Appeal 33590

1007.1.1, exception 1

Where two exits, exit access stairways or ramps, or any combination thereof, are requiredfrom any portion of the of the exit access, they shall be placed a distance apart equal tonot less one-half of the length of the maximum overall diagonal dimension of the buildingor area to be served measured in a straight line between them. Interlocking or scissorstairways shall be counted as one exit stairway.

Exception 1 – Where interior exit stairways or ramps are interconnected by a 1-hour fire-resistance-rated corridor conforming to the requirements of Section 1020, the requiredexit separation shall be measured along the shortest direct line of travel within thecorridor.

(Summarize the intent of the appeal, preferably in one sentence.)
This appeal is to provide the egress balcony with 1 hour rated walls, 45 minute rated doors,and sprinklered unprotected windows to provide the 1 hour rated corridor required forexit doors less than 1/3 diagonal apart.

Reconsideration of Appeal
With the addition of 45 minute rated operable windows with fusible link and rated frameand fixed glass panel above.

The building is a Type VA 4 story multi-family, fully sprinklered building organized around acentral, exterior courtyard with egress balconies serving each dwelling unit on the fourfloors. The exit stairway is an interlocking stair serving the 4 floors with 2 hour ratedseparation between the stairs.

The proposed design meets the requirements of the code except the doors into theinterlocking stairs are less than 1/3 diagonal apart in the sprinklered building. Exception 1of 1007.1.1 allows the separation to be measured through a 1 hour rated corridor. Theseparation distance meets the requirements of exception 1 except the exit separationdistance will be measured along an exterior egress balcony. Equivalent protection isprovided by 1 hour separation between the units and the egress balcony with exit stairs ateach end.
The proposed design of the unit seaprtaion is proposed as follows:

•1 hour rated walls
•45 minute rated doors
•Sidewall sprinkler heads over windows spaced no more than 6’ o.c.
•45 minute rated window w/ (1) fixed panel of glass and (1) operable panel of glass withfusible link

Reconsideration of Appeal
5 operable window units (w/ fixed panels above) have been located within the arearequired to be 1hr protected. In order to comply with Natural Ventilation requirements of2022 OSSC 1202.5.1, and to provide the basic function of an operable window at theseresidential units and to increase occupant comfort. The proposal is to utilize fire ratedoperable windows at (5) openings (w/ fixed panels above). The specified window system isa single mulled steel frame unit with a fixed panel above and an operable panel below. Theawning window (operable panel) will include a fusible link that closes the operable panelupon exposure to heat. The specified window system is UL listed and tested per ASTM. Theproposed fire rating for these (5) windows and glazing is 3/4 hour as required.

The fully sprinklered building requires the exit doors to the stairs to be no less than 1/3diagonal apart. The use of an interlocking stair that is compliant as being 2 means ofegress, as they are separated by 2 hour rated assemblies. The use of the interlocking stairsmeans that the exit doors to the stairs are less than 1/3 diagonal apart.

OSSC 1007.1.1, exception 1 allows the exit seaprtaion distance to be measured along thepath of a 1 hour rated corridor. This building does not have corridors, using exterior egressbalconies to access the stairs. The egress balconies meet all the requirements of egressbalconies with the exit access doors preventing any dead ends.

The proposed design is to use the egress balconies with 1 hour rated separation betweenthe units, with sprinklered glass, and the balconies. These separated egress balconies thatare open to the air provide equivalent protection to a 1 hour rated corridor, allowing theexit access doors into the interlocking stairs to be less than 1/3 diagonal distance apart.

The proposed design for the 1 hour separation walls are 1 hour rated fire barriers with 45minute rated doors as required for openings in a corridor. Windows that are open to theegress balconies from the units will not be rated assemblies, but will be protected on theunit side with sprinklers 4”-12” grom the glass and no more than 6’ apart. The balcony side of the windows will be provided with sidewall sprinklers within 12” of the solid floorbalcony above and spaced no more than 6’ apart.

By providing the sprinklered glass and 1 hour rated fire barrier walls along the egressbalcony, the proposed design provides equivalent protection to OSSC 1007.1.1, exception 1and request approval of this appeal.

Reconsideration of Appeal
The proposed reconsideration utilizes fire rated windows and glazing with steel frames at(5)locations – which benefit occupant comfort and enhance livability. This method hasbeen granted in many previous building code appeals in the City of Portland – see Appeal16852 Item #1, 24506 Item #1 and 24740 #1 for examples. The use of fusible link windowsystems provide the required protection and are an equivalent level of protection andsafety. All other unprotected openings to be sprinklered as previously appealed (please seeelavations for further information).