.3 (Scope) incorrectly identifies Appendix Chapter 29 as being adopted. When the code was last modified, provisions of the appendix chapter were brought forward to the regular chapter eliminating the need for the appendix chapter. However, Table 29-A is adopted by reference in Section 2902.2. To be clear, only Table 29-A is adopted. That said, occupancies are required to have restrooms in the number determined by Chapter 29 and Table 29-A. Section 1108.2.2 imposes an additional requirement that an accessible, unisex toilet facility be provided where an aggregate of six or more male and female water closets are required in "A" occupancies, recognizing that in larger facilities it is likely that a disabled person might require assistance by a member of the opposite sex. In "M" occupancies, the required number of toilets may be much lower; in fact, a single-occupant unisex accessible restroom might fulfill all code requirements. Finally, in existing facilities, where it is impractical to fully comply with the code, Section 1113.3.7.1 may be invoked. This section allows one unisex facility in lieu of making existing facilities accessible. See 2904.2, which deals with the substantial alteration of existing Group A occupancies. The building official may approve substantial alterations without the installation of additional water closets only where it is structurally unfeasible to make such alterations. (September 6, 2001 Tri-County Building Code Forum)


Q:  

In a multistory rated building some jurisdictions require a "lid" on the bottom side of a private balcony while others do not.


Background: This typically occurs in a Type-V One-Hour, R-1 occupancy and multistory buildings where there are unit balconies that stack. It is generally agreed that even when using pressure treated materials, enclosing these decks on the underside will rapidly lead to deterioration in our moist climate. Venting these areas on the horizontal surface is not permitted in the code. Face vents are problematic. This issue regards conventional construction and not the use of heavy timber. It also deals specifically with private balconies, not exterior exit balconies.

A:  

Section 705 (Projections) speaks to architectural appendages beyond the floor area and thus applies to exterior balconies. Projections from Type-V construction may be of combustible or noncombustible construction. These projections are only required to be protected with one-hour fire resistive construction where openings are required to be protected or where they are prohibited. Therefore, balconies (other than exterior exit balconies) can be of unprotected construction. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do older buildings require seismic upgrading?
A:  

Portland has an ordinance requiring the seismic upgrading of un-reinforced masonry buildings that the City has specifically listed. Nothing in the code mandates such upgrades, but the code does give guidance about providing the upgrades. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Can a uniform commercial re-roofing permit and procedure be developed for tri-county area?
A:  

Mr. Watts with Associated Roofing Contractors posed this question. He represents commercial roofing companies in the tri-county region. The roofing association would like consistency and a uniform approach to handling re-roofing projects in the tri-county area. Mr. Watts mentioned some jurisdictions require engineering reports and some do not and noted that consistency also varies among jurisdictions regarding pre-inspections.

The panel forwarded this issue to the Tri-County Processes and Forms committee for discussion and action. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   What occupancy classification should be assigned to a dining/drinking establishment that contains more than one room each with an occupant load of 49 or less but with a total combined occupant load exceeding 50 and with room having one code compliant exit? Are there any restrictions on how large the openings between rooms can be? (See attatched diagram) Occupancy Classification

Code Reference: Section 302.1.1 defines an A-3 Occupancy as: "A building or portion of a building having an assembly room (emphasis added) with an occupant load of less than 300 without a legitimate stage, including such spaces used for educational purposes and not classified as Group B or E Occupancies."

Section 304.1 defines B Occupancies as: "Group B Occupancies shall include buildings, structures, or portions thereof, for office, professional or service type transactions, …, and eating and drinking establishments (emphasis added) with an occupant load of less than 50."

Table 10-A item 4 lists dining rooms and drinking establishments as less concentrated assembly areas using an occupant load factor of one person per 15 square feet and requires two exits when the occupant load is at least 50 persons.

A:  

Given the information submitted to the forum, the majority of the group felt the appropriate occupancy group is A-3, based on occupants' ability to migrate from space to space. It is important to note, however, that Section 301 assigns responsibility to the Building Official to classify a space or group of spaces, when the use isn't clear. The code panel members agreed that more information was needed to properly consider this question. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   In the Tri-County Checklist Section 5.0, items 5.20, 6.20, and 7.20 require structural calculations for vertical loads for equipment weighing more than400 pounds. Wouldn't any load beyond what was factored into the original design on the manufactured roof require an engineered design? If not, who would be liable for the added loading? If it is determined that all loads on manufactured roofs require engineered designs, shouldn't the Tri-County Checklist be revised so that applicants don't have to find out at the permit counter that they need an engineer for a 200-pound roof-top unit?
A:  

See OSSC, Volume 2, Section 1632.1. The 400 pound designation identified in this section refers only to seismic bracing. The structure must be capable of supporting the imposed gravity loads, and it may be necessary to provide a design proving that The code panel sent a revision request to the Tri-county Processes and Forms Committee (?) for review and action. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For plans with engineered lateral-load-resisting elements, how should we apply the use of "drag struts" or "collectors" to load-resisting elements such as shear walls or frames?
A:  

Plans with non-prescriptive (engineered) lateral-load-resisting elements must show sufficient load-transfer mechanism detail to provide a continuous load path. This may include drag struts, collectors, and blocking and strapping at re-entrant corners. (Tri-County Commercial Structural Building Code Forum, March 21, 2002


Q:   Section 1003.3.3.6 states: "Handrails shall be continuous the full length of the stairs..." Does that mean if there are landings within the flight of stairs that the handrail(s) shall be required to continue through the length of the landings?
A:  

No. Section 1003.3.3.1 stipulates that stairway includes stairs, landings, handrails and guardrails. All of these four components constitute a stairway. Section 1003.3.3.6 requires the handrails to be continuous for the full length of the stairs, not the stairway. With each intervening landing, you start new stairs. The handrail must still terminate properly and meet the other requirements of Section 1003.3.3.6. (Tri-County Building Code Forum, December 17, 2001)


Q:  

Can an exterior deck or balcony that is only accessed through an individual dwelling or guest unit in an Group R Division 1 Occupancy be considered as "within individual dwelling units" and therefore require only a 36 inch high guardrail?

 

Background: This question regards exterior deck or balcony guardrails for individual R-1 Occupancies. Section 509.2 of the OSSC states: "The top of guardrails shall not be less than 42 inches (1067 mm) in height. However, exception # 1 states: The top of guardrails for Group R, Division 3 and Group U, Division 1 Occupancies, and interior guardrails within individual dwelling units, Group R Division 3 congregate residences and guest rooms of Group R, Division 1 Occupancies may be 36 inches.

A:  

No. The code section referenced answers the question. The guardrail is not within the dwelling unit. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a one-hour rated wood frame floor-ceiling or roof-ceiling assemblies some jurisdictions require fire taping of the second (exposed) layer of gyp board while others do not.

Background: This question assumes that the gypsum board will be concealed either by surface applied materials or a suspended non-rated ceiling. It also assumes that the joints between the layers of gypsum board are staggered.
A:  

The builder needs to install per the approved assembly as prescribed by the approving agency. There may be several assemblies that are approved which can and do differ in their specific requirements. Build it as prescribed. (September 6, 2001 Tri-County Building Code Forum)


Q:   Is it the intent of the OSSC section 904.2.9 to sprinkler new apartments / condominiums three or more stories in height, even if the first floor contains a parking garage (U-1) that has the properly installed occupancy separations?
A:  

Yes. In the code, the definition of an apartment house is any building or portion thereof that contains three or more dwelling units. For the purpose of this code, that includes residential condominiums. Note that this definition refers to buildings that contain dwelling units. It does not exclude portions of the building other than dwelling units. Therefore, mixed occupancy buildings that are three or more stories in height which meet the definition of apartment house must be provided with an automatic sprinkler system throughout the entire structure. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a multistory wood-frame building some jurisdictions require one layer of 5/8 type X gypsum wallboard on the bottom of TJI joists, while others require two layers.
Background: This question concerns one-hour rated floor ceiling assemblies using pre-manufactured wood I-Joists. The assumption is that other elements of the assembly are followed. It also pertains to the lighter wood I joists rather than the TJI 55 series which has a NER tested assembly that permits a single layer outright. One key to this issue is the exchange of RC-1 channels and furring channels in the various assemblies.
A:  

Gypsum wallboard details, like the fire stopping details, need to be reviewed and agreed upon in advance. They are determined by the criteria found in the Gypsum Association manual Fire Resistance Design Manual and other approved sources such as Underwriter's Labs etc. In Tri-County, such details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the product, and to have it reviewed and approved, nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:  

Some jurisdictions allow fire-stopping methodology to be resolved in the field with a pre-installation meeting involving the affected parties. Other jurisdictions require fire-stopping details to be shown on the construction documents.


Background: The question here is not whether fire-stopping is required or not. Nor is it one that the general parameters for fire-stopping should not be laid out in the construction documents. Some jurisdictions however recognize that specifications and details may not reflect actual job conditions nor will they necessarily be drawn around the particular supplier of the fire-stop material.

A:  

Fire-stopping details need to be reviewed and agreed upon in advance, and must follow the manufacturer's instructions. In Tri-County, fire-stopping details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the appropriate product and to have it reviewed and approved nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do the sprinkler substitutions allowed in OSSC Section 508 allow the minimum one hour fire resistive protection mandates of OSSC 704.4 (requires members carrying masonry or concrete walls in buildings over one story in height to be a minimum of one hour fire-resistive construction or the fire-resistive requirements of the wall) to be waived as well?
A:  

No. 508 is a general requirement. 704.4 is a specific requirement and even applies to a non-rated building. Therefore you have to provide the one-hour protection or the fire-resistive requirement of the wall, whichever is greater. (Tri-County Building Code Forum, December 17, 2001)


Q:   For multifamily Type V - 1-HR building, do the interior closet walls need to be 1-hr construction? How about bathroom doors, closet doors, cabinets, etc.?
A:  

No. As long as you comply with Section 601.5.2.2 Hotels & Apartments, which states: "Interior nonbearing partitions within individual dwelling units in apartment houses and guestrooms or suites in hotels when such dwelling units guest rooms or suites are separated from each other and from corridors by not less than one-hour-fire-resistive construction may be constructed of: (2) Combustible framing with noncombustible materials applied to the framing in buildings of Type III or V construction.

As for bathroom doors, closet doors, cabinets etc. Section 601.5.5 Trim, states: "…Unprotected wood doors and windows may be used except where openings are required to be fire protected." (Tri-County Building Code Forum, December 17, 2001)


Q:   There are inconsistent code requirements for ventilation fans in row house construction. Every jurisdiction requires an under house fan, but some jurisdictions have required a squirrel fan, and some only require a normal bath fan. There should be a consistent requirement for the type and style of fan. Referred from the October 4, 2001 One and Two Family Code Forum.
A:  

Any fan applicable to the conditions will work-as long it meets the building code CFM rating. (Tri-County Building Code Forum, December 17, 2001)


Q:   Sometimes there are multiple permits for one job. When one permit is phoned in for an inspection, the inspectors take out all the permits and perform inspections on permits for which no inspection was requested in addition to the one which was requested. Staff is concerned that the other permits will not be inspected and that the contractor will cover the work. Is this appropriate? Should not all permits be phoned in separately for inspection?
A:  

No, it is not appropriate for inspectors to perform inspections on permits for which no inspection was requested. Yes, all permits should be phoned in separately for inspection; it is not up to the inspector to determine when the work is done; this is the responsibility of the contractor. When a contractor covers work that should be inspected it is a compliance issue that should be dealt with separately. (June 19 Tri-County Electrical Code Forum)


Q:   When is standby power required for egress illumination?
A:  

See 1003.2.9.2, "Power supply." (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   If the intent of the code is to provide the most direct egress for occupants, when is an enclosed vertical exit beneficial?
A:  

When such access serves three or more floors. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:  

Are these requirements applicable to an exterior door opening into a breezeway as described below:

 

Description - A three-story R-1 occupancy with stairways that provide egress from individual dwelling units to the public way or yard. The stairway is approximately 8 feet wide and 60 feet long with both ends fully open to the yard. The stairway is classified as interior because it does not meet UBC 1006.3.3.1 requirements for an exterior stairway.

UBC 1005.3.3, Exit Enclosures, requires interior stairways to be enclosed according to UBC 1005.3.3.3. The exterior openings may be unprotected where permitted by Table 5-A. In this case, unprotected exterior openings area allowed by Table 5-A and then only the walls separating the dwelling units from the exit are required to be fire rated.

UBC 1005.3.3.5, Openings and Penetrations, requires that the doors meet temperature-rise limitations: "All interior exit doors in an exit enclosure shall be protected by a fire assembly having a fire-protection rating of not less than one hour where one-hour-enclosure construction is permitted in Section 1005.3.3.2 and one and one-half hours where two-hour-enclosure construction is required by Section 1005.3.3.2. Such doors shall be maintained self-closing or shall be automatic closing by actuation of a smoke detector as specified in Section 713.2. All hold-open devices shall be listed for the intended purpose and shall close or release the fire assembly to the closed position in the event of a power failure. The maximum transmitted temperature end point for such doors shall not exceed 450? F (232?C) above ambient at the end of 30 minutes of the fire exposure specified in UBC Standard 7-2.

A:  

The temperature - rise limitation is required only for doors in an exit enclosure - not doors in a corridor. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Some jurisdictions waive the drinking fountain requirement in certain occupancies while others don't.

Background: This issue is primarily limited to occupancies in conjunction with R-1 occupancies. Another contributing factor is the availability of alternate sources of liquid. These alternate sources could be beverage bar, as our office has found in senior facilities or motels with continental breakfast.
A:  

A drinking fountain is required to be provided in an "A" and "E" occupancy on each floor level at an approved location (OSSC 2903.2). The only exception is "IN" a drinking or dining establishment. If there exists a conference area with a lobby/foyer, a drinking fountain shall be installed to serve the conference area. A drinking fountain is not required in the drinking or dining establishment portion of the "A" occupancy. Portable facilities or temporary facilities, such as water coolers or bottled water dispensers are not acceptable as alternatives as they can be easily removed or discontinued. Continental breakfast bars and juice bars, which may or may not be open to the public all day, do not qualify as eating or drinking establishments; thus they do not eliminate the requirement for a drinking fountain. (September 6, 2001 Tri-County Building Code Forum)


Q:   A corridor is part of an exit system, and is fully enclosed by walls, floor, ceiling, and protected openings according to UBC 1004.3.4.3. What is the difference between UBC 1004.3.4, Corridors, and 1005.3.3, Exit Enclosures?
A:  

A corridor is a portion of the exit access that leads occupants of a building to an exit. Though the term "corridor" is not defined in the code, it may be helpful to think of a corridor as being similar to a hallway: it provides access to various portions of a building and also provides access to the exterior. In multi-story buildings, corridors typically lead occupants to a stairway that leads to the ground floor. When this stairway serves three or more floors, Section 1005.3.3 requires the stairway to be located in a fire-rated enclosure called an "exit enclosure". The fire rating for the enclosure varies, depending on the type of construction and other factors. All openings leading into the exit enclosure must be fire-rated as well. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   UBC 1004.3.4. Corridors: Under what conditions does a corridor as defined in UBC 1004.3.4 become an exit enclosure as defined in UBC 1005.3.3? JSS: why does the question start with a ref to 1004.3.4, but that is not what the question refers to? Typo.
A:  

Corridors and exit enclosures are independent systems. A corridor becomes an exit enclosure when the corridor leads into or ends at a stair tower required to be an exit enclosure. UBC 1005.3.3. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Please provide the definition of attic space as it pertains to a panelized roof structure and insulation/holder assembly.
A:  

This question was referred to the State Building Codes Division for interpretation. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Are the UBC 1005.3.3.5 requirements for temperature-rise-limited doors applicable to an exterior door that exits into a corridor open to the exterior at both ends? For example, a door on an exterior wall but within a breezeway..
A:  

No, not when the door exits into a corridor; however, the requirements apply when the door exits into a stair enclosure. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   If an exit meets the requirements of a corridor as defined in UBC 1004.3.4, does it also need to meet the requirements of an exit enclosure as defined in UBC 1005.3.3.5?
A:  

No, the two satisfy different requirements. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Can a corridor include stairs that are otherwise not required to be enclosed?
A:  

Yes. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Fire Dampers in non-rated ceilings. We are installing new furnaces and new ductwork into a church where none of the ceilings are fire rated. They should be fire rated but the church is over 50 years old. In most jurisdictions, because the ceiling is not rated, we would not have to put fire dampers in the registers that penetrate the ceiling because it would not add any protection-a fire would just burn around the dampers. One jurisdiction is requiring us to put in fire dampers, reasoning that the ceiling should be fire rated and so we have to put them in based on what it should be. This does not seem consistent with other jurisdictions. We also recently did a job in a jurisdiction in which we did not need to install fire dampers or even smoke/fire dampers in the hallways because the building already had a sprinkler system. Yet a half-mile away-in another jurisdiction, the Fire Marshall-in an inspection of a church, required that the church add fire dampers (not smoke/fire dampers) to all of the hallway ceiling registers. What is right? Referred from the August 9, 2001 Mechanical Code Forum.
A:  

When a fire-rated construction is penetrated, fire dampers are required. If the construction is not fire rated (as per 713.11 & 711.4) fire dampers are not necessary. In cases like these where the ceilings were not rated, smoke/fire dampers should not have been required. In these cases, the Plans Examiner required fire dampers because the existing 50-year-old ceiling should be fire-rated by today's standards. It is important to note that we cannot base code requirements on our wishes or what we feel "should be." (September 6, 2001 Tri-County Building Code Forum)


Q:   Our department would classify a 14,000-square-foot building that houses a city or county library A-3, however, some architects say that such buildings in the tri-county area have been classified B with some accessory A uses. What is the correct classification?
A:  

Typically, libraries are "B" occupancies. But many contemporary libraries are designed for multiple uses beyond the traditional book lending and study areas to community meeting rooms and even city council chambers. In such cases, other occupancies may apply. The code panel strongly recommends that design professionals contact the building-department jurisdiction during the conceptual phase. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Recently, there has been some discussion regarding the classification of a Library. Given 14,000 s.f. Library (City or County) I would classify this building as an A-3. However, some architect's claim that such buildings in the Portland area have been classified as a B with some accessory A uses. Could you add this as a question at the building code forum?
A:  

A-3 or A-2.1 based on occupancy. You look at the predominate use of the building for assigning a use group to the building. For incidental uses of the building, their percentage of the whole area need to be determined. If the accessory /incidental use is less than 25 percent then the predominant use of the building is the main use. When you have an area where people are assembling, which in the case of a library is true, you have to classify it under Assembly use group. (Tri-County Building Code Forum, December 17, 2001)

 

The following Q and A is a reconsideration of a previous code forum answer on the subject


Q:   Should a building department accept drawings prepared by an engineer or architect but not stamped by them? In other words, is an engineer or architect required to stamp final documents when the building is exempt from the Architect's Law? How many sets of documents must carry a "wet signature"?
A:  

OAR 806-010-0045. No. An Oregon registered architect is required to stamp and sign all his or her work in this state regardless of its exemption status. Only one set of submittal documents must bear the wet signature of the architect or engineer. It is permissible for the professional stamp or seal to be electronically duplicated. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   Are the parking provisions of OSSC 1104 retroactive?
A:  

No. You must still comply with Federal ADA requirements. These requirements were retroactive in OSSC till October 1, 1996 as can be seen from the language in Section 3101(e) of the 1993 OSSC which, states "Except as required in Section 3104 for accessible parking, this code is not retroactive…". When the 1996 OSSC was adopted effective October 1, 1996, the retroactive code requirement for accessible parking were dropped from the OSSC. (Tri-County Building Code Forum, December 17, 2001)


Q:   How does Chapter 13 relate to a new packaged A/C installation on an existing building?  Specifically, is the minimum EER rating 12.5 or 10.9? The footnotes to Table 13-N on page 140.36 of the 4/1/04 version of Chapter13 refer to "New Construction" and "replacements."  It is not clear which category would apply in our case.  This is not a replacement but a new system, including all new ducts, to be installed in an existing building. This unit will provide additional cooling and ventilation for an existing tenant space and serve a newly created tenant space within an existing building.
A:   Use the calculation for new construction. (Tri-County Code Forum, December 2004)
Q:   The IBC, 502.1 defines Building Area as "The area included within surrounding exterior walls..." In calculating the allowable area, is the area of the exterior walls to be included, or just the interior area exclusive of the exterior walls?
A:  

For the purposes of calculating the allowable area in OSSC section 503, the IBC Commentary says that the allowable area is the inside face of the exterior wall. However, the panel refers this question to the state for interpretation: www.bcd.oregon.gov/programs/structural/interps/OSSC_Interp_503_area_of_building.pdf 
(Tri-County Code Forum June 2005)


Q:   Will the text given in 302.2.1, which states that assembly spaces that are accessory uses to Group E are not required to be considered separate occupancies be interpreted in Tri-County to mean that there is no occupancy separation required?  Table 302.3.2 indicates separation is required (2-Hour) which seems to be in conflict with 302.2.1. The spaces we are curious about typically include gymnasiums, school cafeteria, and possibly school library.
A:   The code section refers to assembly occupancies that are accessory to Group E, in which case they are not required to be separated. If, by chance, there was an A occupancy adjacent to the E, but under separate control, then they would need the appropriate occupancy separation. (Tri-County Code Forum, September 2004)
Q:   Paragraph 303.1 states that assembly spaces which are accessory to Group E in accordance with 302.2 are not considered assembly occupancies. Will that be the case for K-12 public school buildings in Tri-County? If yes, are these uses classified as E for the purposes of determining occupant load, egress width, etc.?
A:   Section 302.3.1 states that for non-separated uses, all other code requirements shall apply to each portion of the building based on the use of that space. The exiting requirements for the assembly portions of the building need to meet the requirements based on that use. (Tri-County Code Forum, September 2004)
Q:   Please clarify the definition of atrium per 404.1.1 as it relates to an opening in a two-story building.
A:  

The definition in the 2004 OSSC of what constitutes an "atrium" is nearly identical to that found in section 202 of the 1998 OSSC. However, the  companion provisions for "shafts" and "vertical exit enclosures" in the respective code editions have changed considerably.

 

For example, section 711.3 of the 1998 OSSC stated that; "In other than Group I Occupancies, openings that penetrate only one floor and are not connected with openings communicating with other stories or basements and that are not concealed within building construction assemblies need not be enclosed." As such, most required stairways were permitted to atmospherically connect two floors.

 

In contrast, section 707.2, exception 7.2 of the 2004 OSSC will not allow the "required means of egress system" to be unenclosed  between floors except as permitted in section 1019.1. A cursory look at section 1019.1 reveals that the required stairways in the means of egress must be enclosed except for the following circumstances:

 

In other than Group H and I occupancies, a stairway serving an occupant load of less than 10 not more than one story above the level of exit discharge.

In other than occupancy Groups H and I, a maximum of 50 percent of egress stairways serving one adjacent floor are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Any two such interconnected floors shall not be open to other floors.

 

In other than occupancy Groups H and I, interior egress stairways serving only the first and second stories of a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Such interconnected stories shall not be open to other stories.

 

In short, where a sprinkler system is installed, stairways serving the first and second stories may be unenclosed. In unsprinklered buildings, 50 percent of the egress stairways and stairways serving 10 or less persons above the level of exit discharge may be unenclosed.

 

As noted, this is only one example of the differences. Sections 404, 707.2 and 1019.1 contain additional exceptions that warrant further examination and application. (Tri-County Code Forum, March 2005)
Q:   For purposes of applying the requirements for natural light, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural light from the living/dining area?
A:   Yes, if it meets the qualifications of the opening described in Section 1205.2.1. of the 2004 0SSC. (Tri-County Code Forum, September 2004)
Q:   Assuming the "den" is not provided with mechanical ventilation, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural ventilation from the living/dining area?
A:   Yes, if the opening meets the minimum opening requirements of Section 1203.4.1.1 of the 2004 OSSC . (Tri-County Code Forum, September 2004)
Q:  

1-4. Code References: 

Section 310.4  Basements in dwelling units and every sleeping room below the fourth story shall have at least one operable window or door approved for emergency escape or rescue that shall open directly to a public street, public alley, yard or exit court.

 

Section 1204.2  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural light by means of exterior glazed openings with an area not less than one tenth the floor area of such rooms with a minimum of 10 square feet.


Section 1204.3  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural ventillation as specified in section 1203.2.4 or by a mechanical ventilation system which shall be capable of supplying ventilation air in accordance with Table 12-A.

 

Section 1204.1  For the purpose of determining the light or ventilation and source control ventilation for Group R Occupancies required by this section and Table 12-A, any room may be considered as a portion of an adjoining room when one half of the area of the common wall is open and unobstructed and provides an opening of not less that one tenth of the floor area of the interior room or 25 square feet, whichever is greater.

 

The floor plans for dwelling units each have an interior room labeled as a "den." In one unit the "den" has a clothes closet. The "den" in the other unit does not have a closet. Assuming these units are not in a building complying with the requirements of chapter 4 for a high rise building, please respond to the following questions:

 

Is the "den" containing the clothes closet considered a sleeping room for purposes of applying emergency egress requirements?  Is the "den" that does not contain a closet considered a sleeping room for purposes of applying emergency egress requirements?

A:   The applicant is required to label the rooms accurately. If the room has a closet and is labeled "den," building departments should accept the designation and make no assumption that it will be used other than how it is labeled. For example, many living rooms have closets but are not treated as sleeping rooms. (Tri-County Code Forum, September 2004)
Q:   We have a clarification request for the next Building Code Forum.  One of our colleagues recently found the following: Under section 105.2 Exceptions 13 (Agricultural Structures) and 14 ( Equine Facilities), the new code refers to ORS 455.310. ORS 455.310 covers exempt residential construction, not agricultural structures. ORS 455.315 covers exempt agricultural structures. See ORS index at http://www.leg.state.or.us/ors/455.html You may want to point this out so that it is addressed in future issuances of the Code.
A:   The wrong statute was cited in the code and will be corrected. (Tri-County Code Forum, March 2005)
Q:   What are the new OSSC requirements for firewalls in apartments?
A:   The new code requires the dwelling unit separation to be one hour, unless the building is sprinkled; then unit separation can be 30 minutes. See also section 708. (Tri-County Code Forum, June 2005)
Q:   Is there a definition for a 30-minute wall?
A:   Table 721.6.2 of the OSSC  assigns a fire-resistive time period to various wall components. Using this table, a designer is able to establish an overall fire-resistive time period for a given assembly by adding up the times assigned to interior and exterior membranes, the wood frame and the addition of certain insulations (unique to wood frame construction). (Tri-County Code Forum, June 2005)
Q:   If the 2-1/2 inch net section is still required by the 2004 Structural Specialty Code, does the minimum net section apply to metal plate connected pre-engineered roof trusses used to anchor masonry or concrete walls?
A:   The prescriptive provisions have been replaced with design provisions. (Tri-County Code Forum, June 2005)
Q:   For ADA access, the code requires 12 inches adjacent to the ?push? side of a door equipped with a closer and a latch. If the latch is panic hardware, is the 12 inches of adjacent space still required?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   When there are several properties under the same ownership how do you treat property lines?
A:   Contact your local jurisdiction. The answer depends on which jurisdiction you?re in and must be judged on a case by case basis. Suggestions from the panel included the use of a covenant (not to sell separately) or a lot line adjustment. (Tri-County Code Forum, September 2004)
Q:  

Are there situations in which an accessible table located adjacent to a bar counter can be provided instead of a 60-inch long portion of the bar counter lowered to 34 inches?

Bar counters in restaurants and lounges are usually 36 to 44 inches high where patrons sit on raised seats. Ice and drink dispensers, coolers, sinks, and other equipment are typically built into the barkeep side of the casework. It is common for small restaurants to propose a 6 to 8 foot long bar.

 

Section 1108.4.5 completely eliminates raised bar counters that are 5 feet long or less. Bar counters less than 10 feet long are impractical because the remaining raised portion is less than 5 feet long. The end result is the restaurant does not have a raised bar, which seems overly restrictive.

 

Note that The Americans with Disabilities Act Accessibility Guidelines (ADAAG) Section 5.2 allows bar service to be provided at accessible tables within the same area as the raised counter.

A:  

Section 1101.6 references ORS 447.250 and allows waivers or modifications if the code section is more restrictive than ADA guidelines or the Fair Housing Act. If the new ADAAG guidelines allow this alternate method, the applicant may be able to appeal to the state. It could also be approved at the local level as an alternate method, but jurisdictions may be hesitant to make this approval without guidance from the state.

 

It would seem that if a table is assigned for use as an "accessible table" and is made available for use when needed that it could fulfill the requirement. However, if the table was in use and was then needed, it could create a slight inconvenience as the current patrons would have to be relocated to make room for the physically challenged user. (Tri-County Code Forum, September 2004)


Q:   Our current project is the restoration of a fire-damaged school. Would this work be considered a "repair," an "addition," or an "alteration"? While most of the project consists of rebuilding the classrooms and does not include adding any new space, the original structure is more than 65 years old and could use some structural updates, as well as the addition of an smoke alarm system. Would such additions change the category of construction?
A:   The work to restore the fire-damaged area would be considered a repair, even if new trusses must be added to be sufficient to carry the load. The fire code  has a retroactive provision that requires smoke alarms in all such buildings. Work with your local building official to discuss details. (Tri-County Code Forum, June 2005)
Q:   Do S2 parking structures need to be sprinklered?
A:   406.4 and 903.2.9 Open, no; enclosed, yes. (Tri-County Code Forum, June 2005)
Q:   Does the shape of the ceiling tiles, whether they are flat or regular, have a  bearing on the grid requirements?
A:   No. (Tri-County Code Forum, June 2005)
Q:   Can tiles be scribed in at all sides and not affect the deflection of the grid?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   If a ceiling grid system has no tiles or lights directly attached to the grid, does it then become an aesthetic system and not need to meet any of the ceiling grid code requirements?
A:   Any such grid system must meet the structural code requirements. (Tri-County Code Forum, June 2005)
Q:   Please clarify 1621 and referenced ASCE 9.6.2.6.2.2 as it relates to suspended ceiling tile and sprinkler head design.
A:   The panel refers this question to the Building Codes Division for interpretation. It appears that it is extremely difficult for builders to locate sprinklers or seismic joints that are the correct size. (Tri-County Code Forum, March 2005)
Q:   What is the requirement for upper cabinet height?
A:  

UFAS (Kitchen storage) states that " Max. height shall be 48inches for at least one shelf of all cabinets & storage shelves mounted above work counters.? Does that mean one shelf of EACH upper cabinet? Or does that mean just one shelf is required to be mounted at 48 inches and the others can be mounted higher?


UFAS is not the adopted accessibility standard in the State of Oregon. However,  OSSC 1109.11.2, which is based on the Americans with Disabilities Act Architectural Guidelines (ADAAG), requires 50 percent of the cabinets to have at least one shelf within the height limitation. (Tri-County Code Forum, June 2005)


Q:   I have a question for further clarification on a ventilation question related to the Q&A posed during the April 8 forum and answered in the August-October 2004 News Site, specifically Oregon Structural Specialty Code, Section 1505. Can alternate ventilation (gable end vents or extra vents in non-vaulted areas) be installed to compensate for any blocked or restricted soffit vents, due to insulation filled rafter or scissor truss cavities, and achieve a 150:1 venting requirement? Any 2x6, 2x8, 2x10 rafter, for a vaulted ceiling, is simply too small to allow for R-30 Fiberglass Batt insulation and allow 1" air gap. (R-30= 9-1/4(one quarter)" for high density fiberglass insulation, 2x10 =9-1/4(one quarter)"   there is no room for air gap) Any scissor truss is only 3-1/2(one half)" at the soffit vent, and there is no possible way to achieve either R-30 or the required air gap for the first 18" to 36" of the scissor truss cavity (depending upon pitches) There is a conflict between structural codes allowing 2x4 trusses, 2x6, 2x8 and 2x10 rafters, the insulation requirements and ventilation requirements. The insulation gets crammed into rafter spaces and venting is blocked off. When scissor trusses or less than 2x12 rafters are used, the plans examiner should be able to know that mathematically the soffit vents will be blocked. Shouldn't this be the step when alternate venting should be called out? How do we meet all three requirements? We have had call-back on houses that "meet codes" and were signed off, but now have high moisture build-up in the attic and mold growth on the roof sheeting. Obviously the current venting is not working!
A:   The code allows for the compression of roof insulation in sloped roof assemblies in proximity to eave vents. The code also requires the installation of "baffles" in order to maintain cross ventilation. (Tri-County Code Forum, December 2004)
Q:   Please clarify the definition of "walls directly attached to structure."  Do walls that are braced to the structure meet his requirement?
A:   If the wall is bracing a building, or it is relying on the building for its support, it is a part of the structure. (Tri-County Code Forum, June 2005)
Q:   What if you re-stripe?
A:  

If you're repainting the existing stripes in an existing lot over the existing stripes, that is fine, the repainting of the stripe can be to match existing stripes. If you want to move spaces or change the configuration, you can do so as long as you comply with the code in existence at the time of reconfiguring the parking lot. (Tri-County Building Code Forum, December 17, 2001)


Q:   The 1998 Structural Specialty Code based on the 1997 UBC Section 1633.2.8.1. Item 5 requires that wood elements of a concrete or masonry wall anchorage system "have a minimum actual net thickness of 2 1/2 inches."  Does the current 2004 Structural Specialty Code based on the 2003 IBC have an equivalent requirement?  If yes, where is the citation requiring 2-1/2 inch (3x)wood elements for the anchorage of concrete or masonry wall systems?
A:   No. There is nothing in the current code that addresses this issue. (Tri-County Code Forum, June 2005)

Fire, Life-Safety

Q:   There is widespread inconsistency in accessibility requirements. Some jurisdictions have issued accessibility interpretations while others don't even review accessibility details in the documents saying that this is a federal civil law.
A:  

The Building Official, by ORS 447, is responsible to enforce these provisions (Chapter 11) of the code. Therefore all jurisdictions should provide accessibility guidelines for plan review and provide comments to the applicant during the plan review process. Beginning Sept. 1, Tri-County jurisdictions are required to use the commercial application checklist and process. This process provides the opportunity for a pre-submittal meeting during which the jurisdiction can outline the accessibility requirements of the project, using the commercial application checklist as a guide.(September 6, 2001 Tri-County Building Code Forum)


Q:   Is it permissible to compare only base shear values for wind and earthquake loads to decide whether wind or seismic loads govern the design?
A:  

No, it is not permissible. A correct analysis requires determining both the earthquake loads and the wind loads on an element of a structure. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For an existing building being relocated with no interior remodel or change of use, what are the upgrade requirements by code?
A:  

Section 3404 of the OSSC addresses "moved buildings" as does ORS 455.410 entitled "Relocated Buildings; Substantial Compliance Required; Permits." The statute states that "existing buildings or structures which are removed from their foundation and relocated to another site within this state shall be in substantial compliance in accordance to the statute." In short, the statute recognizes moved buildings as existing structures. This statute defines "substantial compliance" and addresses upgrade requirements in terms of foundation construction, installation upgrades, smoke detection and permit requirements. The statute requires the new foundation to fully comply with current building codes. It also requires the ceiling and underfloor insulation to be upgraded to current levels. It requires the installation of smoke alarms at all locations the code imposes for new construction, but only requires the alarms to be hardwired and interconnected when wall and ceiling finishes have been removed, much like we see with residential alterations. The jurisdiction cannot require existing windows (or other elements) to be upgraded for reasons of energy code compliance or to meet egress requirements. The only time a jurisdiction can require upgrades is in the case where the moved structure is altered and then only those portions that are altered must be upgraded. For example, let's say an existing 3-bedroom dwelling is relocated to a new site. The plans show that the kitchen will be remodeled as will the master bedroom. The master bedroom shows a new window being installed but the other 2 bedrooms show no alterations. The Plans Examiner knows that the windows in the other 2 bedrooms have a sill height of greater than 44" above the finish floor and thus do not meet current code. Can the examiner require the master bedroom window to meet egress? Yes, because is it is "new" and not a part of the "existing" dwelling. Can the examiner require the windows in the other two bedrooms to be replaced? No, because they are existing.

(September 6, 2001 Tri-County Building Code Forum)


Q:  

There are some jurisdictions in the Tri-County area that accept single user, unisex toilettes in "A" occupancy while others don't.


Background: When this issue is not resolved until building permit application time, it is very difficult to resolve in a building that has been fully designed.

A:  

Section 101.3 (Scope) incorrectly identifies Appendix Chapter 29 as being adopted. When the code was last modified, provisions of the appendix chapter were brought forward to the regular chapter eliminating the need for the appendix chapter. However, Table 29-A is adopted by reference in Section 2902.2. To be clear, only Table 29-A is adopted. That said, occupancies are required to have restrooms in the number determined by Chapter 29 and Table 29-A. Section 1108.2.2 imposes an additional requirement that an accessible, unisex toilet facility be provided where an aggregate of six or more male and female water closets are required in "A" occupancies, recognizing that in larger facilities it is likely that a disabled person might require assistance by a member of the opposite sex. In "M" occupancies, the required number of toilets may be much lower; in fact, a single-occupant unisex accessible restroom might fulfill all code requirements. Finally, in existing facilities, where it is impractical to fully comply with the code, Section 1113.3.7.1 may be invoked. This section allows one unisex facility in lieu of making existing facilities accessible. See 2904.2, which deals with the substantial alteration of existing Group A occupancies. The building official may approve substantial alterations without the installation of additional water closets only where it is structurally unfeasible to make such alterations. (September 6, 2001 Tri-County Building Code Forum)


Q:  

In a multistory rated building some jurisdictions require a "lid" on the bottom side of a private balcony while others do not.


Background: This typically occurs in a Type-V One-Hour, R-1 occupancy and multistory buildings where there are unit balconies that stack. It is generally agreed that even when using pressure treated materials, enclosing these decks on the underside will rapidly lead to deterioration in our moist climate. Venting these areas on the horizontal surface is not permitted in the code. Face vents are problematic. This issue regards conventional construction and not the use of heavy timber. It also deals specifically with private balconies, not exterior exit balconies.

A:  

Section 705 (Projections) speaks to architectural appendages beyond the floor area and thus applies to exterior balconies. Projections from Type-V construction may be of combustible or noncombustible construction. These projections are only required to be protected with one-hour fire resistive construction where openings are required to be protected or where they are prohibited. Therefore, balconies (other than exterior exit balconies) can be of unprotected construction. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do older buildings require seismic upgrading?
A:  

Portland has an ordinance requiring the seismic upgrading of un-reinforced masonry buildings that the City has specifically listed. Nothing in the code mandates such upgrades, but the code does give guidance about providing the upgrades. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Can a uniform commercial re-roofing permit and procedure be developed for tri-county area?
A:  

Mr. Watts with Associated Roofing Contractors posed this question. He represents commercial roofing companies in the tri-county region. The roofing association would like consistency and a uniform approach to handling re-roofing projects in the tri-county area. Mr. Watts mentioned some jurisdictions require engineering reports and some do not and noted that consistency also varies among jurisdictions regarding pre-inspections.

The panel forwarded this issue to the Tri-County Processes and Forms committee for discussion and action. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   What occupancy classification should be assigned to a dining/drinking establishment that contains more than one room each with an occupant load of 49 or less but with a total combined occupant load exceeding 50 and with room having one code compliant exit? Are there any restrictions on how large the openings between rooms can be? (See attatched diagram) Occupancy Classification

Code Reference: Section 302.1.1 defines an A-3 Occupancy as: "A building or portion of a building having an assembly room (emphasis added) with an occupant load of less than 300 without a legitimate stage, including such spaces used for educational purposes and not classified as Group B or E Occupancies."

Section 304.1 defines B Occupancies as: "Group B Occupancies shall include buildings, structures, or portions thereof, for office, professional or service type transactions, …, and eating and drinking establishments (emphasis added) with an occupant load of less than 50."

Table 10-A item 4 lists dining rooms and drinking establishments as less concentrated assembly areas using an occupant load factor of one person per 15 square feet and requires two exits when the occupant load is at least 50 persons.

A:  

Given the information submitted to the forum, the majority of the group felt the appropriate occupancy group is A-3, based on occupants' ability to migrate from space to space. It is important to note, however, that Section 301 assigns responsibility to the Building Official to classify a space or group of spaces, when the use isn't clear. The code panel members agreed that more information was needed to properly consider this question. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   In the Tri-County Checklist Section 5.0, items 5.20, 6.20, and 7.20 require structural calculations for vertical loads for equipment weighing more than400 pounds. Wouldn't any load beyond what was factored into the original design on the manufactured roof require an engineered design? If not, who would be liable for the added loading? If it is determined that all loads on manufactured roofs require engineered designs, shouldn't the Tri-County Checklist be revised so that applicants don't have to find out at the permit counter that they need an engineer for a 200-pound roof-top unit?
A:  

See OSSC, Volume 2, Section 1632.1. The 400 pound designation identified in this section refers only to seismic bracing. The structure must be capable of supporting the imposed gravity loads, and it may be necessary to provide a design proving that The code panel sent a revision request to the Tri-county Processes and Forms Committee (?) for review and action. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For plans with engineered lateral-load-resisting elements, how should we apply the use of "drag struts" or "collectors" to load-resisting elements such as shear walls or frames?
A:  

Plans with non-prescriptive (engineered) lateral-load-resisting elements must show sufficient load-transfer mechanism detail to provide a continuous load path. This may include drag struts, collectors, and blocking and strapping at re-entrant corners. (Tri-County Commercial Structural Building Code Forum, March 21, 2002


Q:   Section 1003.3.3.6 states: "Handrails shall be continuous the full length of the stairs..." Does that mean if there are landings within the flight of stairs that the handrail(s) shall be required to continue through the length of the landings?
A:  

No. Section 1003.3.3.1 stipulates that stairway includes stairs, landings, handrails and guardrails. All of these four components constitute a stairway. Section 1003.3.3.6 requires the handrails to be continuous for the full length of the stairs, not the stairway. With each intervening landing, you start new stairs. The handrail must still terminate properly and meet the other requirements of Section 1003.3.3.6. (Tri-County Building Code Forum, December 17, 2001)


Q:  

Can an exterior deck or balcony that is only accessed through an individual dwelling or guest unit in an Group R Division 1 Occupancy be considered as "within individual dwelling units" and therefore require only a 36 inch high guardrail?

 

Background: This question regards exterior deck or balcony guardrails for individual R-1 Occupancies. Section 509.2 of the OSSC states: "The top of guardrails shall not be less than 42 inches (1067 mm) in height. However, exception # 1 states: The top of guardrails for Group R, Division 3 and Group U, Division 1 Occupancies, and interior guardrails within individual dwelling units, Group R Division 3 congregate residences and guest rooms of Group R, Division 1 Occupancies may be 36 inches.

A:  

No. The code section referenced answers the question. The guardrail is not within the dwelling unit. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a one-hour rated wood frame floor-ceiling or roof-ceiling assemblies some jurisdictions require fire taping of the second (exposed) layer of gyp board while others do not.

Background: This question assumes that the gypsum board will be concealed either by surface applied materials or a suspended non-rated ceiling. It also assumes that the joints between the layers of gypsum board are staggered.
A:  

The builder needs to install per the approved assembly as prescribed by the approving agency. There may be several assemblies that are approved which can and do differ in their specific requirements. Build it as prescribed. (September 6, 2001 Tri-County Building Code Forum)


Q:   Is it the intent of the OSSC section 904.2.9 to sprinkler new apartments / condominiums three or more stories in height, even if the first floor contains a parking garage (U-1) that has the properly installed occupancy separations?
A:  

Yes. In the code, the definition of an apartment house is any building or portion thereof that contains three or more dwelling units. For the purpose of this code, that includes residential condominiums. Note that this definition refers to buildings that contain dwelling units. It does not exclude portions of the building other than dwelling units. Therefore, mixed occupancy buildings that are three or more stories in height which meet the definition of apartment house must be provided with an automatic sprinkler system throughout the entire structure. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a multistory wood-frame building some jurisdictions require one layer of 5/8 type X gypsum wallboard on the bottom of TJI joists, while others require two layers.
Background: This question concerns one-hour rated floor ceiling assemblies using pre-manufactured wood I-Joists. The assumption is that other elements of the assembly are followed. It also pertains to the lighter wood I joists rather than the TJI 55 series which has a NER tested assembly that permits a single layer outright. One key to this issue is the exchange of RC-1 channels and furring channels in the various assemblies.
A:  

Gypsum wallboard details, like the fire stopping details, need to be reviewed and agreed upon in advance. They are determined by the criteria found in the Gypsum Association manual Fire Resistance Design Manual and other approved sources such as Underwriter's Labs etc. In Tri-County, such details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the product, and to have it reviewed and approved, nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:  

Some jurisdictions allow fire-stopping methodology to be resolved in the field with a pre-installation meeting involving the affected parties. Other jurisdictions require fire-stopping details to be shown on the construction documents.


Background: The question here is not whether fire-stopping is required or not. Nor is it one that the general parameters for fire-stopping should not be laid out in the construction documents. Some jurisdictions however recognize that specifications and details may not reflect actual job conditions nor will they necessarily be drawn around the particular supplier of the fire-stop material.

A:  

Fire-stopping details need to be reviewed and agreed upon in advance, and must follow the manufacturer's instructions. In Tri-County, fire-stopping details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the appropriate product and to have it reviewed and approved nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do the sprinkler substitutions allowed in OSSC Section 508 allow the minimum one hour fire resistive protection mandates of OSSC 704.4 (requires members carrying masonry or concrete walls in buildings over one story in height to be a minimum of one hour fire-resistive construction or the fire-resistive requirements of the wall) to be waived as well?
A:  

No. 508 is a general requirement. 704.4 is a specific requirement and even applies to a non-rated building. Therefore you have to provide the one-hour protection or the fire-resistive requirement of the wall, whichever is greater. (Tri-County Building Code Forum, December 17, 2001)


Q:   For multifamily Type V - 1-HR building, do the interior closet walls need to be 1-hr construction? How about bathroom doors, closet doors, cabinets, etc.?
A:  

No. As long as you comply with Section 601.5.2.2 Hotels & Apartments, which states: "Interior nonbearing partitions within individual dwelling units in apartment houses and guestrooms or suites in hotels when such dwelling units guest rooms or suites are separated from each other and from corridors by not less than one-hour-fire-resistive construction may be constructed of: (2) Combustible framing with noncombustible materials applied to the framing in buildings of Type III or V construction.

As for bathroom doors, closet doors, cabinets etc. Section 601.5.5 Trim, states: "…Unprotected wood doors and windows may be used except where openings are required to be fire protected." (Tri-County Building Code Forum, December 17, 2001)


Q:   There are inconsistent code requirements for ventilation fans in row house construction. Every jurisdiction requires an under house fan, but some jurisdictions have required a squirrel fan, and some only require a normal bath fan. There should be a consistent requirement for the type and style of fan. Referred from the October 4, 2001 One and Two Family Code Forum.
A:  

Any fan applicable to the conditions will work-as long it meets the building code CFM rating. (Tri-County Building Code Forum, December 17, 2001)


Q:   Sometimes there are multiple permits for one job. When one permit is phoned in for an inspection, the inspectors take out all the permits and perform inspections on permits for which no inspection was requested in addition to the one which was requested. Staff is concerned that the other permits will not be inspected and that the contractor will cover the work. Is this appropriate? Should not all permits be phoned in separately for inspection?
A:  

No, it is not appropriate for inspectors to perform inspections on permits for which no inspection was requested. Yes, all permits should be phoned in separately for inspection; it is not up to the inspector to determine when the work is done; this is the responsibility of the contractor. When a contractor covers work that should be inspected it is a compliance issue that should be dealt with separately. (June 19 Tri-County Electrical Code Forum)


Q:   When is standby power required for egress illumination?
A:  

See 1003.2.9.2, "Power supply." (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   If the intent of the code is to provide the most direct egress for occupants, when is an enclosed vertical exit beneficial?
A:  

When such access serves three or more floors. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:  

Are these requirements applicable to an exterior door opening into a breezeway as described below:

 

Description - A three-story R-1 occupancy with stairways that provide egress from individual dwelling units to the public way or yard. The stairway is approximately 8 feet wide and 60 feet long with both ends fully open to the yard. The stairway is classified as interior because it does not meet UBC 1006.3.3.1 requirements for an exterior stairway.

UBC 1005.3.3, Exit Enclosures, requires interior stairways to be enclosed according to UBC 1005.3.3.3. The exterior openings may be unprotected where permitted by Table 5-A. In this case, unprotected exterior openings area allowed by Table 5-A and then only the walls separating the dwelling units from the exit are required to be fire rated.

UBC 1005.3.3.5, Openings and Penetrations, requires that the doors meet temperature-rise limitations: "All interior exit doors in an exit enclosure shall be protected by a fire assembly having a fire-protection rating of not less than one hour where one-hour-enclosure construction is permitted in Section 1005.3.3.2 and one and one-half hours where two-hour-enclosure construction is required by Section 1005.3.3.2. Such doors shall be maintained self-closing or shall be automatic closing by actuation of a smoke detector as specified in Section 713.2. All hold-open devices shall be listed for the intended purpose and shall close or release the fire assembly to the closed position in the event of a power failure. The maximum transmitted temperature end point for such doors shall not exceed 450? F (232?C) above ambient at the end of 30 minutes of the fire exposure specified in UBC Standard 7-2.

A:  

The temperature - rise limitation is required only for doors in an exit enclosure - not doors in a corridor. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Some jurisdictions waive the drinking fountain requirement in certain occupancies while others don't.

Background: This issue is primarily limited to occupancies in conjunction with R-1 occupancies. Another contributing factor is the availability of alternate sources of liquid. These alternate sources could be beverage bar, as our office has found in senior facilities or motels with continental breakfast.
A:  

A drinking fountain is required to be provided in an "A" and "E" occupancy on each floor level at an approved location (OSSC 2903.2). The only exception is "IN" a drinking or dining establishment. If there exists a conference area with a lobby/foyer, a drinking fountain shall be installed to serve the conference area. A drinking fountain is not required in the drinking or dining establishment portion of the "A" occupancy. Portable facilities or temporary facilities, such as water coolers or bottled water dispensers are not acceptable as alternatives as they can be easily removed or discontinued. Continental breakfast bars and juice bars, which may or may not be open to the public all day, do not qualify as eating or drinking establishments; thus they do not eliminate the requirement for a drinking fountain. (September 6, 2001 Tri-County Building Code Forum)


Q:   A corridor is part of an exit system, and is fully enclosed by walls, floor, ceiling, and protected openings according to UBC 1004.3.4.3. What is the difference between UBC 1004.3.4, Corridors, and 1005.3.3, Exit Enclosures?
A:  

A corridor is a portion of the exit access that leads occupants of a building to an exit. Though the term "corridor" is not defined in the code, it may be helpful to think of a corridor as being similar to a hallway: it provides access to various portions of a building and also provides access to the exterior. In multi-story buildings, corridors typically lead occupants to a stairway that leads to the ground floor. When this stairway serves three or more floors, Section 1005.3.3 requires the stairway to be located in a fire-rated enclosure called an "exit enclosure". The fire rating for the enclosure varies, depending on the type of construction and other factors. All openings leading into the exit enclosure must be fire-rated as well. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   UBC 1004.3.4. Corridors: Under what conditions does a corridor as defined in UBC 1004.3.4 become an exit enclosure as defined in UBC 1005.3.3? JSS: why does the question start with a ref to 1004.3.4, but that is not what the question refers to? Typo.
A:  

Corridors and exit enclosures are independent systems. A corridor becomes an exit enclosure when the corridor leads into or ends at a stair tower required to be an exit enclosure. UBC 1005.3.3. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Please provide the definition of attic space as it pertains to a panelized roof structure and insulation/holder assembly.
A:  

This question was referred to the State Building Codes Division for interpretation. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Are the UBC 1005.3.3.5 requirements for temperature-rise-limited doors applicable to an exterior door that exits into a corridor open to the exterior at both ends? For example, a door on an exterior wall but within a breezeway..
A:  

No, not when the door exits into a corridor; however, the requirements apply when the door exits into a stair enclosure. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   If an exit meets the requirements of a corridor as defined in UBC 1004.3.4, does it also need to meet the requirements of an exit enclosure as defined in UBC 1005.3.3.5?
A:  

No, the two satisfy different requirements. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Can a corridor include stairs that are otherwise not required to be enclosed?
A:  

Yes. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Fire Dampers in non-rated ceilings. We are installing new furnaces and new ductwork into a church where none of the ceilings are fire rated. They should be fire rated but the church is over 50 years old. In most jurisdictions, because the ceiling is not rated, we would not have to put fire dampers in the registers that penetrate the ceiling because it would not add any protection-a fire would just burn around the dampers. One jurisdiction is requiring us to put in fire dampers, reasoning that the ceiling should be fire rated and so we have to put them in based on what it should be. This does not seem consistent with other jurisdictions. We also recently did a job in a jurisdiction in which we did not need to install fire dampers or even smoke/fire dampers in the hallways because the building already had a sprinkler system. Yet a half-mile away-in another jurisdiction, the Fire Marshall-in an inspection of a church, required that the church add fire dampers (not smoke/fire dampers) to all of the hallway ceiling registers. What is right? Referred from the August 9, 2001 Mechanical Code Forum.
A:  

When a fire-rated construction is penetrated, fire dampers are required. If the construction is not fire rated (as per 713.11 & 711.4) fire dampers are not necessary. In cases like these where the ceilings were not rated, smoke/fire dampers should not have been required. In these cases, the Plans Examiner required fire dampers because the existing 50-year-old ceiling should be fire-rated by today's standards. It is important to note that we cannot base code requirements on our wishes or what we feel "should be." (September 6, 2001 Tri-County Building Code Forum)


Q:   Our department would classify a 14,000-square-foot building that houses a city or county library A-3, however, some architects say that such buildings in the tri-county area have been classified B with some accessory A uses. What is the correct classification?
A:  

Typically, libraries are "B" occupancies. But many contemporary libraries are designed for multiple uses beyond the traditional book lending and study areas to community meeting rooms and even city council chambers. In such cases, other occupancies may apply. The code panel strongly recommends that design professionals contact the building-department jurisdiction during the conceptual phase. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Recently, there has been some discussion regarding the classification of a Library. Given 14,000 s.f. Library (City or County) I would classify this building as an A-3. However, some architect's claim that such buildings in the Portland area have been classified as a B with some accessory A uses. Could you add this as a question at the building code forum?
A:  

A-3 or A-2.1 based on occupancy. You look at the predominate use of the building for assigning a use group to the building. For incidental uses of the building, their percentage of the whole area need to be determined. If the accessory /incidental use is less than 25 percent then the predominant use of the building is the main use. When you have an area where people are assembling, which in the case of a library is true, you have to classify it under Assembly use group. (Tri-County Building Code Forum, December 17, 2001)

 

The following Q and A is a reconsideration of a previous code forum answer on the subject


Q:   Should a building department accept drawings prepared by an engineer or architect but not stamped by them? In other words, is an engineer or architect required to stamp final documents when the building is exempt from the Architect's Law? How many sets of documents must carry a "wet signature"?
A:  

OAR 806-010-0045. No. An Oregon registered architect is required to stamp and sign all his or her work in this state regardless of its exemption status. Only one set of submittal documents must bear the wet signature of the architect or engineer. It is permissible for the professional stamp or seal to be electronically duplicated. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   Are the parking provisions of OSSC 1104 retroactive?
A:  

No. You must still comply with Federal ADA requirements. These requirements were retroactive in OSSC till October 1, 1996 as can be seen from the language in Section 3101(e) of the 1993 OSSC which, states "Except as required in Section 3104 for accessible parking, this code is not retroactive…". When the 1996 OSSC was adopted effective October 1, 1996, the retroactive code requirement for accessible parking were dropped from the OSSC. (Tri-County Building Code Forum, December 17, 2001)


Q:   How does Chapter 13 relate to a new packaged A/C installation on an existing building?  Specifically, is the minimum EER rating 12.5 or 10.9? The footnotes to Table 13-N on page 140.36 of the 4/1/04 version of Chapter13 refer to "New Construction" and "replacements."  It is not clear which category would apply in our case.  This is not a replacement but a new system, including all new ducts, to be installed in an existing building. This unit will provide additional cooling and ventilation for an existing tenant space and serve a newly created tenant space within an existing building.
A:   Use the calculation for new construction. (Tri-County Code Forum, December 2004)
Q:   The IBC, 502.1 defines Building Area as "The area included within surrounding exterior walls..." In calculating the allowable area, is the area of the exterior walls to be included, or just the interior area exclusive of the exterior walls?
A:  

For the purposes of calculating the allowable area in OSSC section 503, the IBC Commentary says that the allowable area is the inside face of the exterior wall. However, the panel refers this question to the state for interpretation: www.bcd.oregon.gov/programs/structural/interps/OSSC_Interp_503_area_of_building.pdf 
(Tri-County Code Forum June 2005)


Q:   Will the text given in 302.2.1, which states that assembly spaces that are accessory uses to Group E are not required to be considered separate occupancies be interpreted in Tri-County to mean that there is no occupancy separation required?  Table 302.3.2 indicates separation is required (2-Hour) which seems to be in conflict with 302.2.1. The spaces we are curious about typically include gymnasiums, school cafeteria, and possibly school library.
A:   The code section refers to assembly occupancies that are accessory to Group E, in which case they are not required to be separated. If, by chance, there was an A occupancy adjacent to the E, but under separate control, then they would need the appropriate occupancy separation. (Tri-County Code Forum, September 2004)
Q:   Paragraph 303.1 states that assembly spaces which are accessory to Group E in accordance with 302.2 are not considered assembly occupancies. Will that be the case for K-12 public school buildings in Tri-County? If yes, are these uses classified as E for the purposes of determining occupant load, egress width, etc.?
A:   Section 302.3.1 states that for non-separated uses, all other code requirements shall apply to each portion of the building based on the use of that space. The exiting requirements for the assembly portions of the building need to meet the requirements based on that use. (Tri-County Code Forum, September 2004)
Q:   Please clarify the definition of atrium per 404.1.1 as it relates to an opening in a two-story building.
A:  

The definition in the 2004 OSSC of what constitutes an "atrium" is nearly identical to that found in section 202 of the 1998 OSSC. However, the  companion provisions for "shafts" and "vertical exit enclosures" in the respective code editions have changed considerably.

 

For example, section 711.3 of the 1998 OSSC stated that; "In other than Group I Occupancies, openings that penetrate only one floor and are not connected with openings communicating with other stories or basements and that are not concealed within building construction assemblies need not be enclosed." As such, most required stairways were permitted to atmospherically connect two floors.

 

In contrast, section 707.2, exception 7.2 of the 2004 OSSC will not allow the "required means of egress system" to be unenclosed  between floors except as permitted in section 1019.1. A cursory look at section 1019.1 reveals that the required stairways in the means of egress must be enclosed except for the following circumstances:

 

In other than Group H and I occupancies, a stairway serving an occupant load of less than 10 not more than one story above the level of exit discharge.

In other than occupancy Groups H and I, a maximum of 50 percent of egress stairways serving one adjacent floor are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Any two such interconnected floors shall not be open to other floors.

 

In other than occupancy Groups H and I, interior egress stairways serving only the first and second stories of a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Such interconnected stories shall not be open to other stories.

 

In short, where a sprinkler system is installed, stairways serving the first and second stories may be unenclosed. In unsprinklered buildings, 50 percent of the egress stairways and stairways serving 10 or less persons above the level of exit discharge may be unenclosed.

 

As noted, this is only one example of the differences. Sections 404, 707.2 and 1019.1 contain additional exceptions that warrant further examination and application. (Tri-County Code Forum, March 2005)
Q:   For purposes of applying the requirements for natural light, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural light from the living/dining area?
A:   Yes, if it meets the qualifications of the opening described in Section 1205.2.1. of the 2004 0SSC. (Tri-County Code Forum, September 2004)
Q:   Assuming the "den" is not provided with mechanical ventilation, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural ventilation from the living/dining area?
A:   Yes, if the opening meets the minimum opening requirements of Section 1203.4.1.1 of the 2004 OSSC . (Tri-County Code Forum, September 2004)
Q:  

1-4. Code References: 

Section 310.4  Basements in dwelling units and every sleeping room below the fourth story shall have at least one operable window or door approved for emergency escape or rescue that shall open directly to a public street, public alley, yard or exit court.

 

Section 1204.2  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural light by means of exterior glazed openings with an area not less than one tenth the floor area of such rooms with a minimum of 10 square feet.


Section 1204.3  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural ventillation as specified in section 1203.2.4 or by a mechanical ventilation system which shall be capable of supplying ventilation air in accordance with Table 12-A.

 

Section 1204.1  For the purpose of determining the light or ventilation and source control ventilation for Group R Occupancies required by this section and Table 12-A, any room may be considered as a portion of an adjoining room when one half of the area of the common wall is open and unobstructed and provides an opening of not less that one tenth of the floor area of the interior room or 25 square feet, whichever is greater.

 

The floor plans for dwelling units each have an interior room labeled as a "den." In one unit the "den" has a clothes closet. The "den" in the other unit does not have a closet. Assuming these units are not in a building complying with the requirements of chapter 4 for a high rise building, please respond to the following questions:

 

Is the "den" containing the clothes closet considered a sleeping room for purposes of applying emergency egress requirements?  Is the "den" that does not contain a closet considered a sleeping room for purposes of applying emergency egress requirements?

A:   The applicant is required to label the rooms accurately. If the room has a closet and is labeled "den," building departments should accept the designation and make no assumption that it will be used other than how it is labeled. For example, many living rooms have closets but are not treated as sleeping rooms. (Tri-County Code Forum, September 2004)
Q:   We have a clarification request for the next Building Code Forum.  One of our colleagues recently found the following: Under section 105.2 Exceptions 13 (Agricultural Structures) and 14 ( Equine Facilities), the new code refers to ORS 455.310. ORS 455.310 covers exempt residential construction, not agricultural structures. ORS 455.315 covers exempt agricultural structures. See ORS index at http://www.leg.state.or.us/ors/455.html You may want to point this out so that it is addressed in future issuances of the Code.
A:   The wrong statute was cited in the code and will be corrected. (Tri-County Code Forum, March 2005)
Q:   What are the new OSSC requirements for firewalls in apartments?
A:   The new code requires the dwelling unit separation to be one hour, unless the building is sprinkled; then unit separation can be 30 minutes. See also section 708. (Tri-County Code Forum, June 2005)
Q:   Is there a definition for a 30-minute wall?
A:   Table 721.6.2 of the OSSC  assigns a fire-resistive time period to various wall components. Using this table, a designer is able to establish an overall fire-resistive time period for a given assembly by adding up the times assigned to interior and exterior membranes, the wood frame and the addition of certain insulations (unique to wood frame construction). (Tri-County Code Forum, June 2005)
Q:   If the 2-1/2 inch net section is still required by the 2004 Structural Specialty Code, does the minimum net section apply to metal plate connected pre-engineered roof trusses used to anchor masonry or concrete walls?
A:   The prescriptive provisions have been replaced with design provisions. (Tri-County Code Forum, June 2005)
Q:   For ADA access, the code requires 12 inches adjacent to the ?push? side of a door equipped with a closer and a latch. If the latch is panic hardware, is the 12 inches of adjacent space still required?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   When there are several properties under the same ownership how do you treat property lines?
A:   Contact your local jurisdiction. The answer depends on which jurisdiction you?re in and must be judged on a case by case basis. Suggestions from the panel included the use of a covenant (not to sell separately) or a lot line adjustment. (Tri-County Code Forum, September 2004)
Q:  

Are there situations in which an accessible table located adjacent to a bar counter can be provided instead of a 60-inch long portion of the bar counter lowered to 34 inches?

Bar counters in restaurants and lounges are usually 36 to 44 inches high where patrons sit on raised seats. Ice and drink dispensers, coolers, sinks, and other equipment are typically built into the barkeep side of the casework. It is common for small restaurants to propose a 6 to 8 foot long bar.

 

Section 1108.4.5 completely eliminates raised bar counters that are 5 feet long or less. Bar counters less than 10 feet long are impractical because the remaining raised portion is less than 5 feet long. The end result is the restaurant does not have a raised bar, which seems overly restrictive.

 

Note that The Americans with Disabilities Act Accessibility Guidelines (ADAAG) Section 5.2 allows bar service to be provided at accessible tables within the same area as the raised counter.

A:  

Section 1101.6 references ORS 447.250 and allows waivers or modifications if the code section is more restrictive than ADA guidelines or the Fair Housing Act. If the new ADAAG guidelines allow this alternate method, the applicant may be able to appeal to the state. It could also be approved at the local level as an alternate method, but jurisdictions may be hesitant to make this approval without guidance from the state.

 

It would seem that if a table is assigned for use as an "accessible table" and is made available for use when needed that it could fulfill the requirement. However, if the table was in use and was then needed, it could create a slight inconvenience as the current patrons would have to be relocated to make room for the physically challenged user. (Tri-County Code Forum, September 2004)


Q:   Our current project is the restoration of a fire-damaged school. Would this work be considered a "repair," an "addition," or an "alteration"? While most of the project consists of rebuilding the classrooms and does not include adding any new space, the original structure is more than 65 years old and could use some structural updates, as well as the addition of an smoke alarm system. Would such additions change the category of construction?
A:   The work to restore the fire-damaged area would be considered a repair, even if new trusses must be added to be sufficient to carry the load. The fire code  has a retroactive provision that requires smoke alarms in all such buildings. Work with your local building official to discuss details. (Tri-County Code Forum, June 2005)
Q:   Do S2 parking structures need to be sprinklered?
A:   406.4 and 903.2.9 Open, no; enclosed, yes. (Tri-County Code Forum, June 2005)
Q:   Does the shape of the ceiling tiles, whether they are flat or regular, have a  bearing on the grid requirements?
A:   No. (Tri-County Code Forum, June 2005)
Q:   Can tiles be scribed in at all sides and not affect the deflection of the grid?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   If a ceiling grid system has no tiles or lights directly attached to the grid, does it then become an aesthetic system and not need to meet any of the ceiling grid code requirements?
A:   Any such grid system must meet the structural code requirements. (Tri-County Code Forum, June 2005)
Q:   Please clarify 1621 and referenced ASCE 9.6.2.6.2.2 as it relates to suspended ceiling tile and sprinkler head design.
A:   The panel refers this question to the Building Codes Division for interpretation. It appears that it is extremely difficult for builders to locate sprinklers or seismic joints that are the correct size. (Tri-County Code Forum, March 2005)
Q:   What is the requirement for upper cabinet height?
A:  

UFAS (Kitchen storage) states that " Max. height shall be 48inches for at least one shelf of all cabinets & storage shelves mounted above work counters.? Does that mean one shelf of EACH upper cabinet? Or does that mean just one shelf is required to be mounted at 48 inches and the others can be mounted higher?


UFAS is not the adopted accessibility standard in the State of Oregon. However,  OSSC 1109.11.2, which is based on the Americans with Disabilities Act Architectural Guidelines (ADAAG), requires 50 percent of the cabinets to have at least one shelf within the height limitation. (Tri-County Code Forum, June 2005)


Q:   I have a question for further clarification on a ventilation question related to the Q&A posed during the April 8 forum and answered in the August-October 2004 News Site, specifically Oregon Structural Specialty Code, Section 1505. Can alternate ventilation (gable end vents or extra vents in non-vaulted areas) be installed to compensate for any blocked or restricted soffit vents, due to insulation filled rafter or scissor truss cavities, and achieve a 150:1 venting requirement? Any 2x6, 2x8, 2x10 rafter, for a vaulted ceiling, is simply too small to allow for R-30 Fiberglass Batt insulation and allow 1" air gap. (R-30= 9-1/4(one quarter)" for high density fiberglass insulation, 2x10 =9-1/4(one quarter)"   there is no room for air gap) Any scissor truss is only 3-1/2(one half)" at the soffit vent, and there is no possible way to achieve either R-30 or the required air gap for the first 18" to 36" of the scissor truss cavity (depending upon pitches) There is a conflict between structural codes allowing 2x4 trusses, 2x6, 2x8 and 2x10 rafters, the insulation requirements and ventilation requirements. The insulation gets crammed into rafter spaces and venting is blocked off. When scissor trusses or less than 2x12 rafters are used, the plans examiner should be able to know that mathematically the soffit vents will be blocked. Shouldn't this be the step when alternate venting should be called out? How do we meet all three requirements? We have had call-back on houses that "meet codes" and were signed off, but now have high moisture build-up in the attic and mold growth on the roof sheeting. Obviously the current venting is not working!
A:   The code allows for the compression of roof insulation in sloped roof assemblies in proximity to eave vents. The code also requires the installation of "baffles" in order to maintain cross ventilation. (Tri-County Code Forum, December 2004)
Q:   Please clarify the definition of "walls directly attached to structure."  Do walls that are braced to the structure meet his requirement?
A:   If the wall is bracing a building, or it is relying on the building for its support, it is a part of the structure. (Tri-County Code Forum, June 2005)
Q:   What if you re-stripe?
A:  

If you're repainting the existing stripes in an existing lot over the existing stripes, that is fine, the repainting of the stripe can be to match existing stripes. If you want to move spaces or change the configuration, you can do so as long as you comply with the code in existence at the time of reconfiguring the parking lot. (Tri-County Building Code Forum, December 17, 2001)


Q:   The 1998 Structural Specialty Code based on the 1997 UBC Section 1633.2.8.1. Item 5 requires that wood elements of a concrete or masonry wall anchorage system "have a minimum actual net thickness of 2 1/2 inches."  Does the current 2004 Structural Specialty Code based on the 2003 IBC have an equivalent requirement?  If yes, where is the citation requiring 2-1/2 inch (3x)wood elements for the anchorage of concrete or masonry wall systems?
A:   No. There is nothing in the current code that addresses this issue. (Tri-County Code Forum, June 2005)

Fire Rated Components

Q:   There is widespread inconsistency in accessibility requirements. Some jurisdictions have issued accessibility interpretations while others don't even review accessibility details in the documents saying that this is a federal civil law.
A:  

The Building Official, by ORS 447, is responsible to enforce these provisions (Chapter 11) of the code. Therefore all jurisdictions should provide accessibility guidelines for plan review and provide comments to the applicant during the plan review process. Beginning Sept. 1, Tri-County jurisdictions are required to use the commercial application checklist and process. This process provides the opportunity for a pre-submittal meeting during which the jurisdiction can outline the accessibility requirements of the project, using the commercial application checklist as a guide.(September 6, 2001 Tri-County Building Code Forum)


Q:   Is it permissible to compare only base shear values for wind and earthquake loads to decide whether wind or seismic loads govern the design?
A:  

No, it is not permissible. A correct analysis requires determining both the earthquake loads and the wind loads on an element of a structure. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For an existing building being relocated with no interior remodel or change of use, what are the upgrade requirements by code?
A:  

Section 3404 of the OSSC addresses "moved buildings" as does ORS 455.410 entitled "Relocated Buildings; Substantial Compliance Required; Permits." The statute states that "existing buildings or structures which are removed from their foundation and relocated to another site within this state shall be in substantial compliance in accordance to the statute." In short, the statute recognizes moved buildings as existing structures. This statute defines "substantial compliance" and addresses upgrade requirements in terms of foundation construction, installation upgrades, smoke detection and permit requirements. The statute requires the new foundation to fully comply with current building codes. It also requires the ceiling and underfloor insulation to be upgraded to current levels. It requires the installation of smoke alarms at all locations the code imposes for new construction, but only requires the alarms to be hardwired and interconnected when wall and ceiling finishes have been removed, much like we see with residential alterations. The jurisdiction cannot require existing windows (or other elements) to be upgraded for reasons of energy code compliance or to meet egress requirements. The only time a jurisdiction can require upgrades is in the case where the moved structure is altered and then only those portions that are altered must be upgraded. For example, let's say an existing 3-bedroom dwelling is relocated to a new site. The plans show that the kitchen will be remodeled as will the master bedroom. The master bedroom shows a new window being installed but the other 2 bedrooms show no alterations. The Plans Examiner knows that the windows in the other 2 bedrooms have a sill height of greater than 44" above the finish floor and thus do not meet current code. Can the examiner require the master bedroom window to meet egress? Yes, because is it is "new" and not a part of the "existing" dwelling. Can the examiner require the windows in the other two bedrooms to be replaced? No, because they are existing.

(September 6, 2001 Tri-County Building Code Forum)


Q:  

There are some jurisdictions in the Tri-County area that accept single user, unisex toilettes in "A" occupancy while others don't.


Background: When this issue is not resolved until building permit application time, it is very difficult to resolve in a building that has been fully designed.

A:  

Section 101.3 (Scope) incorrectly identifies Appendix Chapter 29 as being adopted. When the code was last modified, provisions of the appendix chapter were brought forward to the regular chapter eliminating the need for the appendix chapter. However, Table 29-A is adopted by reference in Section 2902.2. To be clear, only Table 29-A is adopted. That said, occupancies are required to have restrooms in the number determined by Chapter 29 and Table 29-A. Section 1108.2.2 imposes an additional requirement that an accessible, unisex toilet facility be provided where an aggregate of six or more male and female water closets are required in "A" occupancies, recognizing that in larger facilities it is likely that a disabled person might require assistance by a member of the opposite sex. In "M" occupancies, the required number of toilets may be much lower; in fact, a single-occupant unisex accessible restroom might fulfill all code requirements. Finally, in existing facilities, where it is impractical to fully comply with the code, Section 1113.3.7.1 may be invoked. This section allows one unisex facility in lieu of making existing facilities accessible. See 2904.2, which deals with the substantial alteration of existing Group A occupancies. The building official may approve substantial alterations without the installation of additional water closets only where it is structurally unfeasible to make such alterations. (September 6, 2001 Tri-County Building Code Forum)


Q:  

In a multistory rated building some jurisdictions require a "lid" on the bottom side of a private balcony while others do not.


Background: This typically occurs in a Type-V One-Hour, R-1 occupancy and multistory buildings where there are unit balconies that stack. It is generally agreed that even when using pressure treated materials, enclosing these decks on the underside will rapidly lead to deterioration in our moist climate. Venting these areas on the horizontal surface is not permitted in the code. Face vents are problematic. This issue regards conventional construction and not the use of heavy timber. It also deals specifically with private balconies, not exterior exit balconies.

A:  

Section 705 (Projections) speaks to architectural appendages beyond the floor area and thus applies to exterior balconies. Projections from Type-V construction may be of combustible or noncombustible construction. These projections are only required to be protected with one-hour fire resistive construction where openings are required to be protected or where they are prohibited. Therefore, balconies (other than exterior exit balconies) can be of unprotected construction. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do older buildings require seismic upgrading?
A:  

Portland has an ordinance requiring the seismic upgrading of un-reinforced masonry buildings that the City has specifically listed. Nothing in the code mandates such upgrades, but the code does give guidance about providing the upgrades. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Can a uniform commercial re-roofing permit and procedure be developed for tri-county area?
A:  

Mr. Watts with Associated Roofing Contractors posed this question. He represents commercial roofing companies in the tri-county region. The roofing association would like consistency and a uniform approach to handling re-roofing projects in the tri-county area. Mr. Watts mentioned some jurisdictions require engineering reports and some do not and noted that consistency also varies among jurisdictions regarding pre-inspections.

The panel forwarded this issue to the Tri-County Processes and Forms committee for discussion and action. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   What occupancy classification should be assigned to a dining/drinking establishment that contains more than one room each with an occupant load of 49 or less but with a total combined occupant load exceeding 50 and with room having one code compliant exit? Are there any restrictions on how large the openings between rooms can be? (See attatched diagram) Occupancy Classification

Code Reference: Section 302.1.1 defines an A-3 Occupancy as: "A building or portion of a building having an assembly room (emphasis added) with an occupant load of less than 300 without a legitimate stage, including such spaces used for educational purposes and not classified as Group B or E Occupancies."

Section 304.1 defines B Occupancies as: "Group B Occupancies shall include buildings, structures, or portions thereof, for office, professional or service type transactions, …, and eating and drinking establishments (emphasis added) with an occupant load of less than 50."

Table 10-A item 4 lists dining rooms and drinking establishments as less concentrated assembly areas using an occupant load factor of one person per 15 square feet and requires two exits when the occupant load is at least 50 persons.

A:  

Given the information submitted to the forum, the majority of the group felt the appropriate occupancy group is A-3, based on occupants' ability to migrate from space to space. It is important to note, however, that Section 301 assigns responsibility to the Building Official to classify a space or group of spaces, when the use isn't clear. The code panel members agreed that more information was needed to properly consider this question. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   In the Tri-County Checklist Section 5.0, items 5.20, 6.20, and 7.20 require structural calculations for vertical loads for equipment weighing more than400 pounds. Wouldn't any load beyond what was factored into the original design on the manufactured roof require an engineered design? If not, who would be liable for the added loading? If it is determined that all loads on manufactured roofs require engineered designs, shouldn't the Tri-County Checklist be revised so that applicants don't have to find out at the permit counter that they need an engineer for a 200-pound roof-top unit?
A:  

See OSSC, Volume 2, Section 1632.1. The 400 pound designation identified in this section refers only to seismic bracing. The structure must be capable of supporting the imposed gravity loads, and it may be necessary to provide a design proving that The code panel sent a revision request to the Tri-county Processes and Forms Committee (?) for review and action. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For plans with engineered lateral-load-resisting elements, how should we apply the use of "drag struts" or "collectors" to load-resisting elements such as shear walls or frames?
A:  

Plans with non-prescriptive (engineered) lateral-load-resisting elements must show sufficient load-transfer mechanism detail to provide a continuous load path. This may include drag struts, collectors, and blocking and strapping at re-entrant corners. (Tri-County Commercial Structural Building Code Forum, March 21, 2002


Q:   Section 1003.3.3.6 states: "Handrails shall be continuous the full length of the stairs..." Does that mean if there are landings within the flight of stairs that the handrail(s) shall be required to continue through the length of the landings?
A:  

No. Section 1003.3.3.1 stipulates that stairway includes stairs, landings, handrails and guardrails. All of these four components constitute a stairway. Section 1003.3.3.6 requires the handrails to be continuous for the full length of the stairs, not the stairway. With each intervening landing, you start new stairs. The handrail must still terminate properly and meet the other requirements of Section 1003.3.3.6. (Tri-County Building Code Forum, December 17, 2001)


Q:  

Can an exterior deck or balcony that is only accessed through an individual dwelling or guest unit in an Group R Division 1 Occupancy be considered as "within individual dwelling units" and therefore require only a 36 inch high guardrail?

 

Background: This question regards exterior deck or balcony guardrails for individual R-1 Occupancies. Section 509.2 of the OSSC states: "The top of guardrails shall not be less than 42 inches (1067 mm) in height. However, exception # 1 states: The top of guardrails for Group R, Division 3 and Group U, Division 1 Occupancies, and interior guardrails within individual dwelling units, Group R Division 3 congregate residences and guest rooms of Group R, Division 1 Occupancies may be 36 inches.

A:  

No. The code section referenced answers the question. The guardrail is not within the dwelling unit. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a one-hour rated wood frame floor-ceiling or roof-ceiling assemblies some jurisdictions require fire taping of the second (exposed) layer of gyp board while others do not.

Background: This question assumes that the gypsum board will be concealed either by surface applied materials or a suspended non-rated ceiling. It also assumes that the joints between the layers of gypsum board are staggered.
A:  

The builder needs to install per the approved assembly as prescribed by the approving agency. There may be several assemblies that are approved which can and do differ in their specific requirements. Build it as prescribed. (September 6, 2001 Tri-County Building Code Forum)


Q:   Is it the intent of the OSSC section 904.2.9 to sprinkler new apartments / condominiums three or more stories in height, even if the first floor contains a parking garage (U-1) that has the properly installed occupancy separations?
A:  

Yes. In the code, the definition of an apartment house is any building or portion thereof that contains three or more dwelling units. For the purpose of this code, that includes residential condominiums. Note that this definition refers to buildings that contain dwelling units. It does not exclude portions of the building other than dwelling units. Therefore, mixed occupancy buildings that are three or more stories in height which meet the definition of apartment house must be provided with an automatic sprinkler system throughout the entire structure. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a multistory wood-frame building some jurisdictions require one layer of 5/8 type X gypsum wallboard on the bottom of TJI joists, while others require two layers.
Background: This question concerns one-hour rated floor ceiling assemblies using pre-manufactured wood I-Joists. The assumption is that other elements of the assembly are followed. It also pertains to the lighter wood I joists rather than the TJI 55 series which has a NER tested assembly that permits a single layer outright. One key to this issue is the exchange of RC-1 channels and furring channels in the various assemblies.
A:  

Gypsum wallboard details, like the fire stopping details, need to be reviewed and agreed upon in advance. They are determined by the criteria found in the Gypsum Association manual Fire Resistance Design Manual and other approved sources such as Underwriter's Labs etc. In Tri-County, such details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the product, and to have it reviewed and approved, nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:  

Some jurisdictions allow fire-stopping methodology to be resolved in the field with a pre-installation meeting involving the affected parties. Other jurisdictions require fire-stopping details to be shown on the construction documents.


Background: The question here is not whether fire-stopping is required or not. Nor is it one that the general parameters for fire-stopping should not be laid out in the construction documents. Some jurisdictions however recognize that specifications and details may not reflect actual job conditions nor will they necessarily be drawn around the particular supplier of the fire-stop material.

A:  

Fire-stopping details need to be reviewed and agreed upon in advance, and must follow the manufacturer's instructions. In Tri-County, fire-stopping details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the appropriate product and to have it reviewed and approved nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do the sprinkler substitutions allowed in OSSC Section 508 allow the minimum one hour fire resistive protection mandates of OSSC 704.4 (requires members carrying masonry or concrete walls in buildings over one story in height to be a minimum of one hour fire-resistive construction or the fire-resistive requirements of the wall) to be waived as well?
A:  

No. 508 is a general requirement. 704.4 is a specific requirement and even applies to a non-rated building. Therefore you have to provide the one-hour protection or the fire-resistive requirement of the wall, whichever is greater. (Tri-County Building Code Forum, December 17, 2001)


Q:   For multifamily Type V - 1-HR building, do the interior closet walls need to be 1-hr construction? How about bathroom doors, closet doors, cabinets, etc.?
A:  

No. As long as you comply with Section 601.5.2.2 Hotels & Apartments, which states: "Interior nonbearing partitions within individual dwelling units in apartment houses and guestrooms or suites in hotels when such dwelling units guest rooms or suites are separated from each other and from corridors by not less than one-hour-fire-resistive construction may be constructed of: (2) Combustible framing with noncombustible materials applied to the framing in buildings of Type III or V construction.

As for bathroom doors, closet doors, cabinets etc. Section 601.5.5 Trim, states: "…Unprotected wood doors and windows may be used except where openings are required to be fire protected." (Tri-County Building Code Forum, December 17, 2001)


Q:   There are inconsistent code requirements for ventilation fans in row house construction. Every jurisdiction requires an under house fan, but some jurisdictions have required a squirrel fan, and some only require a normal bath fan. There should be a consistent requirement for the type and style of fan. Referred from the October 4, 2001 One and Two Family Code Forum.
A:  

Any fan applicable to the conditions will work-as long it meets the building code CFM rating. (Tri-County Building Code Forum, December 17, 2001)


Q:   Sometimes there are multiple permits for one job. When one permit is phoned in for an inspection, the inspectors take out all the permits and perform inspections on permits for which no inspection was requested in addition to the one which was requested. Staff is concerned that the other permits will not be inspected and that the contractor will cover the work. Is this appropriate? Should not all permits be phoned in separately for inspection?
A:  

No, it is not appropriate for inspectors to perform inspections on permits for which no inspection was requested. Yes, all permits should be phoned in separately for inspection; it is not up to the inspector to determine when the work is done; this is the responsibility of the contractor. When a contractor covers work that should be inspected it is a compliance issue that should be dealt with separately. (June 19 Tri-County Electrical Code Forum)


Q:   When is standby power required for egress illumination?
A:  

See 1003.2.9.2, "Power supply." (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   If the intent of the code is to provide the most direct egress for occupants, when is an enclosed vertical exit beneficial?
A:  

When such access serves three or more floors. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:  

Are these requirements applicable to an exterior door opening into a breezeway as described below:

 

Description - A three-story R-1 occupancy with stairways that provide egress from individual dwelling units to the public way or yard. The stairway is approximately 8 feet wide and 60 feet long with both ends fully open to the yard. The stairway is classified as interior because it does not meet UBC 1006.3.3.1 requirements for an exterior stairway.

UBC 1005.3.3, Exit Enclosures, requires interior stairways to be enclosed according to UBC 1005.3.3.3. The exterior openings may be unprotected where permitted by Table 5-A. In this case, unprotected exterior openings area allowed by Table 5-A and then only the walls separating the dwelling units from the exit are required to be fire rated.

UBC 1005.3.3.5, Openings and Penetrations, requires that the doors meet temperature-rise limitations: "All interior exit doors in an exit enclosure shall be protected by a fire assembly having a fire-protection rating of not less than one hour where one-hour-enclosure construction is permitted in Section 1005.3.3.2 and one and one-half hours where two-hour-enclosure construction is required by Section 1005.3.3.2. Such doors shall be maintained self-closing or shall be automatic closing by actuation of a smoke detector as specified in Section 713.2. All hold-open devices shall be listed for the intended purpose and shall close or release the fire assembly to the closed position in the event of a power failure. The maximum transmitted temperature end point for such doors shall not exceed 450? F (232?C) above ambient at the end of 30 minutes of the fire exposure specified in UBC Standard 7-2.

A:  

The temperature - rise limitation is required only for doors in an exit enclosure - not doors in a corridor. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Some jurisdictions waive the drinking fountain requirement in certain occupancies while others don't.

Background: This issue is primarily limited to occupancies in conjunction with R-1 occupancies. Another contributing factor is the availability of alternate sources of liquid. These alternate sources could be beverage bar, as our office has found in senior facilities or motels with continental breakfast.
A:  

A drinking fountain is required to be provided in an "A" and "E" occupancy on each floor level at an approved location (OSSC 2903.2). The only exception is "IN" a drinking or dining establishment. If there exists a conference area with a lobby/foyer, a drinking fountain shall be installed to serve the conference area. A drinking fountain is not required in the drinking or dining establishment portion of the "A" occupancy. Portable facilities or temporary facilities, such as water coolers or bottled water dispensers are not acceptable as alternatives as they can be easily removed or discontinued. Continental breakfast bars and juice bars, which may or may not be open to the public all day, do not qualify as eating or drinking establishments; thus they do not eliminate the requirement for a drinking fountain. (September 6, 2001 Tri-County Building Code Forum)


Q:   A corridor is part of an exit system, and is fully enclosed by walls, floor, ceiling, and protected openings according to UBC 1004.3.4.3. What is the difference between UBC 1004.3.4, Corridors, and 1005.3.3, Exit Enclosures?
A:  

A corridor is a portion of the exit access that leads occupants of a building to an exit. Though the term "corridor" is not defined in the code, it may be helpful to think of a corridor as being similar to a hallway: it provides access to various portions of a building and also provides access to the exterior. In multi-story buildings, corridors typically lead occupants to a stairway that leads to the ground floor. When this stairway serves three or more floors, Section 1005.3.3 requires the stairway to be located in a fire-rated enclosure called an "exit enclosure". The fire rating for the enclosure varies, depending on the type of construction and other factors. All openings leading into the exit enclosure must be fire-rated as well. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   UBC 1004.3.4. Corridors: Under what conditions does a corridor as defined in UBC 1004.3.4 become an exit enclosure as defined in UBC 1005.3.3? JSS: why does the question start with a ref to 1004.3.4, but that is not what the question refers to? Typo.
A:  

Corridors and exit enclosures are independent systems. A corridor becomes an exit enclosure when the corridor leads into or ends at a stair tower required to be an exit enclosure. UBC 1005.3.3. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Please provide the definition of attic space as it pertains to a panelized roof structure and insulation/holder assembly.
A:  

This question was referred to the State Building Codes Division for interpretation. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Are the UBC 1005.3.3.5 requirements for temperature-rise-limited doors applicable to an exterior door that exits into a corridor open to the exterior at both ends? For example, a door on an exterior wall but within a breezeway..
A:  

No, not when the door exits into a corridor; however, the requirements apply when the door exits into a stair enclosure. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   If an exit meets the requirements of a corridor as defined in UBC 1004.3.4, does it also need to meet the requirements of an exit enclosure as defined in UBC 1005.3.3.5?
A:  

No, the two satisfy different requirements. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Can a corridor include stairs that are otherwise not required to be enclosed?
A:  

Yes. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Fire Dampers in non-rated ceilings. We are installing new furnaces and new ductwork into a church where none of the ceilings are fire rated. They should be fire rated but the church is over 50 years old. In most jurisdictions, because the ceiling is not rated, we would not have to put fire dampers in the registers that penetrate the ceiling because it would not add any protection-a fire would just burn around the dampers. One jurisdiction is requiring us to put in fire dampers, reasoning that the ceiling should be fire rated and so we have to put them in based on what it should be. This does not seem consistent with other jurisdictions. We also recently did a job in a jurisdiction in which we did not need to install fire dampers or even smoke/fire dampers in the hallways because the building already had a sprinkler system. Yet a half-mile away-in another jurisdiction, the Fire Marshall-in an inspection of a church, required that the church add fire dampers (not smoke/fire dampers) to all of the hallway ceiling registers. What is right? Referred from the August 9, 2001 Mechanical Code Forum.
A:  

When a fire-rated construction is penetrated, fire dampers are required. If the construction is not fire rated (as per 713.11 & 711.4) fire dampers are not necessary. In cases like these where the ceilings were not rated, smoke/fire dampers should not have been required. In these cases, the Plans Examiner required fire dampers because the existing 50-year-old ceiling should be fire-rated by today's standards. It is important to note that we cannot base code requirements on our wishes or what we feel "should be." (September 6, 2001 Tri-County Building Code Forum)


Q:   Our department would classify a 14,000-square-foot building that houses a city or county library A-3, however, some architects say that such buildings in the tri-county area have been classified B with some accessory A uses. What is the correct classification?
A:  

Typically, libraries are "B" occupancies. But many contemporary libraries are designed for multiple uses beyond the traditional book lending and study areas to community meeting rooms and even city council chambers. In such cases, other occupancies may apply. The code panel strongly recommends that design professionals contact the building-department jurisdiction during the conceptual phase. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Recently, there has been some discussion regarding the classification of a Library. Given 14,000 s.f. Library (City or County) I would classify this building as an A-3. However, some architect's claim that such buildings in the Portland area have been classified as a B with some accessory A uses. Could you add this as a question at the building code forum?
A:  

A-3 or A-2.1 based on occupancy. You look at the predominate use of the building for assigning a use group to the building. For incidental uses of the building, their percentage of the whole area need to be determined. If the accessory /incidental use is less than 25 percent then the predominant use of the building is the main use. When you have an area where people are assembling, which in the case of a library is true, you have to classify it under Assembly use group. (Tri-County Building Code Forum, December 17, 2001)

 

The following Q and A is a reconsideration of a previous code forum answer on the subject


Q:   Should a building department accept drawings prepared by an engineer or architect but not stamped by them? In other words, is an engineer or architect required to stamp final documents when the building is exempt from the Architect's Law? How many sets of documents must carry a "wet signature"?
A:  

OAR 806-010-0045. No. An Oregon registered architect is required to stamp and sign all his or her work in this state regardless of its exemption status. Only one set of submittal documents must bear the wet signature of the architect or engineer. It is permissible for the professional stamp or seal to be electronically duplicated. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   Are the parking provisions of OSSC 1104 retroactive?
A:  

No. You must still comply with Federal ADA requirements. These requirements were retroactive in OSSC till October 1, 1996 as can be seen from the language in Section 3101(e) of the 1993 OSSC which, states "Except as required in Section 3104 for accessible parking, this code is not retroactive…". When the 1996 OSSC was adopted effective October 1, 1996, the retroactive code requirement for accessible parking were dropped from the OSSC. (Tri-County Building Code Forum, December 17, 2001)


Q:   How does Chapter 13 relate to a new packaged A/C installation on an existing building?  Specifically, is the minimum EER rating 12.5 or 10.9? The footnotes to Table 13-N on page 140.36 of the 4/1/04 version of Chapter13 refer to "New Construction" and "replacements."  It is not clear which category would apply in our case.  This is not a replacement but a new system, including all new ducts, to be installed in an existing building. This unit will provide additional cooling and ventilation for an existing tenant space and serve a newly created tenant space within an existing building.
A:   Use the calculation for new construction. (Tri-County Code Forum, December 2004)
Q:   The IBC, 502.1 defines Building Area as "The area included within surrounding exterior walls..." In calculating the allowable area, is the area of the exterior walls to be included, or just the interior area exclusive of the exterior walls?
A:  

For the purposes of calculating the allowable area in OSSC section 503, the IBC Commentary says that the allowable area is the inside face of the exterior wall. However, the panel refers this question to the state for interpretation: www.bcd.oregon.gov/programs/structural/interps/OSSC_Interp_503_area_of_building.pdf 
(Tri-County Code Forum June 2005)


Q:   Will the text given in 302.2.1, which states that assembly spaces that are accessory uses to Group E are not required to be considered separate occupancies be interpreted in Tri-County to mean that there is no occupancy separation required?  Table 302.3.2 indicates separation is required (2-Hour) which seems to be in conflict with 302.2.1. The spaces we are curious about typically include gymnasiums, school cafeteria, and possibly school library.
A:   The code section refers to assembly occupancies that are accessory to Group E, in which case they are not required to be separated. If, by chance, there was an A occupancy adjacent to the E, but under separate control, then they would need the appropriate occupancy separation. (Tri-County Code Forum, September 2004)
Q:   Paragraph 303.1 states that assembly spaces which are accessory to Group E in accordance with 302.2 are not considered assembly occupancies. Will that be the case for K-12 public school buildings in Tri-County? If yes, are these uses classified as E for the purposes of determining occupant load, egress width, etc.?
A:   Section 302.3.1 states that for non-separated uses, all other code requirements shall apply to each portion of the building based on the use of that space. The exiting requirements for the assembly portions of the building need to meet the requirements based on that use. (Tri-County Code Forum, September 2004)
Q:   Please clarify the definition of atrium per 404.1.1 as it relates to an opening in a two-story building.
A:  

The definition in the 2004 OSSC of what constitutes an "atrium" is nearly identical to that found in section 202 of the 1998 OSSC. However, the  companion provisions for "shafts" and "vertical exit enclosures" in the respective code editions have changed considerably.

 

For example, section 711.3 of the 1998 OSSC stated that; "In other than Group I Occupancies, openings that penetrate only one floor and are not connected with openings communicating with other stories or basements and that are not concealed within building construction assemblies need not be enclosed." As such, most required stairways were permitted to atmospherically connect two floors.

 

In contrast, section 707.2, exception 7.2 of the 2004 OSSC will not allow the "required means of egress system" to be unenclosed  between floors except as permitted in section 1019.1. A cursory look at section 1019.1 reveals that the required stairways in the means of egress must be enclosed except for the following circumstances:

 

In other than Group H and I occupancies, a stairway serving an occupant load of less than 10 not more than one story above the level of exit discharge.

In other than occupancy Groups H and I, a maximum of 50 percent of egress stairways serving one adjacent floor are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Any two such interconnected floors shall not be open to other floors.

 

In other than occupancy Groups H and I, interior egress stairways serving only the first and second stories of a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Such interconnected stories shall not be open to other stories.

 

In short, where a sprinkler system is installed, stairways serving the first and second stories may be unenclosed. In unsprinklered buildings, 50 percent of the egress stairways and stairways serving 10 or less persons above the level of exit discharge may be unenclosed.

 

As noted, this is only one example of the differences. Sections 404, 707.2 and 1019.1 contain additional exceptions that warrant further examination and application. (Tri-County Code Forum, March 2005)
Q:   For purposes of applying the requirements for natural light, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural light from the living/dining area?
A:   Yes, if it meets the qualifications of the opening described in Section 1205.2.1. of the 2004 0SSC. (Tri-County Code Forum, September 2004)
Q:   Assuming the "den" is not provided with mechanical ventilation, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural ventilation from the living/dining area?
A:   Yes, if the opening meets the minimum opening requirements of Section 1203.4.1.1 of the 2004 OSSC . (Tri-County Code Forum, September 2004)
Q:  

1-4. Code References: 

Section 310.4  Basements in dwelling units and every sleeping room below the fourth story shall have at least one operable window or door approved for emergency escape or rescue that shall open directly to a public street, public alley, yard or exit court.

 

Section 1204.2  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural light by means of exterior glazed openings with an area not less than one tenth the floor area of such rooms with a minimum of 10 square feet.


Section 1204.3  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural ventillation as specified in section 1203.2.4 or by a mechanical ventilation system which shall be capable of supplying ventilation air in accordance with Table 12-A.

 

Section 1204.1  For the purpose of determining the light or ventilation and source control ventilation for Group R Occupancies required by this section and Table 12-A, any room may be considered as a portion of an adjoining room when one half of the area of the common wall is open and unobstructed and provides an opening of not less that one tenth of the floor area of the interior room or 25 square feet, whichever is greater.

 

The floor plans for dwelling units each have an interior room labeled as a "den." In one unit the "den" has a clothes closet. The "den" in the other unit does not have a closet. Assuming these units are not in a building complying with the requirements of chapter 4 for a high rise building, please respond to the following questions:

 

Is the "den" containing the clothes closet considered a sleeping room for purposes of applying emergency egress requirements?  Is the "den" that does not contain a closet considered a sleeping room for purposes of applying emergency egress requirements?

A:   The applicant is required to label the rooms accurately. If the room has a closet and is labeled "den," building departments should accept the designation and make no assumption that it will be used other than how it is labeled. For example, many living rooms have closets but are not treated as sleeping rooms. (Tri-County Code Forum, September 2004)
Q:   We have a clarification request for the next Building Code Forum.  One of our colleagues recently found the following: Under section 105.2 Exceptions 13 (Agricultural Structures) and 14 ( Equine Facilities), the new code refers to ORS 455.310. ORS 455.310 covers exempt residential construction, not agricultural structures. ORS 455.315 covers exempt agricultural structures. See ORS index at http://www.leg.state.or.us/ors/455.html You may want to point this out so that it is addressed in future issuances of the Code.
A:   The wrong statute was cited in the code and will be corrected. (Tri-County Code Forum, March 2005)
Q:   What are the new OSSC requirements for firewalls in apartments?
A:   The new code requires the dwelling unit separation to be one hour, unless the building is sprinkled; then unit separation can be 30 minutes. See also section 708. (Tri-County Code Forum, June 2005)
Q:   Is there a definition for a 30-minute wall?
A:   Table 721.6.2 of the OSSC  assigns a fire-resistive time period to various wall components. Using this table, a designer is able to establish an overall fire-resistive time period for a given assembly by adding up the times assigned to interior and exterior membranes, the wood frame and the addition of certain insulations (unique to wood frame construction). (Tri-County Code Forum, June 2005)
Q:   If the 2-1/2 inch net section is still required by the 2004 Structural Specialty Code, does the minimum net section apply to metal plate connected pre-engineered roof trusses used to anchor masonry or concrete walls?
A:   The prescriptive provisions have been replaced with design provisions. (Tri-County Code Forum, June 2005)
Q:   For ADA access, the code requires 12 inches adjacent to the ?push? side of a door equipped with a closer and a latch. If the latch is panic hardware, is the 12 inches of adjacent space still required?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   When there are several properties under the same ownership how do you treat property lines?
A:   Contact your local jurisdiction. The answer depends on which jurisdiction you?re in and must be judged on a case by case basis. Suggestions from the panel included the use of a covenant (not to sell separately) or a lot line adjustment. (Tri-County Code Forum, September 2004)
Q:  

Are there situations in which an accessible table located adjacent to a bar counter can be provided instead of a 60-inch long portion of the bar counter lowered to 34 inches?

Bar counters in restaurants and lounges are usually 36 to 44 inches high where patrons sit on raised seats. Ice and drink dispensers, coolers, sinks, and other equipment are typically built into the barkeep side of the casework. It is common for small restaurants to propose a 6 to 8 foot long bar.

 

Section 1108.4.5 completely eliminates raised bar counters that are 5 feet long or less. Bar counters less than 10 feet long are impractical because the remaining raised portion is less than 5 feet long. The end result is the restaurant does not have a raised bar, which seems overly restrictive.

 

Note that The Americans with Disabilities Act Accessibility Guidelines (ADAAG) Section 5.2 allows bar service to be provided at accessible tables within the same area as the raised counter.

A:  

Section 1101.6 references ORS 447.250 and allows waivers or modifications if the code section is more restrictive than ADA guidelines or the Fair Housing Act. If the new ADAAG guidelines allow this alternate method, the applicant may be able to appeal to the state. It could also be approved at the local level as an alternate method, but jurisdictions may be hesitant to make this approval without guidance from the state.

 

It would seem that if a table is assigned for use as an "accessible table" and is made available for use when needed that it could fulfill the requirement. However, if the table was in use and was then needed, it could create a slight inconvenience as the current patrons would have to be relocated to make room for the physically challenged user. (Tri-County Code Forum, September 2004)


Q:   Our current project is the restoration of a fire-damaged school. Would this work be considered a "repair," an "addition," or an "alteration"? While most of the project consists of rebuilding the classrooms and does not include adding any new space, the original structure is more than 65 years old and could use some structural updates, as well as the addition of an smoke alarm system. Would such additions change the category of construction?
A:   The work to restore the fire-damaged area would be considered a repair, even if new trusses must be added to be sufficient to carry the load. The fire code  has a retroactive provision that requires smoke alarms in all such buildings. Work with your local building official to discuss details. (Tri-County Code Forum, June 2005)
Q:   Do S2 parking structures need to be sprinklered?
A:   406.4 and 903.2.9 Open, no; enclosed, yes. (Tri-County Code Forum, June 2005)
Q:   Does the shape of the ceiling tiles, whether they are flat or regular, have a  bearing on the grid requirements?
A:   No. (Tri-County Code Forum, June 2005)
Q:   Can tiles be scribed in at all sides and not affect the deflection of the grid?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   If a ceiling grid system has no tiles or lights directly attached to the grid, does it then become an aesthetic system and not need to meet any of the ceiling grid code requirements?
A:   Any such grid system must meet the structural code requirements. (Tri-County Code Forum, June 2005)
Q:   Please clarify 1621 and referenced ASCE 9.6.2.6.2.2 as it relates to suspended ceiling tile and sprinkler head design.
A:   The panel refers this question to the Building Codes Division for interpretation. It appears that it is extremely difficult for builders to locate sprinklers or seismic joints that are the correct size. (Tri-County Code Forum, March 2005)
Q:   What is the requirement for upper cabinet height?
A:  

UFAS (Kitchen storage) states that " Max. height shall be 48inches for at least one shelf of all cabinets & storage shelves mounted above work counters.? Does that mean one shelf of EACH upper cabinet? Or does that mean just one shelf is required to be mounted at 48 inches and the others can be mounted higher?


UFAS is not the adopted accessibility standard in the State of Oregon. However,  OSSC 1109.11.2, which is based on the Americans with Disabilities Act Architectural Guidelines (ADAAG), requires 50 percent of the cabinets to have at least one shelf within the height limitation. (Tri-County Code Forum, June 2005)


Q:   I have a question for further clarification on a ventilation question related to the Q&A posed during the April 8 forum and answered in the August-October 2004 News Site, specifically Oregon Structural Specialty Code, Section 1505. Can alternate ventilation (gable end vents or extra vents in non-vaulted areas) be installed to compensate for any blocked or restricted soffit vents, due to insulation filled rafter or scissor truss cavities, and achieve a 150:1 venting requirement? Any 2x6, 2x8, 2x10 rafter, for a vaulted ceiling, is simply too small to allow for R-30 Fiberglass Batt insulation and allow 1" air gap. (R-30= 9-1/4(one quarter)" for high density fiberglass insulation, 2x10 =9-1/4(one quarter)"   there is no room for air gap) Any scissor truss is only 3-1/2(one half)" at the soffit vent, and there is no possible way to achieve either R-30 or the required air gap for the first 18" to 36" of the scissor truss cavity (depending upon pitches) There is a conflict between structural codes allowing 2x4 trusses, 2x6, 2x8 and 2x10 rafters, the insulation requirements and ventilation requirements. The insulation gets crammed into rafter spaces and venting is blocked off. When scissor trusses or less than 2x12 rafters are used, the plans examiner should be able to know that mathematically the soffit vents will be blocked. Shouldn't this be the step when alternate venting should be called out? How do we meet all three requirements? We have had call-back on houses that "meet codes" and were signed off, but now have high moisture build-up in the attic and mold growth on the roof sheeting. Obviously the current venting is not working!
A:   The code allows for the compression of roof insulation in sloped roof assemblies in proximity to eave vents. The code also requires the installation of "baffles" in order to maintain cross ventilation. (Tri-County Code Forum, December 2004)
Q:   Please clarify the definition of "walls directly attached to structure."  Do walls that are braced to the structure meet his requirement?
A:   If the wall is bracing a building, or it is relying on the building for its support, it is a part of the structure. (Tri-County Code Forum, June 2005)
Q:   What if you re-stripe?
A:  

If you're repainting the existing stripes in an existing lot over the existing stripes, that is fine, the repainting of the stripe can be to match existing stripes. If you want to move spaces or change the configuration, you can do so as long as you comply with the code in existence at the time of reconfiguring the parking lot. (Tri-County Building Code Forum, December 17, 2001)


Q:   The 1998 Structural Specialty Code based on the 1997 UBC Section 1633.2.8.1. Item 5 requires that wood elements of a concrete or masonry wall anchorage system "have a minimum actual net thickness of 2 1/2 inches."  Does the current 2004 Structural Specialty Code based on the 2003 IBC have an equivalent requirement?  If yes, where is the citation requiring 2-1/2 inch (3x)wood elements for the anchorage of concrete or masonry wall systems?
A:   No. There is nothing in the current code that addresses this issue. (Tri-County Code Forum, June 2005)

Building Design

Q:   There is widespread inconsistency in accessibility requirements. Some jurisdictions have issued accessibility interpretations while others don't even review accessibility details in the documents saying that this is a federal civil law.
A:  

The Building Official, by ORS 447, is responsible to enforce these provisions (Chapter 11) of the code. Therefore all jurisdictions should provide accessibility guidelines for plan review and provide comments to the applicant during the plan review process. Beginning Sept. 1, Tri-County jurisdictions are required to use the commercial application checklist and process. This process provides the opportunity for a pre-submittal meeting during which the jurisdiction can outline the accessibility requirements of the project, using the commercial application checklist as a guide.(September 6, 2001 Tri-County Building Code Forum)


Q:   Is it permissible to compare only base shear values for wind and earthquake loads to decide whether wind or seismic loads govern the design?
A:  

No, it is not permissible. A correct analysis requires determining both the earthquake loads and the wind loads on an element of a structure. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For an existing building being relocated with no interior remodel or change of use, what are the upgrade requirements by code?
A:  

Section 3404 of the OSSC addresses "moved buildings" as does ORS 455.410 entitled "Relocated Buildings; Substantial Compliance Required; Permits." The statute states that "existing buildings or structures which are removed from their foundation and relocated to another site within this state shall be in substantial compliance in accordance to the statute." In short, the statute recognizes moved buildings as existing structures. This statute defines "substantial compliance" and addresses upgrade requirements in terms of foundation construction, installation upgrades, smoke detection and permit requirements. The statute requires the new foundation to fully comply with current building codes. It also requires the ceiling and underfloor insulation to be upgraded to current levels. It requires the installation of smoke alarms at all locations the code imposes for new construction, but only requires the alarms to be hardwired and interconnected when wall and ceiling finishes have been removed, much like we see with residential alterations. The jurisdiction cannot require existing windows (or other elements) to be upgraded for reasons of energy code compliance or to meet egress requirements. The only time a jurisdiction can require upgrades is in the case where the moved structure is altered and then only those portions that are altered must be upgraded. For example, let's say an existing 3-bedroom dwelling is relocated to a new site. The plans show that the kitchen will be remodeled as will the master bedroom. The master bedroom shows a new window being installed but the other 2 bedrooms show no alterations. The Plans Examiner knows that the windows in the other 2 bedrooms have a sill height of greater than 44" above the finish floor and thus do not meet current code. Can the examiner require the master bedroom window to meet egress? Yes, because is it is "new" and not a part of the "existing" dwelling. Can the examiner require the windows in the other two bedrooms to be replaced? No, because they are existing.

(September 6, 2001 Tri-County Building Code Forum)


Q:  

There are some jurisdictions in the Tri-County area that accept single user, unisex toilettes in "A" occupancy while others don't.


Background: When this issue is not resolved until building permit application time, it is very difficult to resolve in a building that has been fully designed.

A:  

Section 101.3 (Scope) incorrectly identifies Appendix Chapter 29 as being adopted. When the code was last modified, provisions of the appendix chapter were brought forward to the regular chapter eliminating the need for the appendix chapter. However, Table 29-A is adopted by reference in Section 2902.2. To be clear, only Table 29-A is adopted. That said, occupancies are required to have restrooms in the number determined by Chapter 29 and Table 29-A. Section 1108.2.2 imposes an additional requirement that an accessible, unisex toilet facility be provided where an aggregate of six or more male and female water closets are required in "A" occupancies, recognizing that in larger facilities it is likely that a disabled person might require assistance by a member of the opposite sex. In "M" occupancies, the required number of toilets may be much lower; in fact, a single-occupant unisex accessible restroom might fulfill all code requirements. Finally, in existing facilities, where it is impractical to fully comply with the code, Section 1113.3.7.1 may be invoked. This section allows one unisex facility in lieu of making existing facilities accessible. See 2904.2, which deals with the substantial alteration of existing Group A occupancies. The building official may approve substantial alterations without the installation of additional water closets only where it is structurally unfeasible to make such alterations. (September 6, 2001 Tri-County Building Code Forum)


Q:  

In a multistory rated building some jurisdictions require a "lid" on the bottom side of a private balcony while others do not.


Background: This typically occurs in a Type-V One-Hour, R-1 occupancy and multistory buildings where there are unit balconies that stack. It is generally agreed that even when using pressure treated materials, enclosing these decks on the underside will rapidly lead to deterioration in our moist climate. Venting these areas on the horizontal surface is not permitted in the code. Face vents are problematic. This issue regards conventional construction and not the use of heavy timber. It also deals specifically with private balconies, not exterior exit balconies.

A:  

Section 705 (Projections) speaks to architectural appendages beyond the floor area and thus applies to exterior balconies. Projections from Type-V construction may be of combustible or noncombustible construction. These projections are only required to be protected with one-hour fire resistive construction where openings are required to be protected or where they are prohibited. Therefore, balconies (other than exterior exit balconies) can be of unprotected construction. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do older buildings require seismic upgrading?
A:  

Portland has an ordinance requiring the seismic upgrading of un-reinforced masonry buildings that the City has specifically listed. Nothing in the code mandates such upgrades, but the code does give guidance about providing the upgrades. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Can a uniform commercial re-roofing permit and procedure be developed for tri-county area?
A:  

Mr. Watts with Associated Roofing Contractors posed this question. He represents commercial roofing companies in the tri-county region. The roofing association would like consistency and a uniform approach to handling re-roofing projects in the tri-county area. Mr. Watts mentioned some jurisdictions require engineering reports and some do not and noted that consistency also varies among jurisdictions regarding pre-inspections.

The panel forwarded this issue to the Tri-County Processes and Forms committee for discussion and action. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   What occupancy classification should be assigned to a dining/drinking establishment that contains more than one room each with an occupant load of 49 or less but with a total combined occupant load exceeding 50 and with room having one code compliant exit? Are there any restrictions on how large the openings between rooms can be? (See attatched diagram) Occupancy Classification

Code Reference: Section 302.1.1 defines an A-3 Occupancy as: "A building or portion of a building having an assembly room (emphasis added) with an occupant load of less than 300 without a legitimate stage, including such spaces used for educational purposes and not classified as Group B or E Occupancies."

Section 304.1 defines B Occupancies as: "Group B Occupancies shall include buildings, structures, or portions thereof, for office, professional or service type transactions, …, and eating and drinking establishments (emphasis added) with an occupant load of less than 50."

Table 10-A item 4 lists dining rooms and drinking establishments as less concentrated assembly areas using an occupant load factor of one person per 15 square feet and requires two exits when the occupant load is at least 50 persons.

A:  

Given the information submitted to the forum, the majority of the group felt the appropriate occupancy group is A-3, based on occupants' ability to migrate from space to space. It is important to note, however, that Section 301 assigns responsibility to the Building Official to classify a space or group of spaces, when the use isn't clear. The code panel members agreed that more information was needed to properly consider this question. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   In the Tri-County Checklist Section 5.0, items 5.20, 6.20, and 7.20 require structural calculations for vertical loads for equipment weighing more than400 pounds. Wouldn't any load beyond what was factored into the original design on the manufactured roof require an engineered design? If not, who would be liable for the added loading? If it is determined that all loads on manufactured roofs require engineered designs, shouldn't the Tri-County Checklist be revised so that applicants don't have to find out at the permit counter that they need an engineer for a 200-pound roof-top unit?
A:  

See OSSC, Volume 2, Section 1632.1. The 400 pound designation identified in this section refers only to seismic bracing. The structure must be capable of supporting the imposed gravity loads, and it may be necessary to provide a design proving that The code panel sent a revision request to the Tri-county Processes and Forms Committee (?) for review and action. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For plans with engineered lateral-load-resisting elements, how should we apply the use of "drag struts" or "collectors" to load-resisting elements such as shear walls or frames?
A:  

Plans with non-prescriptive (engineered) lateral-load-resisting elements must show sufficient load-transfer mechanism detail to provide a continuous load path. This may include drag struts, collectors, and blocking and strapping at re-entrant corners. (Tri-County Commercial Structural Building Code Forum, March 21, 2002


Q:   Section 1003.3.3.6 states: "Handrails shall be continuous the full length of the stairs..." Does that mean if there are landings within the flight of stairs that the handrail(s) shall be required to continue through the length of the landings?
A:  

No. Section 1003.3.3.1 stipulates that stairway includes stairs, landings, handrails and guardrails. All of these four components constitute a stairway. Section 1003.3.3.6 requires the handrails to be continuous for the full length of the stairs, not the stairway. With each intervening landing, you start new stairs. The handrail must still terminate properly and meet the other requirements of Section 1003.3.3.6. (Tri-County Building Code Forum, December 17, 2001)


Q:  

Can an exterior deck or balcony that is only accessed through an individual dwelling or guest unit in an Group R Division 1 Occupancy be considered as "within individual dwelling units" and therefore require only a 36 inch high guardrail?

 

Background: This question regards exterior deck or balcony guardrails for individual R-1 Occupancies. Section 509.2 of the OSSC states: "The top of guardrails shall not be less than 42 inches (1067 mm) in height. However, exception # 1 states: The top of guardrails for Group R, Division 3 and Group U, Division 1 Occupancies, and interior guardrails within individual dwelling units, Group R Division 3 congregate residences and guest rooms of Group R, Division 1 Occupancies may be 36 inches.

A:  

No. The code section referenced answers the question. The guardrail is not within the dwelling unit. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a one-hour rated wood frame floor-ceiling or roof-ceiling assemblies some jurisdictions require fire taping of the second (exposed) layer of gyp board while others do not.

Background: This question assumes that the gypsum board will be concealed either by surface applied materials or a suspended non-rated ceiling. It also assumes that the joints between the layers of gypsum board are staggered.
A:  

The builder needs to install per the approved assembly as prescribed by the approving agency. There may be several assemblies that are approved which can and do differ in their specific requirements. Build it as prescribed. (September 6, 2001 Tri-County Building Code Forum)


Q:   Is it the intent of the OSSC section 904.2.9 to sprinkler new apartments / condominiums three or more stories in height, even if the first floor contains a parking garage (U-1) that has the properly installed occupancy separations?
A:  

Yes. In the code, the definition of an apartment house is any building or portion thereof that contains three or more dwelling units. For the purpose of this code, that includes residential condominiums. Note that this definition refers to buildings that contain dwelling units. It does not exclude portions of the building other than dwelling units. Therefore, mixed occupancy buildings that are three or more stories in height which meet the definition of apartment house must be provided with an automatic sprinkler system throughout the entire structure. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a multistory wood-frame building some jurisdictions require one layer of 5/8 type X gypsum wallboard on the bottom of TJI joists, while others require two layers.
Background: This question concerns one-hour rated floor ceiling assemblies using pre-manufactured wood I-Joists. The assumption is that other elements of the assembly are followed. It also pertains to the lighter wood I joists rather than the TJI 55 series which has a NER tested assembly that permits a single layer outright. One key to this issue is the exchange of RC-1 channels and furring channels in the various assemblies.
A:  

Gypsum wallboard details, like the fire stopping details, need to be reviewed and agreed upon in advance. They are determined by the criteria found in the Gypsum Association manual Fire Resistance Design Manual and other approved sources such as Underwriter's Labs etc. In Tri-County, such details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the product, and to have it reviewed and approved, nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:  

Some jurisdictions allow fire-stopping methodology to be resolved in the field with a pre-installation meeting involving the affected parties. Other jurisdictions require fire-stopping details to be shown on the construction documents.


Background: The question here is not whether fire-stopping is required or not. Nor is it one that the general parameters for fire-stopping should not be laid out in the construction documents. Some jurisdictions however recognize that specifications and details may not reflect actual job conditions nor will they necessarily be drawn around the particular supplier of the fire-stop material.

A:  

Fire-stopping details need to be reviewed and agreed upon in advance, and must follow the manufacturer's instructions. In Tri-County, fire-stopping details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the appropriate product and to have it reviewed and approved nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do the sprinkler substitutions allowed in OSSC Section 508 allow the minimum one hour fire resistive protection mandates of OSSC 704.4 (requires members carrying masonry or concrete walls in buildings over one story in height to be a minimum of one hour fire-resistive construction or the fire-resistive requirements of the wall) to be waived as well?
A:  

No. 508 is a general requirement. 704.4 is a specific requirement and even applies to a non-rated building. Therefore you have to provide the one-hour protection or the fire-resistive requirement of the wall, whichever is greater. (Tri-County Building Code Forum, December 17, 2001)


Q:   For multifamily Type V - 1-HR building, do the interior closet walls need to be 1-hr construction? How about bathroom doors, closet doors, cabinets, etc.?
A:  

No. As long as you comply with Section 601.5.2.2 Hotels & Apartments, which states: "Interior nonbearing partitions within individual dwelling units in apartment houses and guestrooms or suites in hotels when such dwelling units guest rooms or suites are separated from each other and from corridors by not less than one-hour-fire-resistive construction may be constructed of: (2) Combustible framing with noncombustible materials applied to the framing in buildings of Type III or V construction.

As for bathroom doors, closet doors, cabinets etc. Section 601.5.5 Trim, states: "…Unprotected wood doors and windows may be used except where openings are required to be fire protected." (Tri-County Building Code Forum, December 17, 2001)


Q:   There are inconsistent code requirements for ventilation fans in row house construction. Every jurisdiction requires an under house fan, but some jurisdictions have required a squirrel fan, and some only require a normal bath fan. There should be a consistent requirement for the type and style of fan. Referred from the October 4, 2001 One and Two Family Code Forum.
A:  

Any fan applicable to the conditions will work-as long it meets the building code CFM rating. (Tri-County Building Code Forum, December 17, 2001)


Q:   Sometimes there are multiple permits for one job. When one permit is phoned in for an inspection, the inspectors take out all the permits and perform inspections on permits for which no inspection was requested in addition to the one which was requested. Staff is concerned that the other permits will not be inspected and that the contractor will cover the work. Is this appropriate? Should not all permits be phoned in separately for inspection?
A:  

No, it is not appropriate for inspectors to perform inspections on permits for which no inspection was requested. Yes, all permits should be phoned in separately for inspection; it is not up to the inspector to determine when the work is done; this is the responsibility of the contractor. When a contractor covers work that should be inspected it is a compliance issue that should be dealt with separately. (June 19 Tri-County Electrical Code Forum)


Q:   When is standby power required for egress illumination?
A:  

See 1003.2.9.2, "Power supply." (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   If the intent of the code is to provide the most direct egress for occupants, when is an enclosed vertical exit beneficial?
A:  

When such access serves three or more floors. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:  

Are these requirements applicable to an exterior door opening into a breezeway as described below:

 

Description - A three-story R-1 occupancy with stairways that provide egress from individual dwelling units to the public way or yard. The stairway is approximately 8 feet wide and 60 feet long with both ends fully open to the yard. The stairway is classified as interior because it does not meet UBC 1006.3.3.1 requirements for an exterior stairway.

UBC 1005.3.3, Exit Enclosures, requires interior stairways to be enclosed according to UBC 1005.3.3.3. The exterior openings may be unprotected where permitted by Table 5-A. In this case, unprotected exterior openings area allowed by Table 5-A and then only the walls separating the dwelling units from the exit are required to be fire rated.

UBC 1005.3.3.5, Openings and Penetrations, requires that the doors meet temperature-rise limitations: "All interior exit doors in an exit enclosure shall be protected by a fire assembly having a fire-protection rating of not less than one hour where one-hour-enclosure construction is permitted in Section 1005.3.3.2 and one and one-half hours where two-hour-enclosure construction is required by Section 1005.3.3.2. Such doors shall be maintained self-closing or shall be automatic closing by actuation of a smoke detector as specified in Section 713.2. All hold-open devices shall be listed for the intended purpose and shall close or release the fire assembly to the closed position in the event of a power failure. The maximum transmitted temperature end point for such doors shall not exceed 450? F (232?C) above ambient at the end of 30 minutes of the fire exposure specified in UBC Standard 7-2.

A:  

The temperature - rise limitation is required only for doors in an exit enclosure - not doors in a corridor. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Some jurisdictions waive the drinking fountain requirement in certain occupancies while others don't.

Background: This issue is primarily limited to occupancies in conjunction with R-1 occupancies. Another contributing factor is the availability of alternate sources of liquid. These alternate sources could be beverage bar, as our office has found in senior facilities or motels with continental breakfast.
A:  

A drinking fountain is required to be provided in an "A" and "E" occupancy on each floor level at an approved location (OSSC 2903.2). The only exception is "IN" a drinking or dining establishment. If there exists a conference area with a lobby/foyer, a drinking fountain shall be installed to serve the conference area. A drinking fountain is not required in the drinking or dining establishment portion of the "A" occupancy. Portable facilities or temporary facilities, such as water coolers or bottled water dispensers are not acceptable as alternatives as they can be easily removed or discontinued. Continental breakfast bars and juice bars, which may or may not be open to the public all day, do not qualify as eating or drinking establishments; thus they do not eliminate the requirement for a drinking fountain. (September 6, 2001 Tri-County Building Code Forum)


Q:   A corridor is part of an exit system, and is fully enclosed by walls, floor, ceiling, and protected openings according to UBC 1004.3.4.3. What is the difference between UBC 1004.3.4, Corridors, and 1005.3.3, Exit Enclosures?
A:  

A corridor is a portion of the exit access that leads occupants of a building to an exit. Though the term "corridor" is not defined in the code, it may be helpful to think of a corridor as being similar to a hallway: it provides access to various portions of a building and also provides access to the exterior. In multi-story buildings, corridors typically lead occupants to a stairway that leads to the ground floor. When this stairway serves three or more floors, Section 1005.3.3 requires the stairway to be located in a fire-rated enclosure called an "exit enclosure". The fire rating for the enclosure varies, depending on the type of construction and other factors. All openings leading into the exit enclosure must be fire-rated as well. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   UBC 1004.3.4. Corridors: Under what conditions does a corridor as defined in UBC 1004.3.4 become an exit enclosure as defined in UBC 1005.3.3? JSS: why does the question start with a ref to 1004.3.4, but that is not what the question refers to? Typo.
A:  

Corridors and exit enclosures are independent systems. A corridor becomes an exit enclosure when the corridor leads into or ends at a stair tower required to be an exit enclosure. UBC 1005.3.3. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Please provide the definition of attic space as it pertains to a panelized roof structure and insulation/holder assembly.
A:  

This question was referred to the State Building Codes Division for interpretation. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Are the UBC 1005.3.3.5 requirements for temperature-rise-limited doors applicable to an exterior door that exits into a corridor open to the exterior at both ends? For example, a door on an exterior wall but within a breezeway..
A:  

No, not when the door exits into a corridor; however, the requirements apply when the door exits into a stair enclosure. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   If an exit meets the requirements of a corridor as defined in UBC 1004.3.4, does it also need to meet the requirements of an exit enclosure as defined in UBC 1005.3.3.5?
A:  

No, the two satisfy different requirements. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Can a corridor include stairs that are otherwise not required to be enclosed?
A:  

Yes. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Fire Dampers in non-rated ceilings. We are installing new furnaces and new ductwork into a church where none of the ceilings are fire rated. They should be fire rated but the church is over 50 years old. In most jurisdictions, because the ceiling is not rated, we would not have to put fire dampers in the registers that penetrate the ceiling because it would not add any protection-a fire would just burn around the dampers. One jurisdiction is requiring us to put in fire dampers, reasoning that the ceiling should be fire rated and so we have to put them in based on what it should be. This does not seem consistent with other jurisdictions. We also recently did a job in a jurisdiction in which we did not need to install fire dampers or even smoke/fire dampers in the hallways because the building already had a sprinkler system. Yet a half-mile away-in another jurisdiction, the Fire Marshall-in an inspection of a church, required that the church add fire dampers (not smoke/fire dampers) to all of the hallway ceiling registers. What is right? Referred from the August 9, 2001 Mechanical Code Forum.
A:  

When a fire-rated construction is penetrated, fire dampers are required. If the construction is not fire rated (as per 713.11 & 711.4) fire dampers are not necessary. In cases like these where the ceilings were not rated, smoke/fire dampers should not have been required. In these cases, the Plans Examiner required fire dampers because the existing 50-year-old ceiling should be fire-rated by today's standards. It is important to note that we cannot base code requirements on our wishes or what we feel "should be." (September 6, 2001 Tri-County Building Code Forum)


Q:   Our department would classify a 14,000-square-foot building that houses a city or county library A-3, however, some architects say that such buildings in the tri-county area have been classified B with some accessory A uses. What is the correct classification?
A:  

Typically, libraries are "B" occupancies. But many contemporary libraries are designed for multiple uses beyond the traditional book lending and study areas to community meeting rooms and even city council chambers. In such cases, other occupancies may apply. The code panel strongly recommends that design professionals contact the building-department jurisdiction during the conceptual phase. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Recently, there has been some discussion regarding the classification of a Library. Given 14,000 s.f. Library (City or County) I would classify this building as an A-3. However, some architect's claim that such buildings in the Portland area have been classified as a B with some accessory A uses. Could you add this as a question at the building code forum?
A:  

A-3 or A-2.1 based on occupancy. You look at the predominate use of the building for assigning a use group to the building. For incidental uses of the building, their percentage of the whole area need to be determined. If the accessory /incidental use is less than 25 percent then the predominant use of the building is the main use. When you have an area where people are assembling, which in the case of a library is true, you have to classify it under Assembly use group. (Tri-County Building Code Forum, December 17, 2001)

 

The following Q and A is a reconsideration of a previous code forum answer on the subject


Q:   Should a building department accept drawings prepared by an engineer or architect but not stamped by them? In other words, is an engineer or architect required to stamp final documents when the building is exempt from the Architect's Law? How many sets of documents must carry a "wet signature"?
A:  

OAR 806-010-0045. No. An Oregon registered architect is required to stamp and sign all his or her work in this state regardless of its exemption status. Only one set of submittal documents must bear the wet signature of the architect or engineer. It is permissible for the professional stamp or seal to be electronically duplicated. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   Are the parking provisions of OSSC 1104 retroactive?
A:  

No. You must still comply with Federal ADA requirements. These requirements were retroactive in OSSC till October 1, 1996 as can be seen from the language in Section 3101(e) of the 1993 OSSC which, states "Except as required in Section 3104 for accessible parking, this code is not retroactive…". When the 1996 OSSC was adopted effective October 1, 1996, the retroactive code requirement for accessible parking were dropped from the OSSC. (Tri-County Building Code Forum, December 17, 2001)


Q:   How does Chapter 13 relate to a new packaged A/C installation on an existing building?  Specifically, is the minimum EER rating 12.5 or 10.9? The footnotes to Table 13-N on page 140.36 of the 4/1/04 version of Chapter13 refer to "New Construction" and "replacements."  It is not clear which category would apply in our case.  This is not a replacement but a new system, including all new ducts, to be installed in an existing building. This unit will provide additional cooling and ventilation for an existing tenant space and serve a newly created tenant space within an existing building.
A:   Use the calculation for new construction. (Tri-County Code Forum, December 2004)
Q:   The IBC, 502.1 defines Building Area as "The area included within surrounding exterior walls..." In calculating the allowable area, is the area of the exterior walls to be included, or just the interior area exclusive of the exterior walls?
A:  

For the purposes of calculating the allowable area in OSSC section 503, the IBC Commentary says that the allowable area is the inside face of the exterior wall. However, the panel refers this question to the state for interpretation: www.bcd.oregon.gov/programs/structural/interps/OSSC_Interp_503_area_of_building.pdf 
(Tri-County Code Forum June 2005)


Q:   Will the text given in 302.2.1, which states that assembly spaces that are accessory uses to Group E are not required to be considered separate occupancies be interpreted in Tri-County to mean that there is no occupancy separation required?  Table 302.3.2 indicates separation is required (2-Hour) which seems to be in conflict with 302.2.1. The spaces we are curious about typically include gymnasiums, school cafeteria, and possibly school library.
A:   The code section refers to assembly occupancies that are accessory to Group E, in which case they are not required to be separated. If, by chance, there was an A occupancy adjacent to the E, but under separate control, then they would need the appropriate occupancy separation. (Tri-County Code Forum, September 2004)
Q:   Paragraph 303.1 states that assembly spaces which are accessory to Group E in accordance with 302.2 are not considered assembly occupancies. Will that be the case for K-12 public school buildings in Tri-County? If yes, are these uses classified as E for the purposes of determining occupant load, egress width, etc.?
A:   Section 302.3.1 states that for non-separated uses, all other code requirements shall apply to each portion of the building based on the use of that space. The exiting requirements for the assembly portions of the building need to meet the requirements based on that use. (Tri-County Code Forum, September 2004)
Q:   Please clarify the definition of atrium per 404.1.1 as it relates to an opening in a two-story building.
A:  

The definition in the 2004 OSSC of what constitutes an "atrium" is nearly identical to that found in section 202 of the 1998 OSSC. However, the  companion provisions for "shafts" and "vertical exit enclosures" in the respective code editions have changed considerably.

 

For example, section 711.3 of the 1998 OSSC stated that; "In other than Group I Occupancies, openings that penetrate only one floor and are not connected with openings communicating with other stories or basements and that are not concealed within building construction assemblies need not be enclosed." As such, most required stairways were permitted to atmospherically connect two floors.

 

In contrast, section 707.2, exception 7.2 of the 2004 OSSC will not allow the "required means of egress system" to be unenclosed  between floors except as permitted in section 1019.1. A cursory look at section 1019.1 reveals that the required stairways in the means of egress must be enclosed except for the following circumstances:

 

In other than Group H and I occupancies, a stairway serving an occupant load of less than 10 not more than one story above the level of exit discharge.

In other than occupancy Groups H and I, a maximum of 50 percent of egress stairways serving one adjacent floor are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Any two such interconnected floors shall not be open to other floors.

 

In other than occupancy Groups H and I, interior egress stairways serving only the first and second stories of a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Such interconnected stories shall not be open to other stories.

 

In short, where a sprinkler system is installed, stairways serving the first and second stories may be unenclosed. In unsprinklered buildings, 50 percent of the egress stairways and stairways serving 10 or less persons above the level of exit discharge may be unenclosed.

 

As noted, this is only one example of the differences. Sections 404, 707.2 and 1019.1 contain additional exceptions that warrant further examination and application. (Tri-County Code Forum, March 2005)
Q:   For purposes of applying the requirements for natural light, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural light from the living/dining area?
A:   Yes, if it meets the qualifications of the opening described in Section 1205.2.1. of the 2004 0SSC. (Tri-County Code Forum, September 2004)
Q:   Assuming the "den" is not provided with mechanical ventilation, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural ventilation from the living/dining area?
A:   Yes, if the opening meets the minimum opening requirements of Section 1203.4.1.1 of the 2004 OSSC . (Tri-County Code Forum, September 2004)
Q:  

1-4. Code References: 

Section 310.4  Basements in dwelling units and every sleeping room below the fourth story shall have at least one operable window or door approved for emergency escape or rescue that shall open directly to a public street, public alley, yard or exit court.

 

Section 1204.2  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural light by means of exterior glazed openings with an area not less than one tenth the floor area of such rooms with a minimum of 10 square feet.


Section 1204.3  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural ventillation as specified in section 1203.2.4 or by a mechanical ventilation system which shall be capable of supplying ventilation air in accordance with Table 12-A.

 

Section 1204.1  For the purpose of determining the light or ventilation and source control ventilation for Group R Occupancies required by this section and Table 12-A, any room may be considered as a portion of an adjoining room when one half of the area of the common wall is open and unobstructed and provides an opening of not less that one tenth of the floor area of the interior room or 25 square feet, whichever is greater.

 

The floor plans for dwelling units each have an interior room labeled as a "den." In one unit the "den" has a clothes closet. The "den" in the other unit does not have a closet. Assuming these units are not in a building complying with the requirements of chapter 4 for a high rise building, please respond to the following questions:

 

Is the "den" containing the clothes closet considered a sleeping room for purposes of applying emergency egress requirements?  Is the "den" that does not contain a closet considered a sleeping room for purposes of applying emergency egress requirements?

A:   The applicant is required to label the rooms accurately. If the room has a closet and is labeled "den," building departments should accept the designation and make no assumption that it will be used other than how it is labeled. For example, many living rooms have closets but are not treated as sleeping rooms. (Tri-County Code Forum, September 2004)
Q:   We have a clarification request for the next Building Code Forum.  One of our colleagues recently found the following: Under section 105.2 Exceptions 13 (Agricultural Structures) and 14 ( Equine Facilities), the new code refers to ORS 455.310. ORS 455.310 covers exempt residential construction, not agricultural structures. ORS 455.315 covers exempt agricultural structures. See ORS index at http://www.leg.state.or.us/ors/455.html You may want to point this out so that it is addressed in future issuances of the Code.
A:   The wrong statute was cited in the code and will be corrected. (Tri-County Code Forum, March 2005)
Q:   What are the new OSSC requirements for firewalls in apartments?
A:   The new code requires the dwelling unit separation to be one hour, unless the building is sprinkled; then unit separation can be 30 minutes. See also section 708. (Tri-County Code Forum, June 2005)
Q:   Is there a definition for a 30-minute wall?
A:   Table 721.6.2 of the OSSC  assigns a fire-resistive time period to various wall components. Using this table, a designer is able to establish an overall fire-resistive time period for a given assembly by adding up the times assigned to interior and exterior membranes, the wood frame and the addition of certain insulations (unique to wood frame construction). (Tri-County Code Forum, June 2005)
Q:   If the 2-1/2 inch net section is still required by the 2004 Structural Specialty Code, does the minimum net section apply to metal plate connected pre-engineered roof trusses used to anchor masonry or concrete walls?
A:   The prescriptive provisions have been replaced with design provisions. (Tri-County Code Forum, June 2005)
Q:   For ADA access, the code requires 12 inches adjacent to the ?push? side of a door equipped with a closer and a latch. If the latch is panic hardware, is the 12 inches of adjacent space still required?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   When there are several properties under the same ownership how do you treat property lines?
A:   Contact your local jurisdiction. The answer depends on which jurisdiction you?re in and must be judged on a case by case basis. Suggestions from the panel included the use of a covenant (not to sell separately) or a lot line adjustment. (Tri-County Code Forum, September 2004)
Q:  

Are there situations in which an accessible table located adjacent to a bar counter can be provided instead of a 60-inch long portion of the bar counter lowered to 34 inches?

Bar counters in restaurants and lounges are usually 36 to 44 inches high where patrons sit on raised seats. Ice and drink dispensers, coolers, sinks, and other equipment are typically built into the barkeep side of the casework. It is common for small restaurants to propose a 6 to 8 foot long bar.

 

Section 1108.4.5 completely eliminates raised bar counters that are 5 feet long or less. Bar counters less than 10 feet long are impractical because the remaining raised portion is less than 5 feet long. The end result is the restaurant does not have a raised bar, which seems overly restrictive.

 

Note that The Americans with Disabilities Act Accessibility Guidelines (ADAAG) Section 5.2 allows bar service to be provided at accessible tables within the same area as the raised counter.

A:  

Section 1101.6 references ORS 447.250 and allows waivers or modifications if the code section is more restrictive than ADA guidelines or the Fair Housing Act. If the new ADAAG guidelines allow this alternate method, the applicant may be able to appeal to the state. It could also be approved at the local level as an alternate method, but jurisdictions may be hesitant to make this approval without guidance from the state.

 

It would seem that if a table is assigned for use as an "accessible table" and is made available for use when needed that it could fulfill the requirement. However, if the table was in use and was then needed, it could create a slight inconvenience as the current patrons would have to be relocated to make room for the physically challenged user. (Tri-County Code Forum, September 2004)


Q:   Our current project is the restoration of a fire-damaged school. Would this work be considered a "repair," an "addition," or an "alteration"? While most of the project consists of rebuilding the classrooms and does not include adding any new space, the original structure is more than 65 years old and could use some structural updates, as well as the addition of an smoke alarm system. Would such additions change the category of construction?
A:   The work to restore the fire-damaged area would be considered a repair, even if new trusses must be added to be sufficient to carry the load. The fire code  has a retroactive provision that requires smoke alarms in all such buildings. Work with your local building official to discuss details. (Tri-County Code Forum, June 2005)
Q:   Do S2 parking structures need to be sprinklered?
A:   406.4 and 903.2.9 Open, no; enclosed, yes. (Tri-County Code Forum, June 2005)
Q:   Does the shape of the ceiling tiles, whether they are flat or regular, have a  bearing on the grid requirements?
A:   No. (Tri-County Code Forum, June 2005)
Q:   Can tiles be scribed in at all sides and not affect the deflection of the grid?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   If a ceiling grid system has no tiles or lights directly attached to the grid, does it then become an aesthetic system and not need to meet any of the ceiling grid code requirements?
A:   Any such grid system must meet the structural code requirements. (Tri-County Code Forum, June 2005)
Q:   Please clarify 1621 and referenced ASCE 9.6.2.6.2.2 as it relates to suspended ceiling tile and sprinkler head design.
A:   The panel refers this question to the Building Codes Division for interpretation. It appears that it is extremely difficult for builders to locate sprinklers or seismic joints that are the correct size. (Tri-County Code Forum, March 2005)
Q:   What is the requirement for upper cabinet height?
A:  

UFAS (Kitchen storage) states that " Max. height shall be 48inches for at least one shelf of all cabinets & storage shelves mounted above work counters.? Does that mean one shelf of EACH upper cabinet? Or does that mean just one shelf is required to be mounted at 48 inches and the others can be mounted higher?


UFAS is not the adopted accessibility standard in the State of Oregon. However,  OSSC 1109.11.2, which is based on the Americans with Disabilities Act Architectural Guidelines (ADAAG), requires 50 percent of the cabinets to have at least one shelf within the height limitation. (Tri-County Code Forum, June 2005)


Q:   I have a question for further clarification on a ventilation question related to the Q&A posed during the April 8 forum and answered in the August-October 2004 News Site, specifically Oregon Structural Specialty Code, Section 1505. Can alternate ventilation (gable end vents or extra vents in non-vaulted areas) be installed to compensate for any blocked or restricted soffit vents, due to insulation filled rafter or scissor truss cavities, and achieve a 150:1 venting requirement? Any 2x6, 2x8, 2x10 rafter, for a vaulted ceiling, is simply too small to allow for R-30 Fiberglass Batt insulation and allow 1" air gap. (R-30= 9-1/4(one quarter)" for high density fiberglass insulation, 2x10 =9-1/4(one quarter)"   there is no room for air gap) Any scissor truss is only 3-1/2(one half)" at the soffit vent, and there is no possible way to achieve either R-30 or the required air gap for the first 18" to 36" of the scissor truss cavity (depending upon pitches) There is a conflict between structural codes allowing 2x4 trusses, 2x6, 2x8 and 2x10 rafters, the insulation requirements and ventilation requirements. The insulation gets crammed into rafter spaces and venting is blocked off. When scissor trusses or less than 2x12 rafters are used, the plans examiner should be able to know that mathematically the soffit vents will be blocked. Shouldn't this be the step when alternate venting should be called out? How do we meet all three requirements? We have had call-back on houses that "meet codes" and were signed off, but now have high moisture build-up in the attic and mold growth on the roof sheeting. Obviously the current venting is not working!
A:   The code allows for the compression of roof insulation in sloped roof assemblies in proximity to eave vents. The code also requires the installation of "baffles" in order to maintain cross ventilation. (Tri-County Code Forum, December 2004)
Q:   Please clarify the definition of "walls directly attached to structure."  Do walls that are braced to the structure meet his requirement?
A:   If the wall is bracing a building, or it is relying on the building for its support, it is a part of the structure. (Tri-County Code Forum, June 2005)
Q:   What if you re-stripe?
A:  

If you're repainting the existing stripes in an existing lot over the existing stripes, that is fine, the repainting of the stripe can be to match existing stripes. If you want to move spaces or change the configuration, you can do so as long as you comply with the code in existence at the time of reconfiguring the parking lot. (Tri-County Building Code Forum, December 17, 2001)


Q:   The 1998 Structural Specialty Code based on the 1997 UBC Section 1633.2.8.1. Item 5 requires that wood elements of a concrete or masonry wall anchorage system "have a minimum actual net thickness of 2 1/2 inches."  Does the current 2004 Structural Specialty Code based on the 2003 IBC have an equivalent requirement?  If yes, where is the citation requiring 2-1/2 inch (3x)wood elements for the anchorage of concrete or masonry wall systems?
A:   No. There is nothing in the current code that addresses this issue. (Tri-County Code Forum, June 2005)

Administration

Q:   There is widespread inconsistency in accessibility requirements. Some jurisdictions have issued accessibility interpretations while others don't even review accessibility details in the documents saying that this is a federal civil law.
A:  

The Building Official, by ORS 447, is responsible to enforce these provisions (Chapter 11) of the code. Therefore all jurisdictions should provide accessibility guidelines for plan review and provide comments to the applicant during the plan review process. Beginning Sept. 1, Tri-County jurisdictions are required to use the commercial application checklist and process. This process provides the opportunity for a pre-submittal meeting during which the jurisdiction can outline the accessibility requirements of the project, using the commercial application checklist as a guide.(September 6, 2001 Tri-County Building Code Forum)


Q:   Is it permissible to compare only base shear values for wind and earthquake loads to decide whether wind or seismic loads govern the design?
A:  

No, it is not permissible. A correct analysis requires determining both the earthquake loads and the wind loads on an element of a structure. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For an existing building being relocated with no interior remodel or change of use, what are the upgrade requirements by code?
A:  

Section 3404 of the OSSC addresses "moved buildings" as does ORS 455.410 entitled "Relocated Buildings; Substantial Compliance Required; Permits." The statute states that "existing buildings or structures which are removed from their foundation and relocated to another site within this state shall be in substantial compliance in accordance to the statute." In short, the statute recognizes moved buildings as existing structures. This statute defines "substantial compliance" and addresses upgrade requirements in terms of foundation construction, installation upgrades, smoke detection and permit requirements. The statute requires the new foundation to fully comply with current building codes. It also requires the ceiling and underfloor insulation to be upgraded to current levels. It requires the installation of smoke alarms at all locations the code imposes for new construction, but only requires the alarms to be hardwired and interconnected when wall and ceiling finishes have been removed, much like we see with residential alterations. The jurisdiction cannot require existing windows (or other elements) to be upgraded for reasons of energy code compliance or to meet egress requirements. The only time a jurisdiction can require upgrades is in the case where the moved structure is altered and then only those portions that are altered must be upgraded. For example, let's say an existing 3-bedroom dwelling is relocated to a new site. The plans show that the kitchen will be remodeled as will the master bedroom. The master bedroom shows a new window being installed but the other 2 bedrooms show no alterations. The Plans Examiner knows that the windows in the other 2 bedrooms have a sill height of greater than 44" above the finish floor and thus do not meet current code. Can the examiner require the master bedroom window to meet egress? Yes, because is it is "new" and not a part of the "existing" dwelling. Can the examiner require the windows in the other two bedrooms to be replaced? No, because they are existing.

(September 6, 2001 Tri-County Building Code Forum)


Q:  

There are some jurisdictions in the Tri-County area that accept single user, unisex toilettes in "A" occupancy while others don't.


Background: When this issue is not resolved until building permit application time, it is very difficult to resolve in a building that has been fully designed.

A:  

Section 101.3 (Scope) incorrectly identifies Appendix Chapter 29 as being adopted. When the code was last modified, provisions of the appendix chapter were brought forward to the regular chapter eliminating the need for the appendix chapter. However, Table 29-A is adopted by reference in Section 2902.2. To be clear, only Table 29-A is adopted. That said, occupancies are required to have restrooms in the number determined by Chapter 29 and Table 29-A. Section 1108.2.2 imposes an additional requirement that an accessible, unisex toilet facility be provided where an aggregate of six or more male and female water closets are required in "A" occupancies, recognizing that in larger facilities it is likely that a disabled person might require assistance by a member of the opposite sex. In "M" occupancies, the required number of toilets may be much lower; in fact, a single-occupant unisex accessible restroom might fulfill all code requirements. Finally, in existing facilities, where it is impractical to fully comply with the code, Section 1113.3.7.1 may be invoked. This section allows one unisex facility in lieu of making existing facilities accessible. See 2904.2, which deals with the substantial alteration of existing Group A occupancies. The building official may approve substantial alterations without the installation of additional water closets only where it is structurally unfeasible to make such alterations. (September 6, 2001 Tri-County Building Code Forum)


Q:  

In a multistory rated building some jurisdictions require a "lid" on the bottom side of a private balcony while others do not.


Background: This typically occurs in a Type-V One-Hour, R-1 occupancy and multistory buildings where there are unit balconies that stack. It is generally agreed that even when using pressure treated materials, enclosing these decks on the underside will rapidly lead to deterioration in our moist climate. Venting these areas on the horizontal surface is not permitted in the code. Face vents are problematic. This issue regards conventional construction and not the use of heavy timber. It also deals specifically with private balconies, not exterior exit balconies.

A:  

Section 705 (Projections) speaks to architectural appendages beyond the floor area and thus applies to exterior balconies. Projections from Type-V construction may be of combustible or noncombustible construction. These projections are only required to be protected with one-hour fire resistive construction where openings are required to be protected or where they are prohibited. Therefore, balconies (other than exterior exit balconies) can be of unprotected construction. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do older buildings require seismic upgrading?
A:  

Portland has an ordinance requiring the seismic upgrading of un-reinforced masonry buildings that the City has specifically listed. Nothing in the code mandates such upgrades, but the code does give guidance about providing the upgrades. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Can a uniform commercial re-roofing permit and procedure be developed for tri-county area?
A:  

Mr. Watts with Associated Roofing Contractors posed this question. He represents commercial roofing companies in the tri-county region. The roofing association would like consistency and a uniform approach to handling re-roofing projects in the tri-county area. Mr. Watts mentioned some jurisdictions require engineering reports and some do not and noted that consistency also varies among jurisdictions regarding pre-inspections.

The panel forwarded this issue to the Tri-County Processes and Forms committee for discussion and action. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   What occupancy classification should be assigned to a dining/drinking establishment that contains more than one room each with an occupant load of 49 or less but with a total combined occupant load exceeding 50 and with room having one code compliant exit? Are there any restrictions on how large the openings between rooms can be? (See attatched diagram) Occupancy Classification

Code Reference: Section 302.1.1 defines an A-3 Occupancy as: "A building or portion of a building having an assembly room (emphasis added) with an occupant load of less than 300 without a legitimate stage, including such spaces used for educational purposes and not classified as Group B or E Occupancies."

Section 304.1 defines B Occupancies as: "Group B Occupancies shall include buildings, structures, or portions thereof, for office, professional or service type transactions, …, and eating and drinking establishments (emphasis added) with an occupant load of less than 50."

Table 10-A item 4 lists dining rooms and drinking establishments as less concentrated assembly areas using an occupant load factor of one person per 15 square feet and requires two exits when the occupant load is at least 50 persons.

A:  

Given the information submitted to the forum, the majority of the group felt the appropriate occupancy group is A-3, based on occupants' ability to migrate from space to space. It is important to note, however, that Section 301 assigns responsibility to the Building Official to classify a space or group of spaces, when the use isn't clear. The code panel members agreed that more information was needed to properly consider this question. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   In the Tri-County Checklist Section 5.0, items 5.20, 6.20, and 7.20 require structural calculations for vertical loads for equipment weighing more than400 pounds. Wouldn't any load beyond what was factored into the original design on the manufactured roof require an engineered design? If not, who would be liable for the added loading? If it is determined that all loads on manufactured roofs require engineered designs, shouldn't the Tri-County Checklist be revised so that applicants don't have to find out at the permit counter that they need an engineer for a 200-pound roof-top unit?
A:  

See OSSC, Volume 2, Section 1632.1. The 400 pound designation identified in this section refers only to seismic bracing. The structure must be capable of supporting the imposed gravity loads, and it may be necessary to provide a design proving that The code panel sent a revision request to the Tri-county Processes and Forms Committee (?) for review and action. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   For plans with engineered lateral-load-resisting elements, how should we apply the use of "drag struts" or "collectors" to load-resisting elements such as shear walls or frames?
A:  

Plans with non-prescriptive (engineered) lateral-load-resisting elements must show sufficient load-transfer mechanism detail to provide a continuous load path. This may include drag struts, collectors, and blocking and strapping at re-entrant corners. (Tri-County Commercial Structural Building Code Forum, March 21, 2002


Q:   Section 1003.3.3.6 states: "Handrails shall be continuous the full length of the stairs..." Does that mean if there are landings within the flight of stairs that the handrail(s) shall be required to continue through the length of the landings?
A:  

No. Section 1003.3.3.1 stipulates that stairway includes stairs, landings, handrails and guardrails. All of these four components constitute a stairway. Section 1003.3.3.6 requires the handrails to be continuous for the full length of the stairs, not the stairway. With each intervening landing, you start new stairs. The handrail must still terminate properly and meet the other requirements of Section 1003.3.3.6. (Tri-County Building Code Forum, December 17, 2001)


Q:  

Can an exterior deck or balcony that is only accessed through an individual dwelling or guest unit in an Group R Division 1 Occupancy be considered as "within individual dwelling units" and therefore require only a 36 inch high guardrail?

 

Background: This question regards exterior deck or balcony guardrails for individual R-1 Occupancies. Section 509.2 of the OSSC states: "The top of guardrails shall not be less than 42 inches (1067 mm) in height. However, exception # 1 states: The top of guardrails for Group R, Division 3 and Group U, Division 1 Occupancies, and interior guardrails within individual dwelling units, Group R Division 3 congregate residences and guest rooms of Group R, Division 1 Occupancies may be 36 inches.

A:  

No. The code section referenced answers the question. The guardrail is not within the dwelling unit. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a one-hour rated wood frame floor-ceiling or roof-ceiling assemblies some jurisdictions require fire taping of the second (exposed) layer of gyp board while others do not.

Background: This question assumes that the gypsum board will be concealed either by surface applied materials or a suspended non-rated ceiling. It also assumes that the joints between the layers of gypsum board are staggered.
A:  

The builder needs to install per the approved assembly as prescribed by the approving agency. There may be several assemblies that are approved which can and do differ in their specific requirements. Build it as prescribed. (September 6, 2001 Tri-County Building Code Forum)


Q:   Is it the intent of the OSSC section 904.2.9 to sprinkler new apartments / condominiums three or more stories in height, even if the first floor contains a parking garage (U-1) that has the properly installed occupancy separations?
A:  

Yes. In the code, the definition of an apartment house is any building or portion thereof that contains three or more dwelling units. For the purpose of this code, that includes residential condominiums. Note that this definition refers to buildings that contain dwelling units. It does not exclude portions of the building other than dwelling units. Therefore, mixed occupancy buildings that are three or more stories in height which meet the definition of apartment house must be provided with an automatic sprinkler system throughout the entire structure. (Tri-County Building Code Forum, December 17, 2001)


Q:   In a multistory wood-frame building some jurisdictions require one layer of 5/8 type X gypsum wallboard on the bottom of TJI joists, while others require two layers.
Background: This question concerns one-hour rated floor ceiling assemblies using pre-manufactured wood I-Joists. The assumption is that other elements of the assembly are followed. It also pertains to the lighter wood I joists rather than the TJI 55 series which has a NER tested assembly that permits a single layer outright. One key to this issue is the exchange of RC-1 channels and furring channels in the various assemblies.
A:  

Gypsum wallboard details, like the fire stopping details, need to be reviewed and agreed upon in advance. They are determined by the criteria found in the Gypsum Association manual Fire Resistance Design Manual and other approved sources such as Underwriter's Labs etc. In Tri-County, such details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the product, and to have it reviewed and approved, nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:  

Some jurisdictions allow fire-stopping methodology to be resolved in the field with a pre-installation meeting involving the affected parties. Other jurisdictions require fire-stopping details to be shown on the construction documents.


Background: The question here is not whether fire-stopping is required or not. Nor is it one that the general parameters for fire-stopping should not be laid out in the construction documents. Some jurisdictions however recognize that specifications and details may not reflect actual job conditions nor will they necessarily be drawn around the particular supplier of the fire-stop material.

A:  

Fire-stopping details need to be reviewed and agreed upon in advance, and must follow the manufacturer's instructions. In Tri-County, fire-stopping details can be a deferred submittal item. The deferred submittal process gives the architect or builder sufficient time to determine the appropriate product and to have it reviewed and approved nearer to the time of installation. (September 6, 2001 Tri-County Building Code Forum)


Q:   Do the sprinkler substitutions allowed in OSSC Section 508 allow the minimum one hour fire resistive protection mandates of OSSC 704.4 (requires members carrying masonry or concrete walls in buildings over one story in height to be a minimum of one hour fire-resistive construction or the fire-resistive requirements of the wall) to be waived as well?
A:  

No. 508 is a general requirement. 704.4 is a specific requirement and even applies to a non-rated building. Therefore you have to provide the one-hour protection or the fire-resistive requirement of the wall, whichever is greater. (Tri-County Building Code Forum, December 17, 2001)


Q:   For multifamily Type V - 1-HR building, do the interior closet walls need to be 1-hr construction? How about bathroom doors, closet doors, cabinets, etc.?
A:  

No. As long as you comply with Section 601.5.2.2 Hotels & Apartments, which states: "Interior nonbearing partitions within individual dwelling units in apartment houses and guestrooms or suites in hotels when such dwelling units guest rooms or suites are separated from each other and from corridors by not less than one-hour-fire-resistive construction may be constructed of: (2) Combustible framing with noncombustible materials applied to the framing in buildings of Type III or V construction.

As for bathroom doors, closet doors, cabinets etc. Section 601.5.5 Trim, states: "…Unprotected wood doors and windows may be used except where openings are required to be fire protected." (Tri-County Building Code Forum, December 17, 2001)


Q:   There are inconsistent code requirements for ventilation fans in row house construction. Every jurisdiction requires an under house fan, but some jurisdictions have required a squirrel fan, and some only require a normal bath fan. There should be a consistent requirement for the type and style of fan. Referred from the October 4, 2001 One and Two Family Code Forum.
A:  

Any fan applicable to the conditions will work-as long it meets the building code CFM rating. (Tri-County Building Code Forum, December 17, 2001)


Q:   Sometimes there are multiple permits for one job. When one permit is phoned in for an inspection, the inspectors take out all the permits and perform inspections on permits for which no inspection was requested in addition to the one which was requested. Staff is concerned that the other permits will not be inspected and that the contractor will cover the work. Is this appropriate? Should not all permits be phoned in separately for inspection?
A:  

No, it is not appropriate for inspectors to perform inspections on permits for which no inspection was requested. Yes, all permits should be phoned in separately for inspection; it is not up to the inspector to determine when the work is done; this is the responsibility of the contractor. When a contractor covers work that should be inspected it is a compliance issue that should be dealt with separately. (June 19 Tri-County Electrical Code Forum)


Q:   When is standby power required for egress illumination?
A:  

See 1003.2.9.2, "Power supply." (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   If the intent of the code is to provide the most direct egress for occupants, when is an enclosed vertical exit beneficial?
A:  

When such access serves three or more floors. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:  

Are these requirements applicable to an exterior door opening into a breezeway as described below:

 

Description - A three-story R-1 occupancy with stairways that provide egress from individual dwelling units to the public way or yard. The stairway is approximately 8 feet wide and 60 feet long with both ends fully open to the yard. The stairway is classified as interior because it does not meet UBC 1006.3.3.1 requirements for an exterior stairway.

UBC 1005.3.3, Exit Enclosures, requires interior stairways to be enclosed according to UBC 1005.3.3.3. The exterior openings may be unprotected where permitted by Table 5-A. In this case, unprotected exterior openings area allowed by Table 5-A and then only the walls separating the dwelling units from the exit are required to be fire rated.

UBC 1005.3.3.5, Openings and Penetrations, requires that the doors meet temperature-rise limitations: "All interior exit doors in an exit enclosure shall be protected by a fire assembly having a fire-protection rating of not less than one hour where one-hour-enclosure construction is permitted in Section 1005.3.3.2 and one and one-half hours where two-hour-enclosure construction is required by Section 1005.3.3.2. Such doors shall be maintained self-closing or shall be automatic closing by actuation of a smoke detector as specified in Section 713.2. All hold-open devices shall be listed for the intended purpose and shall close or release the fire assembly to the closed position in the event of a power failure. The maximum transmitted temperature end point for such doors shall not exceed 450? F (232?C) above ambient at the end of 30 minutes of the fire exposure specified in UBC Standard 7-2.

A:  

The temperature - rise limitation is required only for doors in an exit enclosure - not doors in a corridor. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Some jurisdictions waive the drinking fountain requirement in certain occupancies while others don't.

Background: This issue is primarily limited to occupancies in conjunction with R-1 occupancies. Another contributing factor is the availability of alternate sources of liquid. These alternate sources could be beverage bar, as our office has found in senior facilities or motels with continental breakfast.
A:  

A drinking fountain is required to be provided in an "A" and "E" occupancy on each floor level at an approved location (OSSC 2903.2). The only exception is "IN" a drinking or dining establishment. If there exists a conference area with a lobby/foyer, a drinking fountain shall be installed to serve the conference area. A drinking fountain is not required in the drinking or dining establishment portion of the "A" occupancy. Portable facilities or temporary facilities, such as water coolers or bottled water dispensers are not acceptable as alternatives as they can be easily removed or discontinued. Continental breakfast bars and juice bars, which may or may not be open to the public all day, do not qualify as eating or drinking establishments; thus they do not eliminate the requirement for a drinking fountain. (September 6, 2001 Tri-County Building Code Forum)


Q:   A corridor is part of an exit system, and is fully enclosed by walls, floor, ceiling, and protected openings according to UBC 1004.3.4.3. What is the difference between UBC 1004.3.4, Corridors, and 1005.3.3, Exit Enclosures?
A:  

A corridor is a portion of the exit access that leads occupants of a building to an exit. Though the term "corridor" is not defined in the code, it may be helpful to think of a corridor as being similar to a hallway: it provides access to various portions of a building and also provides access to the exterior. In multi-story buildings, corridors typically lead occupants to a stairway that leads to the ground floor. When this stairway serves three or more floors, Section 1005.3.3 requires the stairway to be located in a fire-rated enclosure called an "exit enclosure". The fire rating for the enclosure varies, depending on the type of construction and other factors. All openings leading into the exit enclosure must be fire-rated as well. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   UBC 1004.3.4. Corridors: Under what conditions does a corridor as defined in UBC 1004.3.4 become an exit enclosure as defined in UBC 1005.3.3? JSS: why does the question start with a ref to 1004.3.4, but that is not what the question refers to? Typo.
A:  

Corridors and exit enclosures are independent systems. A corridor becomes an exit enclosure when the corridor leads into or ends at a stair tower required to be an exit enclosure. UBC 1005.3.3. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Please provide the definition of attic space as it pertains to a panelized roof structure and insulation/holder assembly.
A:  

This question was referred to the State Building Codes Division for interpretation. (Tri-County Commercial Structural Building Code Forum, September 19, 2002)


Q:   Are the UBC 1005.3.3.5 requirements for temperature-rise-limited doors applicable to an exterior door that exits into a corridor open to the exterior at both ends? For example, a door on an exterior wall but within a breezeway..
A:  

No, not when the door exits into a corridor; however, the requirements apply when the door exits into a stair enclosure. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   If an exit meets the requirements of a corridor as defined in UBC 1004.3.4, does it also need to meet the requirements of an exit enclosure as defined in UBC 1005.3.3.5?
A:  

No, the two satisfy different requirements. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Can a corridor include stairs that are otherwise not required to be enclosed?
A:  

Yes. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Fire Dampers in non-rated ceilings. We are installing new furnaces and new ductwork into a church where none of the ceilings are fire rated. They should be fire rated but the church is over 50 years old. In most jurisdictions, because the ceiling is not rated, we would not have to put fire dampers in the registers that penetrate the ceiling because it would not add any protection-a fire would just burn around the dampers. One jurisdiction is requiring us to put in fire dampers, reasoning that the ceiling should be fire rated and so we have to put them in based on what it should be. This does not seem consistent with other jurisdictions. We also recently did a job in a jurisdiction in which we did not need to install fire dampers or even smoke/fire dampers in the hallways because the building already had a sprinkler system. Yet a half-mile away-in another jurisdiction, the Fire Marshall-in an inspection of a church, required that the church add fire dampers (not smoke/fire dampers) to all of the hallway ceiling registers. What is right? Referred from the August 9, 2001 Mechanical Code Forum.
A:  

When a fire-rated construction is penetrated, fire dampers are required. If the construction is not fire rated (as per 713.11 & 711.4) fire dampers are not necessary. In cases like these where the ceilings were not rated, smoke/fire dampers should not have been required. In these cases, the Plans Examiner required fire dampers because the existing 50-year-old ceiling should be fire-rated by today's standards. It is important to note that we cannot base code requirements on our wishes or what we feel "should be." (September 6, 2001 Tri-County Building Code Forum)


Q:   Our department would classify a 14,000-square-foot building that houses a city or county library A-3, however, some architects say that such buildings in the tri-county area have been classified B with some accessory A uses. What is the correct classification?
A:  

Typically, libraries are "B" occupancies. But many contemporary libraries are designed for multiple uses beyond the traditional book lending and study areas to community meeting rooms and even city council chambers. In such cases, other occupancies may apply. The code panel strongly recommends that design professionals contact the building-department jurisdiction during the conceptual phase. (Tri-County Commercial Structural Building Code Forum, December 5, 2002)


Q:   Recently, there has been some discussion regarding the classification of a Library. Given 14,000 s.f. Library (City or County) I would classify this building as an A-3. However, some architect's claim that such buildings in the Portland area have been classified as a B with some accessory A uses. Could you add this as a question at the building code forum?
A:  

A-3 or A-2.1 based on occupancy. You look at the predominate use of the building for assigning a use group to the building. For incidental uses of the building, their percentage of the whole area need to be determined. If the accessory /incidental use is less than 25 percent then the predominant use of the building is the main use. When you have an area where people are assembling, which in the case of a library is true, you have to classify it under Assembly use group. (Tri-County Building Code Forum, December 17, 2001)

 

The following Q and A is a reconsideration of a previous code forum answer on the subject


Q:   Should a building department accept drawings prepared by an engineer or architect but not stamped by them? In other words, is an engineer or architect required to stamp final documents when the building is exempt from the Architect's Law? How many sets of documents must carry a "wet signature"?
A:  

OAR 806-010-0045. No. An Oregon registered architect is required to stamp and sign all his or her work in this state regardless of its exemption status. Only one set of submittal documents must bear the wet signature of the architect or engineer. It is permissible for the professional stamp or seal to be electronically duplicated. (Tri-County Commercial Structural Building Code Forum, March 21, 2002)


Q:   Are the parking provisions of OSSC 1104 retroactive?
A:  

No. You must still comply with Federal ADA requirements. These requirements were retroactive in OSSC till October 1, 1996 as can be seen from the language in Section 3101(e) of the 1993 OSSC which, states "Except as required in Section 3104 for accessible parking, this code is not retroactive…". When the 1996 OSSC was adopted effective October 1, 1996, the retroactive code requirement for accessible parking were dropped from the OSSC. (Tri-County Building Code Forum, December 17, 2001)


Q:   How does Chapter 13 relate to a new packaged A/C installation on an existing building?  Specifically, is the minimum EER rating 12.5 or 10.9? The footnotes to Table 13-N on page 140.36 of the 4/1/04 version of Chapter13 refer to "New Construction" and "replacements."  It is not clear which category would apply in our case.  This is not a replacement but a new system, including all new ducts, to be installed in an existing building. This unit will provide additional cooling and ventilation for an existing tenant space and serve a newly created tenant space within an existing building.
A:   Use the calculation for new construction. (Tri-County Code Forum, December 2004)
Q:   The IBC, 502.1 defines Building Area as "The area included within surrounding exterior walls..." In calculating the allowable area, is the area of the exterior walls to be included, or just the interior area exclusive of the exterior walls?
A:  

For the purposes of calculating the allowable area in OSSC section 503, the IBC Commentary says that the allowable area is the inside face of the exterior wall. However, the panel refers this question to the state for interpretation: www.bcd.oregon.gov/programs/structural/interps/OSSC_Interp_503_area_of_building.pdf 
(Tri-County Code Forum June 2005)


Q:   Will the text given in 302.2.1, which states that assembly spaces that are accessory uses to Group E are not required to be considered separate occupancies be interpreted in Tri-County to mean that there is no occupancy separation required?  Table 302.3.2 indicates separation is required (2-Hour) which seems to be in conflict with 302.2.1. The spaces we are curious about typically include gymnasiums, school cafeteria, and possibly school library.
A:   The code section refers to assembly occupancies that are accessory to Group E, in which case they are not required to be separated. If, by chance, there was an A occupancy adjacent to the E, but under separate control, then they would need the appropriate occupancy separation. (Tri-County Code Forum, September 2004)
Q:   Paragraph 303.1 states that assembly spaces which are accessory to Group E in accordance with 302.2 are not considered assembly occupancies. Will that be the case for K-12 public school buildings in Tri-County? If yes, are these uses classified as E for the purposes of determining occupant load, egress width, etc.?
A:   Section 302.3.1 states that for non-separated uses, all other code requirements shall apply to each portion of the building based on the use of that space. The exiting requirements for the assembly portions of the building need to meet the requirements based on that use. (Tri-County Code Forum, September 2004)
Q:   Please clarify the definition of atrium per 404.1.1 as it relates to an opening in a two-story building.
A:  

The definition in the 2004 OSSC of what constitutes an "atrium" is nearly identical to that found in section 202 of the 1998 OSSC. However, the  companion provisions for "shafts" and "vertical exit enclosures" in the respective code editions have changed considerably.

 

For example, section 711.3 of the 1998 OSSC stated that; "In other than Group I Occupancies, openings that penetrate only one floor and are not connected with openings communicating with other stories or basements and that are not concealed within building construction assemblies need not be enclosed." As such, most required stairways were permitted to atmospherically connect two floors.

 

In contrast, section 707.2, exception 7.2 of the 2004 OSSC will not allow the "required means of egress system" to be unenclosed  between floors except as permitted in section 1019.1. A cursory look at section 1019.1 reveals that the required stairways in the means of egress must be enclosed except for the following circumstances:

 

In other than Group H and I occupancies, a stairway serving an occupant load of less than 10 not more than one story above the level of exit discharge.

In other than occupancy Groups H and I, a maximum of 50 percent of egress stairways serving one adjacent floor are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Any two such interconnected floors shall not be open to other floors.

 

In other than occupancy Groups H and I, interior egress stairways serving only the first and second stories of a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 are not required to be enclosed, provided at least two means of egress are provided from both floors served by the unenclosed stairways. Such interconnected stories shall not be open to other stories.

 

In short, where a sprinkler system is installed, stairways serving the first and second stories may be unenclosed. In unsprinklered buildings, 50 percent of the egress stairways and stairways serving 10 or less persons above the level of exit discharge may be unenclosed.

 

As noted, this is only one example of the differences. Sections 404, 707.2 and 1019.1 contain additional exceptions that warrant further examination and application. (Tri-County Code Forum, March 2005)
Q:   For purposes of applying the requirements for natural light, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural light from the living/dining area?
A:   Yes, if it meets the qualifications of the opening described in Section 1205.2.1. of the 2004 0SSC. (Tri-County Code Forum, September 2004)
Q:   Assuming the "den" is not provided with mechanical ventilation, can the opening between the "den" and the "entry" hallway be considered to meet the qualifications of section 1204.1 such that the "den" can be considered a portion of the living/dining area and can borrow natural ventilation from the living/dining area?
A:   Yes, if the opening meets the minimum opening requirements of Section 1203.4.1.1 of the 2004 OSSC . (Tri-County Code Forum, September 2004)
Q:  

1-4. Code References: 

Section 310.4  Basements in dwelling units and every sleeping room below the fourth story shall have at least one operable window or door approved for emergency escape or rescue that shall open directly to a public street, public alley, yard or exit court.

 

Section 1204.2  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural light by means of exterior glazed openings with an area not less than one tenth the floor area of such rooms with a minimum of 10 square feet.


Section 1204.3  Guest rooms and habitable rooms within a dwelling unit or congregate residence shall be provided with natural ventillation as specified in section 1203.2.4 or by a mechanical ventilation system which shall be capable of supplying ventilation air in accordance with Table 12-A.

 

Section 1204.1  For the purpose of determining the light or ventilation and source control ventilation for Group R Occupancies required by this section and Table 12-A, any room may be considered as a portion of an adjoining room when one half of the area of the common wall is open and unobstructed and provides an opening of not less that one tenth of the floor area of the interior room or 25 square feet, whichever is greater.

 

The floor plans for dwelling units each have an interior room labeled as a "den." In one unit the "den" has a clothes closet. The "den" in the other unit does not have a closet. Assuming these units are not in a building complying with the requirements of chapter 4 for a high rise building, please respond to the following questions:

 

Is the "den" containing the clothes closet considered a sleeping room for purposes of applying emergency egress requirements?  Is the "den" that does not contain a closet considered a sleeping room for purposes of applying emergency egress requirements?

A:   The applicant is required to label the rooms accurately. If the room has a closet and is labeled "den," building departments should accept the designation and make no assumption that it will be used other than how it is labeled. For example, many living rooms have closets but are not treated as sleeping rooms. (Tri-County Code Forum, September 2004)
Q:   We have a clarification request for the next Building Code Forum.  One of our colleagues recently found the following: Under section 105.2 Exceptions 13 (Agricultural Structures) and 14 ( Equine Facilities), the new code refers to ORS 455.310. ORS 455.310 covers exempt residential construction, not agricultural structures. ORS 455.315 covers exempt agricultural structures. See ORS index at http://www.leg.state.or.us/ors/455.html You may want to point this out so that it is addressed in future issuances of the Code.
A:   The wrong statute was cited in the code and will be corrected. (Tri-County Code Forum, March 2005)
Q:   What are the new OSSC requirements for firewalls in apartments?
A:   The new code requires the dwelling unit separation to be one hour, unless the building is sprinkled; then unit separation can be 30 minutes. See also section 708. (Tri-County Code Forum, June 2005)
Q:   Is there a definition for a 30-minute wall?
A:   Table 721.6.2 of the OSSC  assigns a fire-resistive time period to various wall components. Using this table, a designer is able to establish an overall fire-resistive time period for a given assembly by adding up the times assigned to interior and exterior membranes, the wood frame and the addition of certain insulations (unique to wood frame construction). (Tri-County Code Forum, June 2005)
Q:   If the 2-1/2 inch net section is still required by the 2004 Structural Specialty Code, does the minimum net section apply to metal plate connected pre-engineered roof trusses used to anchor masonry or concrete walls?
A:   The prescriptive provisions have been replaced with design provisions. (Tri-County Code Forum, June 2005)
Q:   For ADA access, the code requires 12 inches adjacent to the ?push? side of a door equipped with a closer and a latch. If the latch is panic hardware, is the 12 inches of adjacent space still required?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   When there are several properties under the same ownership how do you treat property lines?
A:   Contact your local jurisdiction. The answer depends on which jurisdiction you?re in and must be judged on a case by case basis. Suggestions from the panel included the use of a covenant (not to sell separately) or a lot line adjustment. (Tri-County Code Forum, September 2004)
Q:  

Are there situations in which an accessible table located adjacent to a bar counter can be provided instead of a 60-inch long portion of the bar counter lowered to 34 inches?

Bar counters in restaurants and lounges are usually 36 to 44 inches high where patrons sit on raised seats. Ice and drink dispensers, coolers, sinks, and other equipment are typically built into the barkeep side of the casework. It is common for small restaurants to propose a 6 to 8 foot long bar.

 

Section 1108.4.5 completely eliminates raised bar counters that are 5 feet long or less. Bar counters less than 10 feet long are impractical because the remaining raised portion is less than 5 feet long. The end result is the restaurant does not have a raised bar, which seems overly restrictive.

 

Note that The Americans with Disabilities Act Accessibility Guidelines (ADAAG) Section 5.2 allows bar service to be provided at accessible tables within the same area as the raised counter.

A:  

Section 1101.6 references ORS 447.250 and allows waivers or modifications if the code section is more restrictive than ADA guidelines or the Fair Housing Act. If the new ADAAG guidelines allow this alternate method, the applicant may be able to appeal to the state. It could also be approved at the local level as an alternate method, but jurisdictions may be hesitant to make this approval without guidance from the state.

 

It would seem that if a table is assigned for use as an "accessible table" and is made available for use when needed that it could fulfill the requirement. However, if the table was in use and was then needed, it could create a slight inconvenience as the current patrons would have to be relocated to make room for the physically challenged user. (Tri-County Code Forum, September 2004)


Q:   Our current project is the restoration of a fire-damaged school. Would this work be considered a "repair," an "addition," or an "alteration"? While most of the project consists of rebuilding the classrooms and does not include adding any new space, the original structure is more than 65 years old and could use some structural updates, as well as the addition of an smoke alarm system. Would such additions change the category of construction?
A:   The work to restore the fire-damaged area would be considered a repair, even if new trusses must be added to be sufficient to carry the load. The fire code  has a retroactive provision that requires smoke alarms in all such buildings. Work with your local building official to discuss details. (Tri-County Code Forum, June 2005)
Q:   Do S2 parking structures need to be sprinklered?
A:   406.4 and 903.2.9 Open, no; enclosed, yes. (Tri-County Code Forum, June 2005)
Q:   Does the shape of the ceiling tiles, whether they are flat or regular, have a  bearing on the grid requirements?
A:   No. (Tri-County Code Forum, June 2005)
Q:   Can tiles be scribed in at all sides and not affect the deflection of the grid?
A:   Yes. (Tri-County Code Forum, June 2005)
Q:   If a ceiling grid system has no tiles or lights directly attached to the grid, does it then become an aesthetic system and not need to meet any of the ceiling grid code requirements?
A:   Any such grid system must meet the structural code requirements. (Tri-County Code Forum, June 2005)
Q:   Please clarify 1621 and referenced ASCE 9.6.2.6.2.2 as it relates to suspended ceiling tile and sprinkler head design.
A:   The panel refers this question to the Building Codes Division for interpretation. It appears that it is extremely difficult for builders to locate sprinklers or seismic joints that are the correct size. (Tri-County Code Forum, March 2005)
Q:   What is the requirement for upper cabinet height?
A:  

UFAS (Kitchen storage) states that " Max. height shall be 48inches for at least one shelf of all cabinets & storage shelves mounted above work counters.? Does that mean one shelf of EACH upper cabinet? Or does that mean just one shelf is required to be mounted at 48 inches and the others can be mounted higher?


UFAS is not the adopted accessibility standard in the State of Oregon. However,  OSSC 1109.11.2, which is based on the Americans with Disabilities Act Architectural Guidelines (ADAAG), requires 50 percent of the cabinets to have at least one shelf within the height limitation. (Tri-County Code Forum, June 2005)


Q:   I have a question for further clarification on a ventilation question related to the Q&A posed during the April 8 forum and answered in the August-October 2004 News Site, specifically Oregon Structural Specialty Code, Section 1505. Can alternate ventilation (gable end vents or extra vents in non-vaulted areas) be installed to compensate for any blocked or restricted soffit vents, due to insulation filled rafter or scissor truss cavities, and achieve a 150:1 venting requirement? Any 2x6, 2x8, 2x10 rafter, for a vaulted ceiling, is simply too small to allow for R-30 Fiberglass Batt insulation and allow 1" air gap. (R-30= 9-1/4(one quarter)" for high density fiberglass insulation, 2x10 =9-1/4(one quarter)"   there is no room for air gap) Any scissor truss is only 3-1/2(one half)" at the soffit vent, and there is no possible way to achieve either R-30 or the required air gap for the first 18" to 36" of the scissor truss cavity (depending upon pitches) There is a conflict between structural codes allowing 2x4 trusses, 2x6, 2x8 and 2x10 rafters, the insulation requirements and ventilation requirements. The insulation gets crammed into rafter spaces and venting is blocked off. When scissor trusses or less than 2x12 rafters are used, the plans examiner should be able to know that mathematically the soffit vents will be blocked. Shouldn't this be the step when alternate venting should be called out? How do we meet all three requirements? We have had call-back on houses that "meet codes" and were signed off, but now have high moisture build-up in the attic and mold growth on the roof sheeting. Obviously the current venting is not working!
A:   The code allows for the compression of roof insulation in sloped roof assemblies in proximity to eave vents. The code also requires the installation of "baffles" in order to maintain cross ventilation. (Tri-County Code Forum, December 2004)
Q:   Please clarify the definition of "walls directly attached to structure."  Do walls that are braced to the structure meet his requirement?
A:   If the wall is bracing a building, or it is relying on the building for its support, it is a part of the structure. (Tri-County Code Forum, June 2005)
Q:   What if you re-stripe?
A:  

If you're repainting the existing stripes in an existing lot over the existing stripes, that is fine, the repainting of the stripe can be to match existing stripes. If you want to move spaces or change the configuration, you can do so as long as you comply with the code in existence at the time of reconfiguring the parking lot. (Tri-County Building Code Forum, December 17, 2001)


Q:   The 1998 Structural Specialty Code based on the 1997 UBC Section 1633.2.8.1. Item 5 requires that wood elements of a concrete or masonry wall anchorage system "have a minimum actual net thickness of 2 1/2 inches."  Does the current 2004 Structural Specialty Code based on the 2003 IBC have an equivalent requirement?  If yes, where is the citation requiring 2-1/2 inch (3x)wood elements for the anchorage of concrete or masonry wall systems?
A:   No. There is nothing in the current code that addresses this issue. (Tri-County Code Forum, June 2005)