Pre-Approved Building Code Alternatives
The City of Vancouver has adopted two approved code alternate compliance paths for new residential development. The interim policies allow architects and builders to begin using these design approaches while broader code work continues at the state level.
Single-stair building design allows certain mid-rise residential buildings to be served by one stair rather than two, when enhanced life-safety standards are met. The approach is increasingly used to support efficient building layouts and expand housing options.
Six-story wood construction allows buildings that would have traditionally been constructed above a raised concrete podium, to be constructed entirely out of wood framing, lowering costs and construction time without reducing safety.
By recognizing Seattle and Tacoma’s established code framework as approved alternates, Vancouver is enabling local design teams to move forward with projects that use the model while maintaining safety standards. The policy provides a clear pathway for architects and builders interested in incorporating these configurations in qualifying projects.
City staff will continue coordinating with state agencies, industry professionals, and regional partners as the statewide code development advances.
For additional information, project teams are encouraged to contact our Plan Review Team or call 360-487-7828
Single-Stair Code Alternative
Not more than 5 stories of Group R-2 occupancy are permitted to be served by a single exit under the following conditions:
Building Size
- The building has not more than six stories above grade plane.
- There shall be no more than four dwelling units on any floor.
Building Use
- The building does not contain a boarding house.
- Other occupancies are permitted in the same building provided they comply with all the requirements of this code.
- Other occupancies shall not communicate with the Group R occupancy portion of the building or with the single-exit stairway.
- Exception: parking garages and occupied roofs accessory to the Group R occupancy are permitted to communicate with the exit stairway.
Fire Protection
- The building shall be of not less than one hour fire-resistive construction and shall also be equipped throughout with an automatic sprinkler system in accordance with subsection 903.3.1.1 (NFPA 13 sprinkler protection).
Exiting and Stairways
- There shall be no more than two single exit stairway conditions on the same property.
- An exterior stairway or interior exit stairway shall be provided.
- The interior exit stairway, including any related exit passageway, shall be pressurized in accordance with subsection 909.20
- Doors in the stairway shall swing into the interior exit stairway regardless of the occupant load served, provided that doors from the interior exit stairway to the building exterior are permitted to swing in the direction of exit travel.
- A corridor shall separate each dwelling unit entry/exit door from the door to an interior exit stairway, including any related exit passageway, on each floor.
- Dwelling unit doors shall not open directly into an interior exit stairway.
- Dwelling unit doors are permitted to open directly into an exterior stairway.
- There shall be no more than 20 feet (6096 mm) of travel to the exit stairway from the entry/exit door of any dwelling unit.
- Travel distance measured in accordance with section 1017 shall not exceed 125 feet (38100 mm).
- The exit shall not terminate in an egress court where the court depth exceeds the court width unless it is possible to exit in either direction to the public way.
- The exit serving the Group R occupancy shall not discharge through any other occupancy, including an accessory parking garage.
- There shall be no openings within 10 feet (3048 mm) of unprotected openings into the stairway other than required exit doors having a one-hour fire-resistance rating.
Elevators
- Elevators shall be pressurized in accordance with section 909.21 or shall open into elevator lobbies that comply with section 713.14.
Six Story Wood Construction Code Alternative
Up to 6 stories of Group R-2 occupancy are permitted to be built using Type III-A construction under the following conditions.
Building Size
- The building has not more than six stories above grade plane.
- The building has a maximum roof height limit of 85 feet
- The building must meet IBC Chapter 5 requirements for allowable area
Building Use
- The building shall be Group R-2 residential
- Other related occupancies, such as a leasing office, are allowed, but must qualify as accessory use (less than 10% of the floor area)
Fire Protection
- The building shall be of not less than one hour fire-resistive construction and shall also be equipped throughout with an automatic sprinkler system in accordance with subsection 903.3.1.1 (NFPA 13 sprinkler protection).
- The first story of Type III-A construction is separated from stories above with a horizontal assembly having a fire-resistance rating per the applicable code provision.
Stairways and Mezzanines
- Unprotected vertical openings, including unenclosed interior exit access stairways, shall not penetrate floor/ceiling assemblies between stories of Type IIIA construction.
- Mezzanines and occupied roof decks are not permitted.
Additional Requirements
The building must meet one of the following options in its entirety:
Option 1: Tacoma Municipal Code
Amendment to IBC Section 504.4 – Number of Stories – by amending subsection 504.4.1 WA State amendment to the IBC and by addition of a new Section 504.4.1.1 – Type B occupancies within R-1 and R-2 occupancies.
The following section amends Section 504.4.1 of the State Building Code amendments to IBC Section 504.4 – Number of Stories, by replacing 504.4.1 in its entirety, and by addition of a new Section 5.4.4.1.1.
Tacoma Building Code 504.4.1 Stair Enclosure Pressurization Increase. For Groups R-1 and R-2 in buildings of Type VA or IIIA construction, or I-1 Condition 2 Assisted living facilities licensed per chapter 388-78A WAC and residential treatment facilities as licensed by Washington state under chapter 246-337 WAC located in buildings of Type VA construction equipped throughout with an approved automatic sprinkler system in accordance with Section 903.3.1.1, the maximum number of stories permitted in Section 504.4 may be increased by one provided the interior exit stairways and ramps are pressurized in accordance with Sections 909.6.3 and 909.20.
Option 2: Seattle Building Code
Seattle Building Code Chapter 5 – General Building Heights and Areas
SBC.510 – Special Provisions
510.10 Group R-2 Buildings of Type IIIA Construction
The height limitation for buildings of Type IIIA construction in Group R-2 shall be increased to six stories where all of the following conditions are met:
- The first story of Type IIIA construction is separated from stories above with a horizontal assembly having a fire-resistance rating of not less than 2 hours. Fire-resistance rated mass timber is permitted in the horizontal assembly and its supporting structure.
- All stories of Type IIIA construction greater than 6,000 gross square feet shall be subdivided into compartments, by 2-hour fire-resistance rated fire walls, with areas of not more than 12,000 gross square feet.
- Each compartment shall have an enclosed exit stairway, and a standpipe in accordance with Section 905.
- Unprotected vertical openings, including unenclosed interior exit access stairways, shall not penetrate floor/ceiling assemblies between stories of Type IIIA construction.
- Mezzanines shall not be allowed in any story of the Type IIIA construction.
- The maximum total design dead load shall be 50 psf for all roof areas above the sixth story of Type IIIA construction.
