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Chapter 51-50 WAC

Last Update: 7/29/21

STATE BUILDING CODE ADOPTION AND AMENDMENT OF THE 2018 EDITION OF THE INTERNATIONAL BUILDING CODE

(Formerly chapter 51-40 WAC)

WAC Sections

HTMLPDF51-50-001Authority.
HTMLPDF51-50-002Purpose.
HTMLPDF51-50-003International Building Code.
HTMLPDF51-50-005International Building Code requirements for barrier-free accessibility.
HTMLPDF51-50-007Exceptions.
HTMLPDF51-50-008Implementation.
HTMLPDF51-50-009Recyclable materials, compost, and solid waste storage.
HTMLPDF51-50-0108Temporary structures and uses.
HTMLPDF51-50-0110Section inspections.
HTMLPDF51-50-0200Chapter 2—Definitions.
HTMLPDF51-50-0303Section 303—Assembly Group A.
HTMLPDF51-50-0305Section 305—Educational Group E.
HTMLPDF51-50-0306Section 306—Factory Group F.
HTMLPDF51-50-0308Section 308—Institutional Group I.
HTMLPDF51-50-0309Section 309—Mercantile Group M.
HTMLPDF51-50-0310Section 310—Residential Group R.
HTMLPDF51-50-0312Reserved.
HTMLPDF51-50-0403Section 403—High-rise buildings.
HTMLPDF51-50-0406Reserved.
HTMLPDF51-50-0407Section 407—Group I-2.
HTMLPDF51-50-0412Section 412—Aircraft-related occupancies.
HTMLPDF51-50-0420Section 420—Groups I-1, R-1, R-2, R-3.
HTMLPDF51-50-0422Section 422—Ambulatory care facilities.
HTMLPDF51-50-0427Reserved.
HTMLPDF51-50-0429Section 429—Electric vehicle charging infrastructure.
HTMLPDF51-50-0502Reserved.
HTMLPDF51-50-0503Section 503—General building height and area limitations.
HTMLPDF51-50-0504Section 504—Building height and number of stories.
HTMLPDF51-50-0505Reserved.
HTMLPDF51-50-0506Section 506—Building area.
HTMLPDF51-50-0508Section 508—Mixed use and occupancy.
HTMLPDF51-50-0509Section 509—Incidental uses.
HTMLPDF51-50-0510Section 510—Special provisions.
HTMLPDF51-50-0601Section 601—General.
HTMLPDF51-50-0602Section 602—Construction classification.
HTMLPDF51-50-0603Section 603—Combustible material in Types I and II construction.
HTMLPDF51-50-0703Section 703—Fire-resistance ratings and fire tests.
HTMLPDF51-50-0704Section 704—Fire-resistance rating of structural members.
HTMLPDF51-50-0705Section 705—Exterior walls and projections.
HTMLPDF51-50-0706Section 706—Fire walls.
HTMLPDF51-50-07070Section 707—Fire barriers.
HTMLPDF51-50-0708Section 708—Reserved.
HTMLPDF51-50-0710Section 710—Reserved.
HTMLPDF51-50-0713Section 713—Shaft enclosures.
HTMLPDF51-50-0716Section 716—Opening protectives.
HTMLPDF51-50-0717Section 717—Ducts and air transfer openings.
HTMLPDF51-50-0718Section 718—Concealed spaces.
HTMLPDF51-50-0722Section 722—Calculated fire resistance.
HTMLPDF51-50-0803Section 803—Wall and ceiling finishes.
HTMLPDF51-50-0902Section 902—Reserved.
HTMLPDF51-50-0903Section 903—Automatic sprinkler systems.
HTMLPDF51-50-0907Section 907—Fire alarm and detection systems.
HTMLPDF51-50-0908Section 908—Reserved.
HTMLPDF51-50-0909Section 909—Smoke control systems.
HTMLPDF51-50-0911Section 911—Reserved.
HTMLPDF51-50-0913Section 913—Fire pumps.
HTMLPDF51-50-0915Section 915—Carbon monoxide detection.
HTMLPDF51-50-1004Section 1004—Occupant load.
HTMLPDF51-50-1005Section 1005—Reserved.
HTMLPDF51-50-1006Section 1006—Number of exits and exit access doorways.
HTMLPDF51-50-1007Section 1007—Reserved.
HTMLPDF51-50-1008Section 1008—Means of egress illumination.
HTMLPDF51-50-1009Section 1009—Accessible means of egress.
HTMLPDF51-50-10100Section 1010—Doors, gates, and turnstiles.
HTMLPDF51-50-1011Section 1011—Stairways.
HTMLPDF51-50-1012Section 1012—Ramps.
HTMLPDF51-50-1014Reserved.
HTMLPDF51-50-1015Reserved.
HTMLPDF51-50-1018Section 1018—Reserved.
HTMLPDF51-50-1019Section 1019—Exit access stairways and ramps.
HTMLPDF51-50-1020Section 1020—Corridors.
HTMLPDF51-50-1023Section 1023—Interior exit stairways and ramps.
HTMLPDF51-50-10240Section 1024—Exit passageways.
HTMLPDF51-50-1028Reserved.
HTMLPDF51-50-10300Section 1030—Emergency escape and rescue.
HTMLPDF51-50-1101Section 1101—General.
HTMLPDF51-50-11050Section 1105—Accessible entrances.
HTMLPDF51-50-1106Section 1106—Parking and passenger loading facilities.
HTMLPDF51-50-1107Section 1107—Dwelling units and sleeping units.
HTMLPDF51-50-11090Section 1109—Other features and facilities.
HTMLPDF51-50-1202Section 1202—Ventilation.
HTMLPDF51-50-1203Section 1203—Temperature control.
HTMLPDF51-50-1204Section 1204—Temperature control.
HTMLPDF51-50-1206Section 1206—Sound transmission.
HTMLPDF51-50-1207Section 1207—Interior space dimensions.
HTMLPDF51-50-1208Reserved.
HTMLPDF51-50-1209Section 1209—Toilet and bathroom requirements.
HTMLPDF51-50-1210Section 1210—Reserved.
HTMLPDF51-50-1403Section 1403—Performance requirements.
HTMLPDF51-50-1405Section 1405—Reserved.
HTMLPDF51-50-1406Reserved.
HTMLPDF51-50-1602Reserved.
HTMLPDF51-50-1604Section 1604—General design requirements.
HTMLPDF51-50-1607Reserved.
HTMLPDF51-50-1609Section 1609—Reserved.
HTMLPDF51-50-1613Section 1613—Earthquake loads.
HTMLPDF51-50-1615Tsunami loads.
HTMLPDF51-50-1702Section 1702—Definitions.
HTMLPDF51-50-1705Section 1705—Required special inspections and tests.
HTMLPDF51-50-17090Preconstruction load tests.
HTMLPDF51-50-1710Section 1710—Reserved.
HTMLPDF51-50-1715Section 1715—Reserved.
HTMLPDF51-50-1807Section 1807—Foundation walls, retaining walls and embedded posts and poles.
HTMLPDF51-50-1901Section 1901—Reserved.
HTMLPDF51-50-1903Section 1903—Reserved.
HTMLPDF51-50-1904Section 1904—Reserved.
HTMLPDF51-50-1905Section 1905—Reserved.
HTMLPDF51-50-1908Section 1908—Reserved.
HTMLPDF51-50-1909Section 1909—Reserved.
HTMLPDF51-50-2104Section 2104—Reserved.
HTMLPDF51-50-2106Reserved.
HTMLPDF51-50-21070Section 2107—Allowable stress design.
HTMLPDF51-50-2108Section 2108—Reserved.
HTMLPDF51-50-2111Section 2111—Masonry fireplaces.
HTMLPDF51-50-2114Reserved.
HTMLPDF51-50-2115Section 2115—Emission standards.
HTMLPDF51-50-2303Section 2303—Minimum standards and quality.
HTMLPDF51-50-2304Section 2304—General construction requirements.
HTMLPDF51-50-2400Chapter 24—Glass and glazing.
HTMLPDF51-50-2407Reserved.
HTMLPDF51-50-2603Reserved.
HTMLPDF51-50-2702Section 2702—Emergency and standby power systems.
HTMLPDF51-50-2900Chapter 29—Plumbing systems.
HTMLPDF51-50-3001Reserved.
HTMLPDF51-50-30020Reserved.
HTMLPDF51-50-3004Section 3004—Reserved.
HTMLPDF51-50-30050Section 3005—Machine rooms.
HTMLPDF51-50-3006Section 3006—Elevators and conveying systems.
HTMLPDF51-50-3009Reserved.
HTMLPDF51-50-3101Section 3101—General.
HTMLPDF51-50-3102Section 3102—Membrane structures.
HTMLPDF51-50-3103Temporary structures.
HTMLPDF51-50-3108Section 3108—Reserved.
HTMLPDF51-50-3109Section 3109—Swimming pools, spas and other water recreation devices.
HTMLPDF51-50-3114Section 3114—Fixed guideway transit and passenger rail systems.
HTMLPDF51-50-3304Section 3304—Site work.
HTMLPDF51-50-3401Section 3401—Reserved.
HTMLPDF51-50-3404Section 3404—Reserved.
HTMLPDF51-50-3410Section 3410—Reserved.
HTMLPDF51-50-3411Section 3411—Reserved.
HTMLPDF51-50-3500Chapter 35—Referenced standards.
HTMLPDF51-50-4700Appendix D—Fire districts.
HTMLPDF51-50-4800002015 International Existing Building Code.
INTERNATIONAL EXISTING BUILDING CODE
2018 EDITION
HTMLPDF51-50-480101Section 101—General.
HTMLPDF51-50-480102Section 102—Reserved.
HTMLPDF51-50-480200Section 201.3—Definitions.
HTMLPDF51-50-480302Section 302—General Provisions.
HTMLPDF51-50-480305Reserved.
HTMLPDF51-50-480307Section 307—Reserved.
HTMLPDF51-50-480403Reserved.
HTMLPDF51-50-480405Section 405—Reserved.
HTMLPDF51-50-480407Reserved.
HTMLPDF51-50-480408Section 408—Plumbing.
HTMLPDF51-50-480409Reserved.
HTMLPDF51-50-480410Reserved.
HTMLPDF51-50-480505Reserved.
HTMLPDF51-50-480506Section 506—Change of occupancy.
HTMLPDF51-50-480607Section 607—Reserved.
HTMLPDF51-50-480702Section 702—Building elements and materials.
HTMLPDF51-50-480704Section 704—Reserved.
HTMLPDF51-50-480705Reserved.
HTMLPDF51-50-480707Reserved.
HTMLPDF51-50-480708Energy conservation.
HTMLPDF51-50-480711Section 711—Reserved.
HTMLPDF51-50-480804Reserved.
HTMLPDF51-50-480807Section 807—Reserved.
HTMLPDF51-50-480808Section 808—Reserved.
HTMLPDF51-50-480809Section 809—Plumbing.
HTMLPDF51-50-480810Energy conservation.
HTMLPDF51-50-480811Reserved.
HTMLPDF51-50-480906Reserved.
HTMLPDF51-50-480907Energy conservation.
HTMLPDF51-50-480908Reserved.
HTMLPDF51-50-480912Section 912—Reserved.
HTMLPDF51-50-481002Section 1002—Special use and occupancy.
HTMLPDF51-50-481009Section 1009—Plumbing.
HTMLPDF51-50-481012Reserved.
HTMLPDF51-50-481101Section 1101—Change of occupancy classification.
HTMLPDF51-50-481102Reserved.
HTMLPDF51-50-481103Section 1103—Reserved.
HTMLPDF51-50-481104Reserved.
HTMLPDF51-50-481105Section 1105—Reserved.
HTMLPDF51-50-481106Reserved.
HTMLPDF51-50-481201Section 1201—Historic buildings—General.
HTMLPDF51-50-481203Fire safety.
HTMLPDF51-50-481204Reserved.
HTMLPDF51-50-481205Reserved.
HTMLPDF51-50-481301Relocated or moved buildings—General.
HTMLPDF51-50-481302Requirements.
HTMLPDF51-50-481500Section 1501—General.
HTMLPDF51-50-490000Appendix N—Solar readiness.
DISPOSITION OF SECTIONS FORMERLY CODIFIED IN THIS TITLE
51-50-004Conflicts with Washington State Ventilation and Indoor Air Quality Code. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-004, filed 12/17/03, effective 7/1/04.] Repealed by WSR 10-03-097, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.031 and 19.27.074.
51-50-0107Temporary structures and uses. [Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0107, filed 12/19/06, effective 7/1/07.] Amended and decodified by WSR 10-03-097, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.031 and 19.27.074. Recodified as § 51-50-0108.
51-50-0302Section 302—Classification. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0302, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-0313Section 313—Licensed Care Group LC. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0313, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-0419Section 419—Group LC. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0419, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-0707Section 707—Shaft enclosures. [Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0707, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0707, filed 12/17/03, effective 7/1/04.] Amended and decodified by WSR 10-03-097, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.031 and 19.27.074. Recodified as § 51-50-0708.
51-50-1010Section 1010—Ramps. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-1010, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-1017Corridors. [Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-1017, filed 12/19/06, effective 7/1/07.] Amended and decodified by WSR 10-03-097, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.031 and 19.27.074. Recodified as § 51-50-1018.
51-50-1024Section 1024—Assembly. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-1024, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-1030Emergency escape and rescue. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-1030, filed 1/19/16, effective 7/1/16.] Repealed by stipulated order 16-2-00594-34 of Thurston County Superior Court, WSR 16-11-018, filed 5/6/16, effective 6/30/16.
51-50-1103Section 1103—Scoping requirements. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-1103, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-1104Section 1104—Accessible route. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-1104, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-1105Section 1105—Accessible entrances. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-1105, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-1109Section 1109—Other features and facilities. [Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074 and chapters 19.27 and 34.05 RCW. WSR 05-01-014, § 51-50-1109, filed 12/2/04, effective 7/1/05. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-1109, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-1605Section 1605—Load combinations. [Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074 and chapters 19.27 and 34.05 RCW. WSR 05-01-014, § 51-50-1605, filed 12/2/04, effective 7/1/05.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-1709Section 1709—Structural observations. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-1709, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-1714Section 1714—Preconstruction load tests. [Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-1714, filed 12/19/06, effective 7/1/07.] Amended and decodified by WSR 10-03-097, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.031 and 19.27.074. Recodified as § 51-50-1715.
51-50-2107Section 2107—Working stress design. [Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074 and chapters 19.27 and 34.05 RCW. WSR 05-01-014, § 51-50-2107, filed 12/2/04, effective 7/1/05.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-2406Section 2406—Safety glazing. [Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074 and chapters 19.27 and 34.05 RCW. WSR 05-24-070, § 51-50-2406, filed 12/5/05, effective 7/1/06.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-3002Section 3002—Hoistway enclosures. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-3002, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-3003Section 3003—Emergency operations. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-3003, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-3005Section 3005—Conveying systems. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-3005, filed 12/17/03, effective 7/1/04.] Repealed by WSR 07-01-091, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW.
51-50-31200Section 31-2—Standard test method for particulate emissions from fireplaces. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-31200, filed 12/17/03, effective 7/1/04.] Repealed by WSR 13-04-067, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW.
51-50-3408Section 3408—Moved structures. [Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-3408, filed 12/17/03, effective 7/1/04.] Amended and decodified by WSR 10-03-097, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.031 and 19.27.074. Recodified as § 51-50-3410.
51-50-3409Section 3409—Accessibility for existing buildings. [Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-3409, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-3409, filed 12/17/03, effective 7/1/04.] Amended and decodified by WSR 10-03-097, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.031 and 19.27.074. Recodified as § 51-50-3411.


PDF51-50-001

Authority.

These rules are adopted under the authority of chapter 19.27 RCW.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-001, filed 12/17/03, effective 7/1/04.]



PDF51-50-002

Purpose.

The purpose of these rules is to implement the provisions of chapter 19.27 RCW, which provides that the state building code council shall maintain the State Building Code in a status which is consistent with the purpose as set forth in RCW 19.27.020. In maintaining the codes the council shall regularly review updated versions of the codes adopted under the act, and other pertinent information, and shall amend the codes as deemed appropriate by the council.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-002, filed 12/17/03, effective 7/1/04.]



PDF51-50-003

International Building Code.

The 2018 edition of the International Building Code, including Appendix E, published by the International Code Council is hereby adopted by reference with the exceptions noted in this chapter of the Washington Administrative Code.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-003, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-003, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-003, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-003, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-003, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074 and chapters 19.27 and 34.05 RCW. WSR 05-01-014, § 51-50-003, filed 12/2/04, effective 7/1/05. Statutory Authority: RCW 19.27.190, 19.27.020, and chapters 19.27 and 34.05 RCW. WSR 04-18-033, § 51-50-003, filed 8/25/04, effective 9/25/04. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-003, filed 12/17/03, effective 7/1/04.]



PDF51-50-005

International Building Code requirements for barrier-free accessibility.

Chapter 11 and other International Building Code requirements for barrier-free access, including ICC A117.1-2009 and Appendix E, are adopted pursuant to chapters 70.92 and 19.27 RCW.
Pursuant to RCW 19.27.040, Chapter 11 and requirements affecting barrier-free access shall not be amended by local governments.
[Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-005, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-005, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074 and chapters 19.27 and 34.05 RCW. WSR 05-01-014, § 51-50-005, filed 12/2/04, effective 7/1/05. Statutory Authority: RCW 19.27.190, 19.27.020, and chapters 19.27 and 34.05 RCW. WSR 04-18-033, § 51-50-005, filed 8/25/04, effective 9/25/04. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-005, filed 12/17/03, effective 7/1/04.]



PDF51-50-007

Exceptions.

The exceptions and amendments to the International Building Code contained in the provisions of chapter 19.27 RCW shall apply in case of conflict with any of the provisions of these rules.
The provisions of this code do not apply to temporary growing structures used solely for the commercial production of horticultural plants including ornamental plants, flowers, vegetables, and fruits. "Temporary growing structure" means a structure that has the sides and roof covered with polyethylene, polyvinyl, or similar flexible synthetic material and is used to provide plants with either frost protection or increased heat retention. A temporary growing structure is not considered a building for purposes of this code.
The provisions of this code do not apply to the construction, alteration, or repair of temporary worker housing except as provided by rule adopted under chapter 70.114A RCW or chapter 37, Laws of 1998 (SB 6168). "Temporary worker housing" means a place, area, or piece of land where sleeping places or housing sites are provided by an employer for his or her employees or by another person, including a temporary worker housing operator, who is providing such accommodations for employees, for temporary, seasonal occupancy, and includes "labor camps" under RCW 70.54.110.
Codes referenced which are not adopted through RCW 19.27.031 or chapter 19.27A RCW shall not apply unless specifically adopted by the authority having jurisdiction. The 2015 International Existing Building Code is included in the adoption of this code in Section 101.4.7 and amended in WAC 51-50-480000.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-007, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-007, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-007, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-007, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-007, filed 12/17/03, effective 7/1/04.]



PDF51-50-008

Implementation.

The International Building Code adopted under chapter 51-50 WAC shall become effective in all counties and cities of this state on February 1, 2021.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 21-11-066, § 51-50-008, filed 5/14/21, effective 6/14/21; WSR 20-01-090, § 51-50-008, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-008, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-008, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-008, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-008, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-008, filed 12/17/03, effective 7/1/04.]



PDF51-50-009

Recyclable materials, compost, and solid waste storage.

For the purposes of this section, the following definitions shall apply:
COMPOST means biodegradable solid wastes that are separated for composting such as food waste, food soiled paper and yard waste.
RECYCLED MATERIALS means those solid wastes that are separated for recycling or reuse, such as papers, metals and glass.
All local jurisdictions shall require that space be provided for the storage of recycled materials, compost, and solid waste for all new buildings.
EXCEPTION:
Group R-3 and Group U Occupancies.
The storage area shall be designed to meet the needs of the occupancy, efficiency of pickup, and shall be available to occupants and haulers.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-009, filed 1/19/16, effective 7/1/16; WSR 04-01-108, § 51-50-009, filed 12/17/03, effective 7/1/04.]



PDF51-50-0108

Temporary structures and uses.

108.1 General. The building official is authorized to issue a permit for temporary structures and temporary uses. Such permits shall be limited as to time of service, but shall not be permitted for more than 180 days. The building official is authorized to grant extensions for demonstrated cause.
EXCEPTION:
The building official may authorize unheated tents and yurts under 500 square feet accommodating an R-1 Occupancy for recreational use as a temporary structure and allow them to be used indefinitely.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, amended and recodified as § 51-50-0108, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0107, filed 12/19/06, effective 7/1/07.]



PDF51-50-0110

Section inspections.

110.3.5 Type IV-A, IV-B, and IV-C connection protection inspection. In buildings of Type IV-A, IV-B, and IV-C construction, where connection fire-resistance ratings are provided by wood cover calculated to meet the requirements of Section 2304.10.1, inspection of the wood cover shall be made after the cover is installed, but before any other coverings or finishes are installed.
110.3.6 Lath, gypsum board and gypsum panel product inspection. Lath, gypsum board and gypsum panel product inspections shall be made after lathing, gypsum board and gypsum panel products, interior and exterior, are in place, but before any plastering is applied or gypsum board and gypsum panel product joints and fasteners are taped and finished.
EXCEPTION:
Gypsum board and gypsum panel products that are not part of a fire-resistance-rated assembly or a shear assembly.
110.3.7 Weather-exposed balcony and walking surface waterproofing. Where balconies or other elevated walking surfaces are exposed to water from direct or blowing rain, snow or irrigation, and the structural framing is protected by an impervious moisture barrier, all elements of the impervious moisture barrier system shall not be concealed until inspected and approved.
EXCEPTION:
Where special inspections are provided in accordance with Section 1705.1.1, Item 3.
110.3.8 Fire- and smoke-resistant penetrations. Protection of joints and penetrations in fire-resistance-rated assemblies, smoke barriers and smoke partitions shall not be concealed from view until inspected and approved.
110.3.9 Energy efficiency inspections. Inspections shall be made to determine compliance with Chapter 13 and shall include, but not be limited to, inspections for: Envelope insulation R- and U-values, fenestration U-value, duct system R-value, and HVAC and water-heating equipment efficiency.
110.3.10 Other inspections. In addition to the inspections specified in Sections 110.3.1 through 110.3.8, the building official is authorized to make or require other inspections of any construction work to ascertain compliance with the provisions of this code and other laws that are enforced by the department of building safety.
110.3.11 Special inspections. For special inspections, see Chapter 17.
110.3.12 Final inspection. The final inspection shall be made after all work required by the building permit is completed.
110.3.12.1 Flood hazard documentation. If located in a flood hazard area, documentation of the elevation of the lowest floor as required in Section 1612.4 shall be submitted to the building official prior to the final inspection.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-21-021, § 51-50-0110, filed 10/9/20, effective 11/9/20.]



PDF51-50-0200

Chapter 2Definitions.

SECTION 202—DEFINITIONS.
ADULT FAMILY HOME. A dwelling, licensed by the state of Washington department of social and health services, in which a person or persons provide personal care, special care, room and board to more than one but not more than six adults who are not related by blood or marriage to the person or persons providing the services. An existing adult family home may provide services to up to eight adults upon approval from the department of social and health services in accordance with RCW 70.128.066.
ASSISTED LIVING FACILITY. A home or other institution, licensed by the state of Washington, providing housing, basic services and assuming general responsibility for the safety and well-being of residents under chapters 18.20 RCW and 388-78A WAC. These facilities may provide care to residents with symptoms consistent with dementia requiring additional security measures.
BOTTLE FILLING STATION. A plumbing fixture connected to the potable water distribution system and sanitary drainage system that is designed and intended for filling personal use drinking water bottles or containers not less than 10 inches (254 mm) in height. Such fixtures can be separate from or integral to a drinking fountain and can incorporate a water filter and a cooling system for chilling the drinking water.
CHILD CARE. The care of children during any period of a 24-hour day.
CHILD CARE, FAMILY HOME. A child care facility, licensed by Washington state, located in the dwelling of the person or persons under whose direct care and supervision the child is placed, for the care of twelve or fewer children, including children who reside at the home.
CLIMATE ZONE. A geographical region that has been assigned climatic criteria as specified in the Washington State Energy Code.
CLUSTER. Clusters are multiple portable school classrooms separated by less than the requirements of the building code for separate buildings.
EFFICIENCY DWELLING UNIT. A dwelling unit where all permanent provisions for living, sleeping, eating and cooking are contained in a single room.
HOSPICE CARE CENTER. A building or portion thereof used on a 24-hour basis for the provision of hospice services to terminally ill inpatients.
MASS TIMBER. Structural elements of Type IV construction primarily of solid, built-up, panelized or engineered wood products that meet minimum cross section dimensions of Type IV construction.
NIGHTCLUB. An A-2 Occupancy use under the 2006 International Building Code in which the aggregate area of concentrated use of unfixed chairs and standing space that is specifically designated and primarily used for dancing or viewing performers exceeds three hundred fifty square feet, excluding adjacent lobby areas. "Nightclub" does not include theaters with fixed seating, banquet halls, or lodge halls.
NONCOMBUSTIBLE PROTECTION (For MASS TIMBER). Noncombustible material, in accordance with Section 703.5, designed to increase the fire-resistance rating and delay the combustion of mass timber.
PORTABLE SCHOOL CLASSROOM. A prefabricated structure consisting of one or more rooms with direct exterior egress from the classroom(s). The structure is transportable in one or more sections and is designed to be used as an educational space with or without a permanent foundation. The structure shall be capable of being demounted and relocated to other locations as needs arise.
RESIDENTIAL SLEEPING SUITES. A unit that provides multiple rooms or spaces for up to five residents, includes provisions for sleeping and can include provisions for living, eating, sanitation, and kitchen facilities.
SMALL BUSINESS. Any business entity (including a sole proprietorship, corporation, partnership or other legal entity) which is owned and operated independently from all other businesses, which has the purpose of making a profit, and which has fifty or fewer employees.
STAGED EVACUATION. A method of emergency response, that engages building components and trained staff to provide occupant safety during an emergency. Emergency response involves moving or holding certain occupants at temporary locations for a brief period of time before evacuating the building. This response is used by ambulatory surgery facility and assisted living facilities to protect the health and safety of fragile occupants and residents.
WALL, LOAD-BEARING. Any wall meeting either of the following classifications:
1. Any metal or wood stud wall that supports more than 100 pounds per linear foot (1459 N/m) of vertical load in addition to its own weight.
2. Any masonry or concrete, or mass timber wall that supports more than 200 pounds per linear foot (2919 N/m) of vertical load in addition to its own weight.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 21-12-103, § 51-50-0200, filed 6/2/21, effective 7/3/21; WSR 20-01-090, § 51-50-0200, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-0200, filed 12/26/18, effective 7/1/19; WSR 16-03-064, § 51-50-0200, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.074, 19.27.020, and 19.27.031. WSR 14-24-089, § 51-50-0200, filed 12/1/14, effective 5/1/15. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0200, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0200, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.190, 19.27.020, and chapters 19.27 and 34.05 RCW. WSR 08-01-110, § 51-50-0200, filed 12/18/07, effective 4/1/08. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0200, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074, and chapters 19.27 and 34.05 RCW. WSR 05-24-070, § 51-50-0200, filed 12/5/05, effective 7/1/06. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0200, filed 12/17/03, effective 7/1/04.]



PDF51-50-0303

Section 303Assembly Group A.

303.4 Assembly Group A-3. Group A-3 occupancy includes assembly uses intended for worship, recreation or amusement and other assembly uses not classified elsewhere in Group A including, but not limited to:
• Amusement arcades;
• Art galleries more than 3,000 square feet;
• Bowling alleys;
• Community halls;
• Courtrooms;
• Dance halls (not including food or drink consumption);
• Exhibition halls;
• Funeral parlors;
• Greenhouses for the conservation and exhibition of plants that provide public access;
• Gymnasiums (without spectator seating);
• Indoor swimming pools (without spectator seating);
• Indoor tennis courts (without spectator seating);
• Lecture halls;
• Libraries;
• Museums;
• Places of religious worship;
• Pool and billiard parlors;
• Waiting areas in transportation terminals.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0303, filed 12/12/19, effective 7/1/20.]



PDF51-50-0305

Section 305—Educational Group E.

305.2.4 Family home child care. Family home child care licensed by Washington state for the care of twelve or fewer children shall be classified as Group R-3 or shall comply with the International Residential Code.
[Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0305, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0305, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0305, filed 12/17/03, effective 7/1/04.]



PDF51-50-0306

Section 306Factory Group F.

306.2 Moderate-hazard factory industrial, Group F-1. Factory industrial uses that are not classified as factory industrial F-2 low hazard shall be classified as F-1 moderate hazard and shall include, but not be limited to, the following:
Aircraft (manufacturing, not to include repair)
Appliances
Athletic equipment
Automobiles and other motor vehicles
Bakeries
Beverages: Over 16 percent alcohol content
Bicycles
Boats
Brooms or brushes
Business machines
Cameras and photo equipment
Canvas or similar fabric
Carpets and rugs (includes cleaning)
Clothing
Construction and agricultural machinery
Disinfectants
Dry cleaning and dyeing
Electric generation plants
Electronics
Engines (including rebuilding)
Food processing establishments and commercial kitchens not associated with restaurants, cafeterias and similar dining facilities more than 2,500 square feet (232m2) in area
Furniture
Hemp products
Jute products
Laundries
Leather products
Machinery
Marijuana processing
Metals
Millwork (sash and door)
Motion pictures and television filming (without spectators)
Musical instruments
Optical goods
Paper mills or products
Photographic film
Plastic products
Printing or publishing
Recreational vehicles
Refuse incineration
Shoes
Soaps and detergents
Textiles
Tobacco
Trailers
Upholstering
Wood; distillation
Woodworking (cabinet)
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-0306, filed 1/19/16, effective 7/1/16.]



PDF51-50-0308

Section 308Institutional Group I.

308.1.1 Definitions. The following terms are defined in Chapter 2:
24-HOUR CARE.
Custodial Care.
Detoxification Facilities.
Foster Care Facilities.
HOSPICE CARE CENTER.
Hospitals and psychiatric hospitals.
Incapable of self-preservation.
Medical care.
Nursing homes.
308.2 Institutional Group I-1. Institutional Group I-1 occupancy shall include buildings, structures or portions thereof for more than sixteen persons, excluding staff, who reside on a twenty-four-hour basis in a supervised environment and receive custodial care. Buildings of Group I-1 shall be classified as one of the occupancy conditions specified in Section 308.2.1 or 308.2.2. This group shall include, but not be limited to, the following:
Alcohol and drug centers;
Assisted living facilities as licensed by Washington state under chapter 388-78A WAC;
Congregate care facilities;
Group homes;
Halfway houses;
Residential board and care facilities;
Social rehabilitation facilities;
Residential treatment facilities as licensed by Washington state under chapter 246-337 WAC.
308.2.5 Adult family homes. Adult family homes licensed by Washington state shall be classified as Group R-3 or shall comply with the International Residential Code.
308.2.6 Licensed care facilities. Assisted living facilities as licensed by Washington state under chapter 388-78A WAC shall be classified as Group I-1, Condition 2.
Residential treatment facilities licensed by Washington state under chapter 246-337 WAC shall be classified as one or more occupancy types in accordance with chapter 246-337 WAC.
308.3 Institutional Group I-2. Institutional Group I-2 occupancy shall include buildings and structures used for medical care on a 24-hour basis for more than five persons who are incapable of self-preservation. This group shall include, but not be limited to, the following:
Foster care facilities.
Detoxification facilities.
Hospice care centers.
Hospitals.
Nursing homes.
Psychiatric hospitals.
308.5.5 Family home child care. Family home child care licensed by Washington state for the care of twelve or fewer children shall be classified as Group R-3 or shall comply with the International Residential Code.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-21-021, § 51-50-0308, filed 10/9/20, effective 11/9/20; WSR 20-01-090, § 51-50-0308, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0308, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0308, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0308, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0308, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0308, filed 12/17/03, effective 7/1/04.]



PDF51-50-0309

Section 309Mercantile Group M.

309.1 Mercantile Group M. Mercantile Group M occupancy includes, among others, the use of a building or structure or a portion thereof for the display and sale of merchandise, and involves stocks of goods, wares or merchandise incidental to such purposes and accessible to the public. Mercantile occupancies shall include, but not be limited to, the following:
• Art galleries 3,000 square feet or less;
• Department stores;
• Drug stores;
• Markets;
• Greenhouses for display and sale of plants that provide public access;
• Motor fuel-dispensing facilities;
• Retail or wholesale stores;
• Sales rooms.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0309, filed 12/12/19, effective 7/1/20.]



PDF51-50-0310

Section 310Residential Group R.

310.3 Residential Group R-2. Residential occupancies containing sleeping units or more than two dwelling units where the occupants are primarily permanent in nature, including:
Apartment houses
Boarding houses (nontransient) with more than 16 occupants
Congregate living facilities (nontransient) with more than 16 occupants
Convents
Dormitories
Fraternities and sororities
Hotels (nontransient)
Live/work units
Monasteries
Motels (nontransient)
Vacation timeshare properties
310.4.3 Adult family homes, family home child care. Adult family homes and family home child care facilities that are within a single-family home are permitted to comply with the International Residential Code.
310.4.4 Foster family care homes. Foster family care homes licensed by Washington state are permitted to comply with the International Residential Code, as an accessory use to a dwelling, for six or fewer children including those of the resident family.
310.5 Residential Group R-4. R-4 classification is not adopted. Any reference in this code to R-4 does not apply.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 21-06-035, § 51-50-0310, filed 2/23/21, effective 3/26/21; WSR 16-03-064, § 51-50-0310, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0310, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0310, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.190, 19.27.020, and chapters 19.27 and 34.05 RCW. WSR 08-01-110, § 51-50-0310, filed 12/18/07, effective 4/1/08. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0310, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0310, filed 12/17/03, effective 7/1/04.]



PDF51-50-0312

Reserved.

[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0312, filed 12/12/19, effective 7/1/20; WSR 16-06-108 and 16-03-064, § 51-50-0312, filed 3/1/16 and 1/19/16, effective 7/1/16.]



PDF51-50-0403

Section 403High-rise buildings.

403.3.2 Water supply to required fire pumps. In all buildings that are more than 420 feet (128 m) in building height, and buildings of Type IV-A and IV-B that are more than 120 feet in building height, required fire pumps shall be supplied by connections to not fewer than two water mains located in different streets. Separate supply piping shall be provided between each connection to the water main and the pumps. Each connection and the supply piping between the connection and the pumps shall be sized to supply the flow and pressure required for the pumps to operate.
EXCEPTION:
Two connections to the same main shall be permitted provided that the main is valved such that an interruption can be isolated so that the water supply will continue without interruption through not fewer than one of the connections.
403.5.4 Smokeproof enclosures. Every required interior exit stairway serving floors more than 75 feet (22,860 mm) above the lowest level of fire department vehicle access shall be a smokeproof enclosure in accordance with Sections 909.20 and 1023.11. Where interior exit stairways and ramps are pressurized in accordance with Section 909.20.5, the smoke control pressurization system shall comply with the requirements specified in Section 909.6.3.
403.4.8.3 Standby power loads. The following are classified as standby power loads:
1. Ventilation and automatic fire detection equipment for smokeproof enclosures.
2. Elevators.
3. Where elevators are provided in a high-rise building for accessible means of egress, fire service access or occupant self-evacuation, the standby power system shall also comply with Sections 1009.4, 3007 or 3008, as applicable.
4. Sump pumps required by ASME A17.1 serving pit drains at the bottom of elevator hoistways of fire service access or occupant evacuation elevators.
405.7.2 Smokeproof enclosure. Every required stairway serving floor levels more than 30 feet (9144 mm) below the finished floor of its level of exit discharge shall comply with the requirements for a smokeproof enclosure as provided in Sections 909.20 and 1023.11. Where interior exit stairways and ramps are pressurized in accordance with Section 909.20.5, the smoke control pressurization system shall comply with the requirements specified in Section 909.6.3.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0403, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-0403, filed 12/26/18, effective 7/1/19; WSR 16-03-064, § 51-50-0403, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0403, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0403, filed 1/20/10, effective 7/1/10.]



PDF51-50-0406

Reserved.

[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0406, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0406, filed 12/19/06, effective 7/1/07.]



PDF51-50-0407

Section 407Group I-2.

407.4.4.3 Access to corridor. Movement from habitable rooms shall not require passage through more than three doors and 100 feet (30,480 mm) distance of travel within the suite.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0407, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0407, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0407, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0407, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0407, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074 and chapters 19.27 and 34.05 RCW. WSR 05-01-014, § 51-50-0407, filed 12/2/04, effective 7/1/05.]



PDF51-50-0412

Section 412Aircraft-related occupancies.

412.2.2.1 Stairways. Stairways in airport traffic control towers shall be in accordance with Section 1011. Exit stairways shall be smokeproof enclosures complying with one of the alternatives provided in Section 909.20. Where interior exit stairways and ramps are pressurized in accordance with Section 909.20.5, the smoke control pressurization system shall comply with the requirements specified in Section 909.6.3.
[F] 412.7.3 Means of egress. The means of egress from heliports, helipads and helistops shall comply with the provisions of Chapter 10. Landing areas located on buildings or structures shall have two or more means of egress. For landing areas less than 60 feet in length or less than 2,000 square feet (186 m2) in area, the second means of egress is permitted to be a fire escape, alternating tread device or ladder leading to the floor below. On Group I-2 roofs with heliports or helipads and helistops, rooftop structures enclosing exit stair enclosures or elevator shafts shall be enclosed with fire barriers and opening protectives that match the rating of their respective shaft enclosures below.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 21-06-035, § 51-50-0412, filed 2/23/21, effective 3/26/21; WSR 20-01-090, § 51-50-0412, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0412, filed 1/19/16, effective 7/1/16.]
Reviser's note: The brackets and enclosed material in the text of the above section occurred in the copy filed by the agency.



PDF51-50-0420

Section 420Groups I-1, R-1, R-2, R-3.

420.2 Separation walls. Walls separating dwelling units in the same building, walls separating sleeping units in the same building and walls separating dwelling or sleeping units from other occupancies contiguous to them in the same building shall be constructed as fire partitions in accordance with Section 708. Buildings containing multiple sleeping units with common use or central kitchens shall not be classified as a single dwelling.
EXCEPTIONS:
1. Where sleeping units include private bathrooms, walls between bedrooms and the associated private bathrooms are not required to be constructed as fire partitions.
 
2. Where sleeping units are constructed as suites, walls between bedrooms within the sleeping unit and the walls between the bedrooms and associated living spaces are not required to be constructed as fire partitions.
 
3. In Groups R-3 facilities, walls within the dwelling units or sleeping units are not required to be constructed as fire partitions.
 
4. Groups R-2 and I-1 arranged into residential sleeping suites containing a maximum of five sleeping residents. Separation between bedrooms, living areas and toilet rooms within these residential sleeping suites shall not be required.
 
5. Group I-1 sleeping areas arranged so that a dedicated staff member has direct observation over a multiple resident sleeping room, without intervening full height walls, shall not be required to provide fire partitions within the resident sleeping area.
420.11 Adult family homes. This section shall apply to all newly constructed adult family homes and all existing single-family homes being converted to adult family homes. This section shall not apply to those adult family homes licensed by the state of Washington department of social and health services prior to July 1, 2001.
420.11.1 Sleeping room classification. Each sleeping room in an adult family home shall be classified as one of the following:
1. Type S - Where the means of egress contains stairs, elevators or platform lifts.
2. Type NS1 - Where one means of egress is at grade level or a ramp constructed in accordance with Section 420.7.8 is provided.
3. Type NS2 - Where two means of egress are at grade level or ramps constructed in accordance with Section 420.7.8 are provided.
420.11.2 Types of locking devices and door activation. All bedrooms and bathroom doors shall be openable from the outside when locked.
Every closet door shall be readily openable from the inside.
Operable parts of door handles, pulls, latches, locks and other devices installed in adult family homes shall be operable with one hand and shall not require tight grasping, pinching, or twisting of the wrist. Pocket doors shall have graspable hardware available when in the closed or open position.
The force required to activate operable parts shall be 5.0 pounds (22.2 N) maximum. Required exit door(s) shall have no additional locking devices. Required exit door hardware shall unlock inside and outside mechanisms when exiting the building allowing reentry into the adult family home without the use of a key, tool or special knowledge.
420.11.3 Smoke and carbon monoxide alarm requirements. Alarms shall be installed in such a manner so that the detection device warning is audible from all areas of the dwelling upon activation of a single alarm.
420.11.4 Escape windows and doors. Every sleeping room shall be provided with emergency escape and rescue windows as required by Section 1030. No alternatives to the sill height such as steps, raised platforms or other devices placed by the openings will be approved as meeting this requirement.
420.11.5 Grab bar general requirements. Where facilities are designated for use by adult family home clients, grab bars for water closets, bathtubs and shower stalls shall be installed according to ICC A117.1.
420.11.6 Shower stalls. Where provided to meet the requirements for bathing facilities, the minimum size of shower stalls for an adult family home shall be 30 inches deep by 48 inches long.
420.12 Licensed care cooking facilities. In Group I-1, Condition 2 assisted living facilities licensed under chapter 388-78A WAC and residential treatment facilities licensed under chapter 246-337 WAC, rooms or spaces that contain a cooking facility with domestic cooking appliances shall be permitted to be open to the corridor where all of the following criteria are met:
1. The number of care recipients housed in the smoke compartment is not greater than 30.
2. The number of care recipients served by the cooking facility is not greater than 30.
3. Only one cooking facility area is permitted in a smoke compartment.
4. The types of domestic cooking appliances permitted are limited to ovens, cooktops, ranges, warmers and microwaves.
5. The corridor is a clearly identified space delineated by construction or floor pattern, material or color.
6. The space containing the domestic cooking facility shall be arranged so as not to obstruct access to the required exit.
7. A domestic cooking hood installed and constructed in accordance with Section 505 of the International Mechanical Code is provided over the cooktop or range.
8. The domestic cooking hood provided over the cooktop or range shall be equipped with an automatic fire-extinguishing system of a type recognized for protection of domestic cooking equipment. Preengineered automatic extinguishing systems shall be tested in accordance with UL 300A and listed and labeled for the intended application. The system shall be installed in accordance with this code, its listing and the manufacturer's instructions.
9. A manual actuation device for the hood suppression system shall be installed in accordance with Sections 904.12.1 and 904.12.2.
10. An interlock device shall be provided such that upon activation of the hood suppression system, the power or fuel supply to the cooktop or range will be turned off.
11. A shut-off for the fuel and electrical power supply to the cooking equipment shall be provided in a location that is accessible only to staff.
12. A timer shall be provided that automatically deactivates the cooking appliances within a period of not more than 120 minutes.
13. A portable fire extinguisher shall be installed in accordance with Section 906 of the International Fire Code.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0420, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0420, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0420, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0420, filed 1/20/10, effective 7/1/10.]



PDF51-50-0422

Section 422Ambulatory care facilities.

422.3.1 Means of egress. Where ambulatory care facilities require smoke compartmentation in accordance with Section 422.3, the fire safety evacuation plans provided in accordance with Section 1002.2 shall identify the building components necessary to support Sections 403 and 404 of the International Fire Code.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0422, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0422, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0422, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0422, filed 1/20/10, effective 7/1/10.]



PDF51-50-0427

Reserved.

[Statutory Authority: RCW 19.27.077, 19.27.031 and 19.27.074. WSR 21-14-074 and 21-16-063, § 51-50-0427, filed 7/6/21 and 7/29/21, effective 8/6/21 and 8/29/21. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-0427, filed 1/19/16, effective 7/1/16.]



PDF51-50-0429

Section 429Electric vehicle charging infrastructure.

429.1 Scope. The provisions of this section shall apply to the construction of new buildings.
EXCEPTIONS:
1. Occupancies classified as Group R-3 or Group U.
 
2. Group A, Group E, or Group M occupancies, except where employee parking spaces are designated. The provisions of Section 429 shall apply only to those designated employee parking spaces.
429.2 Required electric vehicle charging infrastructure. Where parking is provided, ten percent of parking spaces shall be provided with electric vehicle charging infrastructure in compliance with Sections 429.3, 429.4 and 429.5. When the calculation of percent served results in a fractional parking space, the applicant shall round up to the next whole number.
429.3 Electrical room(s). Electrical room(s) serving buildings with on-site parking spaces must be sized to accommodate the potential for electrical equipment and distribution required to serve a minimum of 20 percent of the total parking spaces with 208/240 V 40-amp, circuit or equivalent electric vehicle charging infrastructure.
429.4 Electric vehicle charging infrastructure. Electric vehicle charging infrastructure shall meet the following requirements:
1. A minimum number of 208/240 V 40-amp, circuit or equivalent electric vehicle charging stations required to serve the parking spaces specified in Section 429.2. The electric vehicle charging stations shall be located to serve spaces designated for parking and charging electric vehicles.
2. Additional service capacity, space for future meters, panel capacity or space for additional panels, and raceways for future installation of electric vehicle charging stations. The service capacity and raceway size shall be designed to accommodate the future installation of the number of 208/240 V 40-amp, circuit or equivalent electric vehicle charging stations specified in Section 429.2. The raceway shall terminate at spaces designated for parking and charging electric vehicles in the future.
Where designated electric vehicle charging locations serve exterior on-grade parking spaces that are located more than 4 feet from a building, raceways shall be extended below grade to a pull box in the vicinity of the designated future electric vehicle charging locations or stub above grade in the vicinity of the designated future electric vehicle charging locations, protected from vehicles by a curb or other device.
EXCEPTION:
In lieu of surface-mounted raceway between the electrical panel and the designated electric vehicle charging locations, it is permitted to provide permanent markings indicating the pathway for future raceway, and one-inch diameter capped sleeves through each wall and floor assembly that are penetrated along that route. This pathway and the locations of capped sleeves shall also be indicated on the electrical plans. Raceway shall be installed for any portion of the pathway located below slabs, below grade, or within floor, wall or roof assemblies.
Load management infrastructure may be used to adjust the size and capacity of the required building electric service equipment and circuits on the customer facilities, as well as electric utility owned infrastructure, as allowed by applicable local and national electric codes.
429.5 Electric vehicle charging infrastructure for accessible parking spaces. When electric vehicle charging infrastructure is required, ten percent of accessible parking space, rounded to the next whole number, shall be provided with electric vehicle charging infrastructure. The electric vehicle charging infrastructure may also serve adjacent parking spaces not designated as accessible parking. A maximum of ten percent rounded to the next whole number, of the accessible parking spaces are allowed to be included in the total number of electric vehicle parking spaces required under Section 429.2.
[Statutory Authority: RCW 19.27.077, 19.27.031 and 19.27.074. WSR 21-16-063, § 51-50-0429, filed 7/29/21, effective 8/29/21.]



PDF51-50-0502

Reserved.

[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0502, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0502, filed 12/19/06, effective 7/1/07.]



PDF51-50-0503

Section 503General building height and area limitations.

503.1.4 Occupied roofs. A roof level or portion thereof shall be permitted to be used as an occupied roof provided the occupancy of the roof is an occupancy that is permitted by Table 504.4 for the story immediately below the roof. The area of the occupied roofs shall not be included in the building area as regulated by Section 506.
EXCEPTIONS:
1. The occupancy located on an occupied roof shall not be limited to the occupancies allowed on the story immediately below the roof where the building is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2 and occupant notification in accordance with Sections 907.5.2.1 and 907.5.2.3 is provided in the area of the occupied roof. Emergency voice/alarm communication system notification in accordance with Section 907.5.2.2 shall also be provided in the area of the occupied roof where such system is required elsewhere in the building.
 
2. Assembly occupancies shall be permitted on roofs of open parking spaces of Type I or Type II construction, in accordance with the exception to Section 903.2.1.6.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0503, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0503, filed 1/19/16, effective 7/1/16.]



PDF51-50-0504

Section 504Building height and number of stories.

Table 504.3
Allowable Building Height in Feet Above Grade Planea
Occupancy Classification
Type of Construction
See
Footnotes
Type I
Type II
Type III
Type IV
Type V
A
B
A
B
A
B
A
B
C
HT
A
B
A, B, E, F, M, S, U
NSb
UL
160
65
55
65
55
65
65
65
65
50
40
S
UL
180
85
75
85
75
270
180
85
85
70
60
H-1, H-2, H-3, H-5
NSc,d
UL
160
65
55
65
55
120
90
65
65
50
40
S
 
 
 
 
 
 
 
 
 
 
 
 
H-4
NSc,d
UL
160
65
55
65
55
65
65
65
65
50
40
S
UL
180
85
75
85
75
140
100
85
85
70
60
I-1 Condition 1, I-3
NSd,e
UL
160
65
55
65
55
65
65
65
65
50
40
S
UL
180
85
75
85
75
180
120
85
85
70
60
I-1 Condition 2, I-2
NSd,e,f
UL
160
65
55
65
55
65
65
65
65
50
40
Si
UL
180
85
 
 
 
 
 
 
 
 
 
I-4
NSd,g
UL
160
65
55
65
55
65
65
65
65
50
40
S
UL
180
85
75
85
75
180
120
85
85
70
60
Rh
NSd
UL
160
65
55
65
55
65
65
65
65
50
40
S13D
60
60
60
60
60
60
60
60
60
60
50
40
S13R
60
60
60
60
60
60
60
60
60
60
60
60
S
UL
180
85
75
85
75
270
180
85
85
70
60
For SI: 1 foot = 304.8 mm.
UL = Unlimited; NS = Buildings not equipped throughout with an automatic sprinkler system; S = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2.
 
a
See Chapters 4 and 5 for specific exceptions to the allowable height in this chapter.
 
b
See Section 903.2 for the minimum thresholds for protection by an automatic sprinkler system for specific occupancies.
 
c
New Group H occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.5.
 
d
The NS value is only for use in evaluation of existing building height in accordance with the International Existing Building Code.
 
e
New Group I-1 and I-3 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6. For new Group I-1 occupancies Condition 1, see Exception 1 of Section 903.2.6.
 
f
New and existing Group I-2 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6 and Section 1103.5 of the International Fire Code.
 
g
For new Group I-4 occupancies, see Exceptions 2 and 3 of Section 903.2.6.
 
h
New Group R occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.8.
 
i
I-1, Condition 2 Assisted living facilities licensed in accordance with chapter 388-78A WAC and residential treatment facilities as licensed by Washington state under chapter 246-337 WAC shall be permitted to use the allowable height above grade plane for Group R-2 occupancies.
Table 504.4
Allowable Number of Stories Above Grade Planea,b
Occupancy Classification
Type of Construction
See
Footnotes
Type I
Type II
Type III
Type IV
Type V
A
B
A
B
A
B
A
B
C
HT
A
B
A-1
NS
UL
5
3
2
3
2
3
3
3
3
2
1
S
UL
6
4
3
4
3
9
6
4
4
3
2
A-2
NS
UL
11
3
2
3
2
3
3
3
3
2
1
S
UL
12
4
3
4
3
18
12
6
4
3
2
A-3
NS
UL
11
3
2
3
2
3
3
3
3
2
1
S
UL
12
4
3
4
3
18
12
6
4
3
2
A-4
NS
UL
11
3
2
3
2
3
3
3
3
2
1
S
UL
12
4
3
4
3
18
12
6
4
3
2
A-5
NS
UL
UL
UL
UL
UL
UL
1
1
1
UL
UL
UL
S
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
B
NS
UL
11
5
3
5
3
5
5
5
5
3
2
S
UL
12
6
4
6
4
18
12
9
6
4
3
E
NS
UL
5
3
2
3
2
3
3
3
3
1
1
S
UL
6
4
3
4
3
9
6
4
4
2
2
F-1
NS
UL
11
4
2
3
2
3
3
3
4
2
1
S
UL
12
5
3
4
3
10
7
5
5
3
2
F-2
NS
UL
11
5
3
4
3
5
5
5
5
3
2
S
UL
12
6
4
5
4
12
8
6
6
4
3
H-1
NSc,d
1
1
1
1
1
1
NP
NP
NP
1
1
NP
S
 
 
 
 
 
 
1
1
1
 
 
 
H-2
NSc,d
UL
3
2
1
2
1
1
1
1
2
1
1
S
 
 
 
 
 
 
2
2
2
 
 
 
H-3
NSc,d
UL
6
4
2
4
2
3
3
3
4
2
1
S
 
 
 
 
 
 
4
4
4
 
 
 
H-4
NSc,d
UL
7
5
3
5
3
5
5
5
5
3
2
S
UL
8
6
4
6
4
8
7
6
6
4
3
H-5
NSc,d
4
4
3
3
3
3
2
2
2
3
3
2
S
 
 
 
 
 
 
3
3
3
 
 
 
I-1 Condition 1
NSd,e
UL
9
4
3
4
3
4
4
4
4
3
2
S
UL
10
5
4
5
4
10
7
5
5
4
3
I-1 Condition 2
NSd,e
UL
9
4
3
4
3
3
3
3
4
3
2
Si
UL
10
5
 
 
 
10
6
4
 
 
 
I-2
NSd,f
UL
4
2
1
1
NP
NP
NP
NP
1
1
NP
S
UL
5
3
 
 
 
7
5
1
 
 
 
I-3
NSd,e
UL
4
2
1
2
1
2
2
2
2
2
1
S
UL
5
3
2
3
2
7
5
3
3
3
2
I-4
NSd,g
UL
5
3
2
3
2
3
3
3
3
1
1
S
UL
6
4
3
4
3
9
6
4
4
2
2
M
NS
UL
11
4
2
4
2
4
4
4
4
3
1
S
UL
12
5
3
5
3
12
8
6
5
4
2
R-1h
NSd
UL
11
4
4
4
4
4
4
4
4
3
2
S13R
4
4
 
 
 
 
 
 
 
 
4
3
S
UL
12
5
5
5
5
18
12
8
5
4
3
R-2h
NSd
UL
11
4
4
4
4
4
4
4
4
3
2
S13R
4
4
4
 
 
 
 
 
 
 
4
3
 
S
UL
12
5
5
5
5
18
12
8
5
4
3
R-3h
NSd
UL
11
4
4
4
4
4
4
4
4
3
3
S13D
4
4
 
 
 
 
 
 
 
 
3
3
S13R
4
4
 
 
 
 
 
 
 
 
4
4
S
UL
12
5
5
5
5
18
12
5
5
4
4
R-4h
NSd
UL
11
4
4
4
4
4
4
4
4
3
2
S13D
4
4
 
 
 
 
 
 
 
 
3
2
S13R
4
4
 
 
 
 
 
 
 
 
4
3
S
UL
12
5
5
5
5
18
12
5
5
4
3
S-1
NS
UL
11
4
2
3
2
4
4
4
4
3
1
S
UL
12
5
3
4
3
10
7
5
5
4
2
S-2
NS
UL
11
5
3
4
3
4
4
4
4
4
2
S
UL
12
6
4
5
4
12
8
5
5
5
3
U
NS
UL
5
4
2
3
2
4
4
4
4
2
1
S
UL
6
5
3
4
3
9
6
5
5
3
2
UL = Unlimited; NP = Not permitted; NS = Buildings not equipped throughout with an automatic sprinkler system; S = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2.
 
a
See Chapters 4 and 5 for specific exceptions to the allowable height in this chapter.
 
b
See Section 903.2 for the minimum thresholds for protection by an automatic sprinkler system for specific occupancies.
 
c
New Group H occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.5.
 
d
The NS value is only for use in evaluation of existing building height in accordance with the International Existing Building Code.
 
e
New Group I-1 and I-3 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6. For new Group I-1 occupancies Condition 1, see Exception 1 of Section 903.2.6.
 
f
New and existing Group I-2 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6 and Section 1103.5 of the International Fire Code.
 
g
For new Group I-4 occupancies, see Exceptions 2 and 3 of Section 903.2.6.
 
h
New Group R occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.8.
 
i
Group I-1, Condition 2 Assisted living facilities licensed in accordance with chapter 388-78A WAC and residential treatment facilities as licensed by Washington state under chapter 246-337 WAC shall be permitted to use the allowable number of stories for Group R-2 occupancies.
504.4.1 Stair enclosure pressurization increase. For Group R-1, R-2, and I-1 Condition 2 Assisted living facilities licensed under 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. Legally required standby power shall be provided in accordance with Sections 909.11 and 2702.2.16 for buildings constructed in compliance with this section and be connected to stairway shaft pressurization equipment, elevators and lifts used for accessible means of egress (if provided), elevator hoistway pressurization equipment (if provided) and other life safety equipment as determined by the authority having jurisdiction. For the purposes of this section, legally required standby power shall comply with 2020 NEC Section 701.12, options (C), (D), (E), (F), (H) or (J) or subsequent revised section number(s).
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 21-06-035, § 51-50-0504, filed 2/23/21, effective 3/26/21; WSR 20-21-021, § 51-50-0504, filed 10/9/20, effective 11/9/20; WSR 20-01-090, § 51-50-0504, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-0504, filed 12/26/18, effective 7/1/19; WSR 16-03-064, § 51-50-0504, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0504, filed 2/1/13, effective 7/1/13. Statutory Authority: Chapter 19.27 RCW. WSR 10-24-059, § 51-50-0504, filed 11/29/10, effective 7/1/11.]



PDF51-50-0505

Reserved.

[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0505, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0505, filed 1/19/16, effective 7/1/16.]



PDF51-50-0506

Section 506Building area.

Table 506.2
Allowable Area Factor (At = NS, S1, S13R, S13D or SM, as applicable) In Square Feeta,b
Occupancy Classification
See
Footnotes
Type of Construction
Type I
Type II
Type III
Type IV
Type V
A
B
A
B
A
B
A
B
C
HT
A
B
A-1
NS
UL
UL
15,500
8,500
14,000
8,500
45,000
30,000
18,750
15,000
11,500
5,500
S1
UL
UL
62,000
34,000
56,000
34,000
180,000
120,000
75,000
60,000
46,000
22,000
SM
UL
UL
46,500
25,500
42,000
25,500
135,000
90,000
56,250
45,000
34,500
16,500
A-2
NS
UL
UL
15,500
9,500
14,000
9,500
45,000
30,000
18,750
15,000
11,500
6,000
S1
UL
UL
62,000
38,000
56,000
38,000
180,000
120,000
75,000
60,000
46,000
24,000
SM
UL
UL
46,500
28,500
42,000
28,500
135,000
90,000
56,250
45,000
34,500
18,000
A-3
NS
UL
UL
15,500
9,500
14,000
9,500
45,000
30,000
18,750
15,000
11,500
6,000
S1
UL
UL
62,000
38,000
56,000
38,000
180,000
120,000
75,000
60,000
46,000
24,000
SM
UL
UL
46,500
28,500
42,000
28,500
135,000
90,000
56,250
45,000
34,500
18,000
A-4
NS
UL
UL
15,500
9,500
14,000
9,500
45,000
30,000
18,750
15,000
11,500
6,000
S1
UL
UL
62,000
38,000
56,000
38,000
180,000
120,000
75,000
60,000
46,000
24,000
SM
UL
UL
46,500
28,500
42,000
28,500
135,000
90,000
56,250
45,000
34,500
18,000
A-5
NS
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
S1
 
 
 
 
 
 
 
 
 
 
 
 
SM
 
 
 
 
 
 
 
 
 
 
 
 
B
NS
UL
UL
37,500
23,000
28,500
19,000
108,000
72,000
45,000
36,000
18,000
9,000
S1
UL
UL
150,000
92,000
114,000
76,000
432,000
288,000
180,000
144,000
72,000
36,000
SM
UL
UL
112,500
69,000
85,500
57,000
324,000
216,000
135,000
108,000
54,000
27,000
E
NS
UL
UL
26,500
14,500
23,500
14,500
76,500
51,000
31,875
25,500
18,500
9,500
S1
UL
UL
106,000
58,000
94,000
58,000
306,000
204,000
127,500
102,000
74,000
38,000
SM
UL
UL
79,500
43,500
70,500
43,500
229,500
153,000
95,625
76,500
55,500
28,500
F-1
NS
UL
UL
25,000
15,500
19,000
12,000
100,500
67,000
41,875
33,500
14,000
8,500
S1
UL
UL
100,000
62,000
76,000
48,000
402,000
268,000
167,500
134,000
56,000
34,000
SM
UL
UL
75,000
46,500
57,000
36,000
301,500
201,000
125,625
100,500
42,000
25,500
F-2
NS
UL
UL
37,500
23,000
28,500
18,000
151,500
101,000
63,125
50,500
21,000
13,000
S1
UL
UL
150,000
92,000
114,000
72,000
606,000
404,000
252,500
202,000
84,000
52,000
SM
UL
UL
112,500
69,000
85,500
54,000
454,500
303,000
189,375
151,500
63,000
39,000
H-1
NSc
21,000
16,500
11,000
7,000
9.500
7,000
10,500
10,500
10,000
10,500
7,500
NP
S1
 
 
 
 
 
 
 
 
 
 
 
 
H-2
NSc
21,000
16,500
11,000
7,000
9.500
7,000
10,500
10,500
10,000
10,500
7,500
3,000
S1
 
 
 
 
 
 
 
 
 
 
 
 
SM
 
 
 
 
 
 
 
 
 
 
 
 
H-3
NSc
UL
60,000
26,500
14,000
17,500
13,000
25,500
25,500
25,500
25,500
10,000
5,000
S1
 
 
 
 
 
 
 
 
 
 
 
 
SM
 
 
 
 
 
 
 
 
 
 
 
 
H-4
NSc,d
UL
UL
37,500
17,500
28,500
17,500
72,000
54,000
40,500
36,000
18,000
6,500
S1
UL
UL
150,000
70,000
114,000
70,000
288,000
216,000
162,000
144,000
72,000
26,000
SM
UL
UL
112,500
52,500
85,500
52,500
216,000
162,000
121,500
108,000
54,000
19,500
H-5
NSc,d
UL
UL
37,500
23,000
28,500
19,000
72,000
54,000
40,500
36,000
18,000
9,000
S1
UL
UL
150,000
92,000
114,000
76,000
288,000
216,000
162,000
144,000
72,000
36,000
SM
UL
UL
112,500
69,000
85,500
57,000
216,000
162,000
121,500
108,000
54,000
27,000
Occupancy Classification
See
Footnotes
Type of Construction
Type I
Type II
Type III
Type IV
Type V
A
B
A
B
A
B
A
B
C
HT
A
B
I-1
NSd, e
UL
55,000
19,000
10,000
16,500
10,000
54,000
36,000
18,000
18,000
10,500
4,500
S1
UL
220,000
76,000
40,000
66,000
40,000
216,000
144,000
72,000
72,000
42,000
18,000
SM
UL
165,000
57,000
30,000
49,500
30,000
162,000
108,000
54,000
54,000
31,500
13,500
I-2
NSd, f
UL
UL
15,000
11,000
12,000
NP
36,000
24,000
12,000
12,000
9,500
NP
S1
UL
UL
60,000
44,000
48,000
NP
144,000
96,000
48,000
48,000
38,000
NP
SM
UL
UL
45,000
33,000
36,000
NP
108,000
72,000
36,000
36,000
28,500
NP
I-3
NSd, e
UL
UL
15,000
10,000
10,500
7,500
36,000
24,000
12,000
12,000
7,500
5,000
S1
UL
UL
45,000
40,000
42,000
30,000
144,000
96,000
48,000
48,000
30,000
20,000
SM
UL
UL
45,000
30,000
31,500
22,500
108,000
72,000
36,000
36,000
22,500
15,000
I-4
NSd, g
UL
60.500
26,500
13,000
23,500
13,000
76,500
51,000
25,500
25,500
18,500
9,000
S1
UL
121,000
106,000
52,000
94,000
52,000
306,000
204,000
102,000
102,000
74,000
36,000
SM
UL
181,500
79,500
39,000
70,500
39,000
229,500
153,000
76,500
76,500
55,500
27,000
M
NS
UL
UL
21,500
12,500
18,500
12,500
61,500
41,000
25,625
20,500
14,000
9,000
S1
UL
UL
86,000
50,000
74,000
50,000
246,000
164,000
102,500
82,000
56,000
36,000
SM
UL
UL
64,500
37,500
55,500
37,500
184,500
123,000
76,875
61,500
42,000
27,000
R-1h
NSd
UL
UL
24,000
16,000
24,000
16,000
61,500
41,000
25,625
20,500
12,000
7,000
S13R
 
 
 
 
 
 
 
 
 
 
 
 
S1
UL
UL
96,000
64,000
96,000
64,000
246,000
164,000
102,500
82,000
48,000
28,000
SM
UL
UL
72,000
48,000
72,000
48,000
184,500
123,000
76,875
61,500
36,000
21,000
R-2h
NSd
UL
UL
24,000
16,000
24,000
16,000
61,500
41,000
25.625
20,500
12,000
7,000
S13R
S1
UL
UL
96,000
64,000
96,000
64,000
246,000
164,000
102,500
82,000
48,000
28,000
SM
UL
UL
72,000
48,000
72,000
48,000
184,500
123,000
76,875
61,500
36,000
21,000
R-3h
NSd
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
UL
S13D
 
 
 
 
 
 
 
 
 
 
 
 
S13R
 
 
 
 
 
 
 
 
 
 
 
 
S1
 
 
 
 
 
 
 
 
 
 
 
 
SM
 
 
 
 
 
 
 
 
 
 
 
 
R-4h
NSd
UL
UL
24,000
16,000
24,000
16,000
61,500
41,000
25,625
20,500
12,000
7,000
S13D
 
 
 
 
 
 
 
 
 
 
 
 
S13R
 
 
 
 
 
 
 
 
 
 
 
 
S1
UL
UL
96,000
64,000
96,000
64,000
246,000
164,000
102,500
82,000
48,000
28,000
SM
UL
UL
72,000
48,000
72,000
48,000
184,500
123,000
76,875
61,500
36,000
21,000
S-1
NS
UL
48,000
26,000
17,500
26,000
17,500
76,500
51,000
31,875
25,500
14,000
9,000
S1
UL
192,000
104,000
70,000
104,000
70,000
306,000
204,000
127,500
102,000
56,000
36,000
SM
UL
144,000
78,000
52,500
78,000
52,500
229,500
153,000
95,625
76,500
42,000
27,000
S-2
NS
UL
79,000
39,000
26,000
39,000
26,000
115,500
77,000
48,125
38,500
21,000
13,500
S1
UL
316,000
156,000
104,000
156,000
104,000
462,000
308,000
192,500
154,000
84,000
54,000
SM
UL
237,000
117,000
78,000
117,000
78,000
346,500
231,000
144,375
115,500
63,000
40,500
U
NSi
UL
35,500
19,000
8,500
14,000
8,500
54,000
36,000
22,500
18,000
9,000
5,500
S1
UL
142,000
76,000
34,000
56,000
34,000
216,000
144,000
90,000
72,000
36,000
22,000
SM
UL
106,500
57,000
25,500
42,000
25,500
162,000
108,000
67,500
54,000
27,000
16,500
For SI: 1 square foot = 0.0929 m2.
UL = Unlimited; NP = Not permitted; NS = Buildings not equipped throughout with an automatic sprinkler system; S1 = Buildings a maximum of one story above grade plane equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; SM = Buildings two or more stories above grade plane equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2; S13D = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.3.
 
a
See Chapters 4 and 5 for specific exceptions to the allowable height in this chapter.
 
b
See Section 903.2 for the minimum thresholds for protection by an automatic sprinkler system for specific occupancies.
 
c
New Group H occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.5.
 
d
The NS value is only for use in evaluation of existing building area in accordance with the International Existing Building Code.
 
e
New Group I-1 and I-3 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6. For new Group I-1 occupancies Condition 1, see Exception 1 of Section 903.2.6.
 
f
New and existing Group I-2 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6 and Section 1103.5 of the International Fire Code.
 
g
For new Group I-4 occupancies, see Exceptions 2 and 3 of Section 903.2.6.
 
h
New Group R occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.8.
 
i
The maximum allowable area for a single-story nonsprinklered Group U greenhouse is permitted to be 9,000 square feet, or the allowable area shall be permitted to comply with Table C102.1 of Appendix C.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0506, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-0506, filed 12/26/18, effective 7/1/19; WSR 16-03-064, § 51-50-0506, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0506, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0506, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0506, filed 12/19/06, effective 7/1/07.]



PDF51-50-0508

Section 508Mixed use and occupancy.

508.4.4.1 Construction. Required separations shall be fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 711, or both, so as to completely separate adjacent occupancies. Mass timber elements serving as fire barriers or horizontal assemblies to separate occupancies in Type IV-B or IV-C construction shall be separated from the interior of the building with an approved thermal barrier consisting of a minimum of 1/2 inch (12.7 mm) gypsum board or a material that is tested in accordance with and meets the acceptance criteria of both the Temperature Transmission Fire Test and the Integrity Fire Test of NFPA 275.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 19-02-038, § 51-50-0508, filed 12/26/18, effective 7/1/19.]



PDF51-50-0509

Section 509Incidental uses.

509.4.1.1 Type IV-B and IV-C construction. Where Table 509 specifies a fire-resistance-rated separation, mass timber elements serving as fire barriers or a horizontal assembly in Type IV-B or IV-C construction shall be separated from the interior of the incidental use with an approved thermal barrier consisting of a minimum of 1/2 inch (12.7 mm) gypsum board or a material that is tested in accordance with and meets the acceptance criteria of both the Temperature Transmission Fire Test and the Integrity Fire Test of NFPA 275.
Table 509
Incidental Uses
Room or Area
Separation and/or Protection
Dry type transformers over 112.5 kVA and required to be in a fire resistant room per NEC (NFPA 70) Section 450.21 (B)1
1 hour or provide automatic sprinkler system
1
Dry type transformers rated over 35,000 volts and oil-insulated transformers shall be installed in a transformer vault complying with NFPA 70.
(Remainder of table unchanged)
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 19-02-038, § 51-50-0509, filed 12/26/18, effective 7/1/19. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0509, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0509, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0509, filed 12/19/06, effective 7/1/07.]



PDF51-50-0510

Section 510Special provisions.

510.2 Horizontal building separation allowance. A building shall be considered as separate and distinct buildings for the purpose of determining area limitations, continuity of fire walls, limitation of number of stories and type of construction where all of the following conditions are met:
1. The buildings are separated with a horizontal assembly having a fire-resistance rating of not less than 3 hours where vertical offsets are provided as part of a horizontal assembly, the vertical offset and the structure supporting the vertical offset shall have a fire-resistance rating of not less than 3 hours.
2. The building below the horizontal assembly is of Type IA construction.
3. Shaft, stairway, ramp and escalator enclosures through the horizontal assembly shall have not less than a 2-hour fire-resistance rating with opening protective in accordance with Section 716.
EXCEPTION:
Where the enclosure walls below the horizontal assembly have not less than a 3-hour fire-resistance rating with opening protectives in accordance with Section 716, the enclosure walls extending above the horizontal assembly shall be permitted to have a 1-hour fire-resistance rating provided:
 
1. The building above the horizontal assembly is not required to be of Type I construction.
 
2. The enclosure connects fewer than four stories; and
 
3. The enclosure opening protective above the horizontal assembly have a fire protection rating of not less than 1 hour.
 
4. Interior exit stairways located within the Type IA building are permitted to be of combustible materials where both of the following requirements are met:
 
4.1. The building above the Type IA building is of Type III, IV, or V construction.
 
4.2. The stairway located in the Type IA building is enclosed by 3-hour fire-resistance-rated construction with opening protectives in accordance with Section 716.
4. The building or buildings above the horizontal assembly shall be permitted to have multiple Group A occupancy uses, each with an occupant load of less than 300, or Group B, Group I-1, Condition 2 licensed care facilities, M, R, or S occupancies.
5. The building below the horizontal assembly shall be protected throughout by an approved automatic sprinkler system in accordance with Section 903.3.1.1, and shall be permitted to be any occupancy allowed by this code except Group H.
6. The maximum building height in feet (mm) shall not exceed the limits set forth in Section 504.3 for the building having the smaller allowable height as measured from the grade plane. Group I-1, Condition 2 licensed care facilities shall be permitted to use the values for maximum height in feet for Group R-2 occupancies.
510.5 Group R-1 and R-2 buildings of Type IIIA construction. For buildings of Type IIIA construction in Groups R-1 and R-2, the maximum allowable height in Table 504.3 shall be increased by 10 feet and the maximum allowable number of stories in Table 504.4 shall be increased by one foot where the first floor assembly above the basement has a fire-resistance rating of not less than 3 hours and the floor area is subdivided by 2-hour fire-resistance-rated fire walls into areas of not more than 3,000 square feet (279 m2).
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-21-021, § 51-50-0510, filed 10/9/20, effective 11/9/20; WSR 20-01-090, § 51-50-0510, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0510, filed 1/19/16, effective 7/1/16.]



PDF51-50-0601

Section 601General.

Table 601
Fire-resistance Rating Requirements for Building Elements (hours)
Building Element
Type I
Type II
Type III
Type IV
Type V
A
B
A
B
A
B
A
B
C
HT
A
B
Primary structural framef (see Section 202)
3a
2a
1
0
1b
0
3a
2a
2a
HT
1
0
Bearing walls
 
 
 
 
 
 
 
 
 
 
 
 
Exteriore, f
3
2
1
0
2
2
3
2
2
2
1
0
Interior
3a
2a
1
0
1
0
3
2
2
1/HT
1
0
Nonbearing walls and partitions exterior
See Table 602
Nonbearing walls and partitions interiord
0
0
0
0
0
0
0
0
0
See Section 602.4.4.6
0
0
Floor construction and associated secondary members (see Section 202)
2
2
1
0
1
0
2
2
2
HT
1
0
Roof construction and associated secondary members (see Section 202)
1 1/2b
1b,c
1b,c
0c
1b,c
0
1 1/2
1
1
HT
1b,c
0
For SI: 1 foot = 304.8 mm.
 
a
Roof supports: Fire-resistance ratings of primary structural frame and bearing walls are permitted to be reduced by 1 hour where supporting a roof only.
 
b
Except in Groups F-1, H, M and S-1 occupancies, fire protection of structural members in roof construction shall not be required, including protection of primary structural frame members, roof framing and decking where every part of the roof construction is 20 feet or more above any floor immediately below. Fire-retardant-treated wood members shall be allowed to be used for such unprotected members.
 
c
In all occupancies, heavy timber complying with Section 2304.11 shall be allowed where a 1-hour or less fire-resistance rating is required.
 
d
Not less than the fire-resistance rating required by other sections of this code.
 
e
Not less than the fire-resistance rating based on fire separation distance (see Table 602).
 
f
Not less than the fire-resistance rating as referenced in Section 704.10.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 19-02-038, § 51-50-0601, filed 12/26/18, effective 7/1/19.]



PDF51-50-0602

Section 602Construction classification.

Table 602
Fire-resistance Rating Requirements for Exterior Walls Based on Fire Separation Distancea,d,g
Fire Separation Distance = X (feet)
Type of Construction
Occupancy Group He
Occupancy Group F-1, M, S-1f
Occupancy Group A, B, E, F-2, I, Ri,
S-2, Uh
X < 5b
All
3
2
1
5 ≤ X < 10
IA, IVA
3
2
1
 
Others
2
1
 
10 ≤ X < 30
IA, IB, IVA, IVB
2
1
1c
 
IIB, VB
1
0
0
 
Others
1
1
1c
X ≥ 30
All
0
0
0
For SI: 1 foot = 304.8 mm.
 
a
Load-bearing exterior walls shall also comply with the fire-resistance rating requirements of Table 601.
 
b
See Section 706.1.1 for party walls.
 
c
Open parking garages complying with Section 406 shall not be required to have a fire-resistance rating.
 
d
The fire-resistance rating of an exterior wall is determined based upon the fire separation distance of the exterior wall and the story in which the wall is located.
 
e
For special requirements for Group H occupancies, see Section 415.6.
 
f
For special requirements for Group S aircraft hangars, see Section 412.3.1.
 
g
Where Table 705.8 permits nonbearing exterior walls with unlimited area of unprotected openings, the required fire-resistance rating for the exterior walls is 0 hours.
 
h
For a building containing only a Group U occupancy private garage or carport, the exterior wall shall not be required to have a fire-resistance rating where the fire separation distance is 5 feet (1523 mm) or greater.
 
i
For a Group R-3 building of Type II-B or Type V-B construction, the exterior wall shall not be required to have a fire-resistance rating where the fire separation distance is 5 feet (1523 mm) or greater.
602.4 Type IV. Type IV construction is that type of construction in which the building elements are mass timber or noncombustible materials and have fire-resistance ratings in accordance with Table 601. Mass timber elements shall meet the fire-resistance rating requirements of this section based on either the fire-resistance rating of the noncombustible protection, the mass timber, or a combination of both and shall be determined in accordance with Section 703.2 or 703.3. The minimum dimensions and permitted materials for building elements shall comply with the provisions of this section including Section 2304.11. Mass timber elements of Types IV-A, IV-B and IV-C construction shall be protected with noncombustible protection applied directly to the mass timber in accordance with Sections 602.4.1 through 602.4.3. The time assigned to the noncombustible protection shall be determined in accordance with Section 703.8 and comply with 722.7.
Cross-laminated timber shall be labeled as conforming to ANSI/APA PRG 320 as referenced in Section 2303.1.4.
Exterior load-bearing walls and nonload-bearing walls shall be mass timber construction, or shall be of noncombustible construction.
EXCEPTION:
Exterior load-bearing walls and nonload-bearing walls of Type IV-HT Construction in accordance with Section 602.4.4.
The interior building elements, including nonload-bearing walls and partitions, shall be of mass timber construction or of noncombustible construction.
EXCEPTION:
Interior building elements and nonload-bearing walls and partitions of Type IV-HT Construction in accordance with Section 602.4.4.
Combustible concealed spaces are not permitted except as otherwise indicated in Sections 602.4.1 through 602.4.4. Combustible stud spaces within light frame walls of Type IV-HT construction shall not be considered concealed spaces, but shall comply with Section 718.
In buildings of Type IV-A, IV-B, and IV-C, construction with an occupied floor located more than 75 feet above the lowest level of fire department access, up to and including 12 stories or 180 feet above grade plane, mass timber interior exit and elevator hoistway enclosures shall be protected in accordance with Section 602.4.1.2. In buildings greater than 12 stories or 180 feet above grade plane, interior exit and elevator hoistway enclosures shall be constructed of noncombustible materials.
602.4.1 Type IV-A. Building elements in Type IV-A construction shall be protected in accordance with Sections 602.4.1.1 through 602.4.1.6. The required fire-resistance rating of noncombustible elements and protected mass timber elements shall be determined in accordance with Section 703.2 or Section 703.3.
602.4.1.1 Exterior protection. The outside face of exterior walls of mass timber construction shall be protected with noncombustible protection with a minimum assigned time of 40 minutes as determined in Section 722.7.1. All components of the exterior wall covering, shall be of noncombustible material except water resistive barriers having a peak heat release rate of less than 150 kW/m2, a total heat release of less than 20 MJ/m2 and an effective heat of combustion of less than 18 MJ/kg as determined in accordance with ASTM E1354 and having a flame spread index of 25 or less and a smoke-developed index of 450 or less as determined in accordance with ASTM E84 or UL 723. The ASTM E1354 test shall be conducted on specimens at the thickness intended for use, in the horizontal orientation and at an incident radiant heat flux of 50 kW/m2.
602.4.1.2 Interior protection. Interior faces of all mass timber elements, including the inside faces of exterior mass timber walls and mass timber roofs, shall be protected with materials complying with Section 703.5.
602.4.1.2.1 Protection time. Noncombustible protection shall contribute a time equal to or greater than times assigned in Table 722.7.1(1), but not less than 80 minutes. The use of materials and their respective protection contributions listed in Table 722.7.1(2), shall be permitted to be used for compliance with Section 722.7.1.
602.4.1.3 Floors. The floor assembly shall contain a noncombustible material not less than 1 inch in thickness above the mass timber. Floor finishes in accordance with Section 804 shall be permitted on top of the noncombustible material. The underside of floor assemblies shall be protected in accordance with 602.4.1.2.
602.4.1.4 Roofs. The interior surfaces of roof assemblies shall be protected in accordance with Section 602.4.1.2. Roof coverings in accordance with Chapter 15 shall be permitted on the outside surface of the roof assembly.
602.4.1.5 Concealed spaces. Concealed spaces shall not contain combustibles other than electrical, mechanical, fire protection, or plumbing materials and equipment permitted in plenums in accordance with Section 602 of the International Mechanical Code, and shall comply with all applicable provisions of Section 718. Combustible construction forming concealed spaces shall be protected in accordance with Section 602.4.1.2.
602.4.1.6 Shafts. Shafts shall be permitted in accordance with Sections 713 and 718. Both the shaft side and room side of mass timber elements shall be protected in accordance with Section 602.4.1.2.
602.4.2 Type IV-B. Building elements in Type IV-B construction shall be protected in accordance with Sections 602.4.2.1 through 602.4.2.6. The required fire-resistance rating of noncombustible elements or mass timber elements shall be determined in accordance with Section 703.2 or 703.3.
602.4.2.1 Exterior protection. The outside face of exterior walls of mass timber construction shall be protected with noncombustible protection with a minimum assigned time of 40 minutes as determined in Section 722.7.1. All components of the exterior wall covering shall be of noncombustible material except water resistive barriers having a peak heat release rate of less than 150 kW/m2, a total heat release of less than 20 MJ/m2 and an effective heat of combustion of less than 18 MJ/kg as determined in accordance with ASTM E1354, and having a flame spread index of 25 or less and a smoke-developed index of 450 or less as determined in accordance with ASTM E84 or UL 723. The ASTM E1354 test shall be conducted on specimens at the thickness intended for use, in the horizontal orientation and at an incident radiant heat flux of 50 kW/m2.
602.4.2.2 Interior protection. Interior faces of all mass timber elements, including the inside face of exterior mass timber walls and mass timber roofs, shall be protected, as required by this section, with materials complying with Section 703.5.
602.4.2.2.1 Protection time. Noncombustible protection shall contribute a time equal to or greater than times assigned in Table 722.7.1(1), but not less than 80 minutes. The use of materials and their respective protection contributions listed in Table 722.7.1(2), shall be permitted to be used for compliance with Section 722.7.1.
602.4.2.2.2 Protected area. All interior faces of all mass timber elements shall be protected in accordance with Section 602.4.2.2.1, including the inside face of exterior mass timber walls and mass timber roofs.
EXCEPTION:
Unprotected portions of mass timber ceilings and walls complying with Section 602.4.2.2.4 and the following:
 
1. Unprotected portions of mass timber ceilings, including attached beams, shall be permitted and shall be limited to an area equal to 20% of the floor area in any dwelling unit or fire area; or
 
2. Unprotected portions of mass timber walls, including attached columns, shall be permitted and shall be limited to an area equal to 40% of the floor area in any dwelling unit or fire area; or
 
3. Unprotected portions of both walls and ceilings of mass timber, including attached columns and beams, in any dwelling unit or fire area shall be permitted in accordance with Section 602.4.2.2.3.
 
4. Mass timber columns and beams which are not an integral portion of walls or ceilings, respectively, shall be permitted to be unprotected without restriction of either aggregate area or separation from one another.
602.4.2.2.3 Mixed unprotected areas. In each dwelling unit or fire area, where both portions of ceilings and portions of walls are unprotected, the total allowable unprotected area shall be determined in accordance with Equation 6-1.
(Equation 6-1)
(Utc/Uac) + (Utw/Uaw) ≤ 1
where:
 
Utc
=
Total unprotected mass timber ceiling areas;
 
Uac
=
Allowable unprotected mass timber ceiling area conforming to Section 602.4.2.2.2, Exception 1;
 
Utw
=
Total unprotected mass timber wall areas;
 
Uaw
=
Allowable unprotected mass timber wall area conforming to Section 602.4.2.2.2, Exception 2.
602.4.2.2.4 Separation distance between unprotected mass timber elements. In each dwelling unit or fire area, unprotected portions of mass timber walls and ceilings shall be not less than 15 feet from unprotected portions of other walls and ceilings, measured horizontally along the ceiling and from other unprotected portions of walls measured horizontally along the floor.
602.4.2.3 Floors. The floor assembly shall contain a noncombustible material not less than 1 inch in thickness above the mass timber. Floor finishes in accordance with Section 804 shall be permitted on top of the noncombustible material. The underside of floor assemblies shall be protected in accordance with Section 602.4.1.2.
602.4.2.4 Roofs. The interior surfaces of roof assemblies shall be protected in accordance with Section 602.4.2.2 except, in nonoccupiable spaces, they shall be treated as a concealed space with no portion left unprotected. Roof coverings in accordance with Chapter 15 shall be permitted on the outside surface of the roof assembly.
602.4.2.5 Concealed spaces. Concealed spaces shall not contain combustibles other than electrical, mechanical, fire protection, or plumbing materials and equipment permitted in plenums in accordance with Section 602 of the International Mechanical Code, and shall comply with all applicable provisions of Section 718. Combustible construction forming concealed spaces shall be protected in accordance with Section 602.4.1.2.
602.4.2.6 Shafts. Shafts shall be permitted in accordance with Sections 713 and 718. Both the shaft side and room side of mass timber elements shall be protected in accordance with Section 602.4.1.2.
602.4.3 Type IV-C. Building elements in Type IV-C construction shall be protected in accordance with Sections 602.4.3.1 through 602.4.3.6. The required fire-resistance rating of building elements shall be determined in accordance with Sections 703.2 or 703.3.
602.4.3.1 Exterior protection. The exterior side of walls of combustible construction shall be protected with noncombustible protection with a minimum assigned time of 40 minutes as determined in Section 722.7.1. All components of the exterior wall covering, shall be of noncombustible material except water resistive barriers having a peak heat release rate of less than 150 kW/m2, a total heat release of less than 20 MJ/m2 and an effective heat of combustion of less than 18 MJ/kg as determined in accordance with ASTM E1354 and having a flame spread index of 25 or less and a smoke-developed index of 450 or less as determined in accordance with ASTM E84 or UL 723. The ASTM E1354 test shall be conducted on specimens at the thickness intended for use, in the horizontal orientation and at an incident radiant heat flux of 50 kW/m2.
602.4.3.2 Interior protection. Mass timber elements are permitted to be unprotected.
602.4.3.3 Floors. Floor finishes in accordance with Section 804 shall be permitted on top of the floor construction.
602.4.3.4 Roofs. Roof coverings in accordance with Chapter 15 shall be permitted on the outside surface of the roof assembly.
602.4.3.5 Concealed spaces. Concealed spaces shall not contain combustibles other than electrical, mechanical, fire protection, or plumbing materials and equipment permitted in plenums in accordance with Section 602 of the International Mechanical Code, and shall comply with all applicable provisions of Section 718. Combustible construction forming concealed spaces shall be protected with noncombustible protection with a minimum assigned time of 40 minutes as determined in Section 722.7.1.
602.4.3.6 Shafts. Shafts shall be permitted in accordance with Sections 713 and 718. Shafts and elevator hoistway and interior exit stairway enclosures shall be protected with noncombustible protection with a minimum assigned time of 40 minutes as determined in Section 722.7.1, on both the inside of the shaft and the outside of the shaft.
602.4.4 Type IV-HT. Type IV-HT construction (Heavy Timber, HT) is that type of construction in which the exterior walls are of noncombustible materials and the interior building elements are of solid wood, laminated heavy timber or structural composite lumber (SCL), without concealed spaces. The minimum dimensions for permitted materials including solid timber, glued-laminated timber, structural composite lumber (SCL) and cross-laminated timber (CLT) and details of Type IV construction shall comply with the provisions of this section and Section 2304.11. Exterior walls complying with Section 602.4.4.1 or 602.4.4.2 shall be permitted. Interior walls and partitions not less than 1 hour fire-resistance rating or heavy timber conforming with Section 2304.11.2.2 shall be permitted.
602.4.4.1 Fire-retardant-treated wood in exterior walls. Fire-retardant-treated wood framing and sheathing complying with Section 2303.2 shall be permitted within exterior wall assemblies not less than 6 inches (152 mm) in thickness with a 2-hour rating or less.
602.4.4.2 Cross-laminated timber in exterior walls. Cross-laminated timber complying with Section 2303.1.4 shall be permitted within exterior wall assemblies not less than 6 inches (152 mm) in thickness with a 2-hour rating or less, provided the exterior surface of the cross-laminated timber is protected by one of the following:
1. Fire-retardant-treated wood sheathing complying with Section 2303.2 and not less than 15/32 inch (12 mm) thick;
2. Gypsum board not less than 1/2 inch (12.7 mm) thick; or
3. A noncombustible material.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-21-021, § 51-50-0602, filed 10/9/20, effective 11/9/20; WSR 20-01-090, § 51-50-0602, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-0602, filed 12/26/18, effective 7/1/19.]



PDF51-50-0603

Section 603Combustible material in Types I and II construction.

603.1 Allowable materials. Combustible materials shall be permitted in buildings of Type I or II construction in the following applications and in accordance with Sections 603.1.1 through 603.1.3:
1. Fire-retardant-treated wood shall be permitted in:
1.1. Nonbearing partitions where the required fire-resistance rating is 2 hours or less.
1.2. Nonbearing exterior walls where fire-resistance-rated construction is not required.
1.3. Roof construction, including girders, trusses, framing and decking.
EXCEPTION:
In buildings of Type I-A construction exceeding two stories above grade plane, fire-retardant-treated wood is not permitted in roof construction where the vertical distance from the upper floor to the roof is less than 20 feet (6096 mm).
1.4. Balconies, porches, decks and exterior stairways not used as required exits on buildings three stories or less above grade plane. Approved connector shall be in accordance with Section 2304.10.5.
2. Thermal and acoustical insulation, other than foam plastics, having a flame spread index of not more than 25.
EXCEPTIONS:
1. Insulation placed between two layers of noncombustible materials without an intervening airspace shall be allowed to have a flame spread index of not more than 100.
 
2. Insulation installed between a finished floor and solid decking without intervening airspace shall be allowed to have a flame spread index of not more than 200.
 
3. Foam plastics in accordance with Chapter 26.
 
4. Roof coverings that have an A, B or C classification.
 
5. Interior floor finish and floor covering materials installed in accordance with Section 804.
 
6. Millwork such as doors, door frames, window sashes and frames.
 
7. Interior wall and ceiling finishes installed in accordance with Section 803.
 
8. Trim installed in accordance with Section 806.
 
9. Where not installed greater than 15 feet (4572 mm) above grade, show windows, nailing or furring strips and wooden bulkheads below show windows, including their frames, aprons and show cases.
 
10. Finish flooring installed in accordance with Section 805.
 
11. Partitions dividing portions of stores, offices or similar places occupied by one tenant only and that do not establish a corridor serving an occupant load of 30 or more shall be permitted to be constructed of fire-retardant-treated wood, 1-hour fire-resistance-rated construction or of wood panels or similar light construction up to 6 feet (1829 mm) in height.
 
12. Stages and platforms constructed in accordance with Sections 410.2 and 410.3, respectively.
 
13. Combustible exterior wall coverings, balconies and similar projections and bay or oriel windows in accordance with Chapter 14 and Section 705.2.3.1.
 
14. Blocking such as for handrails, millwork, cabinets, and window and door frames.
 
15. Light-transmitting plastics as permitted by Chapter 26.
 
16. Mastics and caulking materials applied to provide flexible seals between components of exterior wall construction.
 
17. Exterior plastic veneer installed in accordance with Section 2605.2.
 
18. Nailing or furring strips as permitted by Section 803.15.
 
19. Heavy timber as permitted by Note c to Table 601 and Sections 602.4.3 and 705.2.3.1.
 
20. Aggregates, component materials and admixtures as permitted by Section 703.2.2.
 
21. Sprayed fire-resistant materials and intumescent and mastic fire-resistant coatings, determined on the basis of fire-resistance tests in accordance with Section 703.2 and installed in accordance with Sections 1705.14 and 1705.15, respectively.
 
22. Materials used to protect penetrations in fire-resistance-rated assemblies in accordance with Section 714.
 
23. Materials used to protect joints in fire-resistance-rated assemblies in accordance with Section 715.
 
24. Materials allowed in the concealed spaces of buildings of Types I and II construction in accordance with Section 718.5.
 
25. Materials exposed within plenums complying with Section 602 of the International Mechanical Code.
 
26. Wall construction of freezers and coolers of less than 1,000 square feet (92.9 m2), in size, lined on both sides with noncombustible materials and the building is protected throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-21-021, § 51-50-0603, filed 10/9/20, effective 11/9/20; WSR 20-01-090, § 51-50-0603, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-0603, filed 12/26/18, effective 7/1/19.]



PDF51-50-0703

Section 703Fire-resistance ratings and fire tests.

703.8 Determination of noncombustible protection time contribution. The time, in minutes, contributed to the fire-resistance rating by the noncombustible protection of mass timber building elements, components, or assemblies, shall be established through a comparison of assemblies tested using procedures set forth in ASTM E119 or UL 263. The test assemblies shall be identical in construction, loading, and materials, other than the noncombustible protection. The two test assemblies shall be tested to the same criteria of structural failure.
1. Test Assembly 1 shall be without protection.
2. Test Assembly 2 shall include the representative noncombustible protection. The protection shall be fully defined in terms of configuration details, attachment details, joint sealing details, accessories and all other relevant details.
The noncombustible protection time contribution shall be determined by subtracting the fire resistance time, in minutes, of Test Assembly 1 from the fire resistance time, in minutes, of Test Assembly 2.
703.9 Sealing of adjacent mass timber elements. In buildings of Type IV-A, IV-B, and IV-C construction, sealant or adhesive shall be provided to resist the passage of air in the following locations:
1. At abutting edges and intersections of mass timber building elements required to be fire-resistance-rated.
2. At abutting intersections of mass timber building elements and building elements of other materials where both are required to be fire-resistance-rated.
Sealants shall meet the requirements of ASTM C920. Adhesives shall meet the requirements of ASTM D3498.
EXCEPTION:
Sealants or adhesives need not be provided where a fire-resistance-rated assembly does not include them as a required component.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 19-02-038, § 51-50-0703, filed 12/26/18, effective 7/1/19.]



PDF51-50-0704

Section 704Fire-resistance rating of structural members.

704.6.1 Secondary (nonstructural) attachments to structural members. Where primary and secondary structural steel members require fire protection, secondary (nonstructural) tubular steel attachments to those structural members shall be protected with the same fire resistive rating as required for the structural member. The protection shall extend from the structural member a distance of not less than 12 inches. An open tubular attachment shall be filled with an equivalent fire protection method for a distance of 12-inch length from the structural member, or the entire length of the open tube, whichever is less.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0704, filed 12/12/19, effective 7/1/20.]



PDF51-50-0705

Section 705Exterior walls and projections.

705.1 General. Exterior walls and projections shall comply with this section.
705.2 Projections. Cornices, roof and eave overhangs, projecting floors above, exterior balconies and similar projections extending beyond the exterior wall shall conform to the requirements of this section and Section 1405. Exterior egress balconies and exterior exit stairways and ramps shall comply with Sections 1021 and 1027, respectively. Projections shall not extend any closer to the line used to determine the fire separation distance than shown in Table 705.2.
EXCEPTIONS:
1. Buildings on the same lot and considered as portions of one building in accordance with Section 705.3 are not required to comply with this section for projections between the buildings.
 
2. Projecting floors complying with Section 705.2.4 are not required to comply with the projection limitations of Table 705.2.
705.2.4 Projecting floors. Where the fire separation distance on a lower floor is greater than the fire separation distance on the floor immediately above, the projecting floor shall have not less than the fire-resistance rating as the exterior wall above based on Table 602. The fire-resistant rating of the horizontal portion shall be continuous to the lower vertical wall.
705.2.5 Bay and oriel windows. Bay and oriel windows constructed of combustible materials shall conform to the type of construction required for the building to which they are attached.
EXCEPTION:
Fire-retardant-treated wood shall be permitted on buildings three stories or less above grade plane of Type I, II, III or IV construction.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-21-021, § 51-50-0705, filed 10/9/20, effective 11/9/20; WSR 20-01-090, § 51-50-0705, filed 12/12/19, effective 7/1/20.]



PDF51-50-0706

Section 706Fire walls.

706.6.1 Stepped buildings. Where a fire wall also serves as an exterior wall for a building and separates buildings having different roof levels, such wall shall terminate at a point not less than 30 inches (762 mm) above the lower roof level. Exterior walls above the fire wall extending more than 30 inches above the lower roof shall be of not less than 1-hour fire-resistance-rated construction from both sides with openings protected by fire assemblies having a fire protection rating of not less than 3/4 hour. Portions of the exterior walls exceeding 15 feet above the lower roof shall be permitted to be of nonfire-resistance-rated construction unless otherwise required by other provisions of this code.
EXEMPTION:
A fire wall serving as part of an exterior wall that separates buildings having different roof levels shall be permitted to terminate at the underside of the roof sheathing, deck or slab of the lower roof, provided items 1, 2, and 3 below are met. The exterior wall above the fire wall is not required to be of fire-resistance-rated construction, unless required by other provisions of this code.
 
1. The lower roof assembly within 10 feet (3048 mm) of the fire wall has not less than a 1-hour fire-resistance rating.
 
2. The entire length and span of supporting elements for the rated roof assembly has a fire-resistance rating of not less than 1 hour.
 
3. Openings in the lower roof are not located within 10 feet (3048 mm) of the fire wall.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0706, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0706, filed 1/19/16, effective 7/1/16.]



PDF51-50-07070

Section 707Fire barriers.

707.4 Exterior walls. Where exterior walls serve as a part of a required fire-resistance-rated shaft or separation or enclosure for a stairway, ramp or exit passageway, such walls shall comply with the requirements of Section 705 for exterior walls and the fire-resistance-rated enclosure or separation requirements shall not apply.
EXCEPTION:
Exterior walls required to be fire-resistance-rated in accordance with Section 1021 for exterior egress balconies, Section 1023.7 for interior exit stairways and ramps, Section 1024.8 for exit passageways and Section 1027.6 for exterior exit stairways and ramp.
707.5 Continuity. Fire barriers shall extend from the top of the foundation or floor/ceiling assembly below to the underside of the floor or roof sheathing, slab or deck above and shall be securely attached thereto. Such fire barriers shall be continuous through concealed space, such as the space above a suspended ceiling. Joints and voids at intersections shall comply with Sections 707.8 and 707.9.
EXCEPTIONS:
1. Shaft enclosures shall be permitted to terminate at a top enclosure complying with Section 713.12.
 
2. Interior exit stairway and ramp enclosures required by Section 1023 and exit access stairway and ramp enclosures required by Section 1019 shall be permitted to terminate at a top enclosure complying with Section 713.12.
 
3. An exit passageway enclosure required by Section 1024.3 that does not extend to the underside of the roof sheathing, slab or deck above shall be enclosed at the top with construction of the same fire-resistance rating as required for the exit passageway.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-07070, filed 12/12/19, effective 7/1/20.]



PDF51-50-0708

Section 708—Reserved.

[Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0708, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, amended and recodified as § 51-50-0708, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0707, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0707, filed 12/17/03, effective 7/1/04.]



PDF51-50-0710

Section 710—Reserved.

[Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0710, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0710, filed 1/20/10, effective 7/1/10.]



PDF51-50-0713

Section 713Shaft enclosures.

713.13.4 Chute discharge room. Waste or linen chutes shall discharge into an enclosed room separated by fire barriers with a fire-resistance rating not less than the required fire rating of the shaft enclosure and constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 711, or both. Openings into the discharge room from the remainder of the building shall be protected by opening protectives having a fire-protection rating equal to the protection required for the shaft enclosure. Through penetrations of piping and conduit not necessary for the purpose of the chute discharge room are permitted as long as they are protected in accordance with Section 714 and do not impact the operation of the trash collection system. Doors shall be self- or automatic-closing upon the detection of smoke in accordance with Section 716.2.6.6. Waste chutes shall not terminate in an incinerator room. Waste and linen rooms that are not provided with chutes need only comply with Table 509.
713.13.7 Chute venting and roof termination. The full diameter of waste and linen chutes shall extend a minimum of 3 feet (0.92 m) above the building roof and be gravity vented in accordance with International Mechanical Code Section 515.
EXCEPTIONS:
1. Where mechanically ventilated in accordance with International Mechanical Code Section 515 the full diameter of the chute shall extend through the roof a minimum of 3 feet (0.92 m) and terminate at a blast cap. The mechanical exhaust connection shall tap into the side of the blast cap extension above the roof.
 
2. Where the trash chute does not extend to the upper floor of the building below the roof the trash chute shall be permitted to gravity vent to a sidewall louver termination. The horizontal extension of the trash chute shall be the full diameter of the chute and shall be enclosed in rated construction equal to the rating of the shaft enclosure. Where the chute is mechanically ventilated in accordance with International Mechanical Code Section 515 the blast cap shall terminate behind the louver and the exhaust fan and duct connection will be enclosed in the rated shaft.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0713, filed 12/12/19, effective 7/1/20.]



PDF51-50-0716

Section 716Opening protectives.

716.2.6.1 Door closing.Fire doors shall be latching and self- or automatic-closing in accordance with this section.
EXCEPTIONS:
1. Fire doors located in common walls separating sleeping units in Group R-l shall be permitted without automatic- or self-closing devices.
 
2. The elevator car doors and the associated hoistway enclosure doors at the floor level designated for recall in accordance with Section 3003.2 shall be permitted to remain open during Phase I emergency recall operation.
 
3. In Group I-1, Condition 2 Assisted living facilities licensed under chapter 388-78A WAC and residential treatment facilities licensed under chapter 246-337 WAC, fire doors in dwelling and sleeping units opening to the corridor shall be permitted without automatic or self-closing devices when all of the following conditions exist:
 
3.1 Each floor is constantly attended by staff on a 24-hour basis and stationed on that floor;
 
3.2 The facility is provided with an NFPA 13 sprinkler system throughout;
 
3.3 Doors shall be equipped with positive latching;
 
3.4 Dwelling and sleeping units are not equipped with cooking appliances;
 
3.5 Dwelling and sleeping units shall be equipped with a smoke detection system interconnected with the smoke detection system required by Section 907.2.6.1.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 21-06-035, § 51-50-0716, filed 2/23/21, effective 3/26/21; WSR 16-03-064, § 51-50-0716, filed 1/19/16, effective 7/1/16.]



PDF51-50-0717

Section 717Ducts and air transfer openings.

717.5.2 Fire barriers. Ducts and air transfer openings of fire barriers shall be protected with listed fire dampers installed in accordance with their listing. Ducts and air transfer openings shall not penetrate enclosures for interior exit stairways and ramps and exit passageways, except as permitted by Sections 1023.5 and 1024.6, respectively.
EXCEPTION:
Fire dampers are not required at penetrations of fire barriers where any of the following apply:
 
1. Penetrations are tested in accordance with ASTM E119 or UL 263 as part of the fire-resistance-rated assembly.
 
2. Ducts are used as part of an approved smoke control system in accordance with Section 909 and where the use of a fire damper would interfere with the operation of a smoke control system.
 
3. Such walls shall have a required fire-resistance rating of 1 hour or less, penetrated by ducted HVAC systems, in areas of other than Group H and are in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2. For the purposes of this exception, a ducted HVAC system shall be a duct system for conveying supply, return or exhaust air as part of the structure's HVAC system. Such a duct system shall be constructed of sheet steel not less than No. 26 gage thickness and shall be continuous without openings from the air-handling appliance or equipment to the air outlet and inlet terminals, located on the opposite side of the wall assembly.
717.5.4 Fire partitions. Ducts and air transfer openings that penetrate fire partitions shall be protected with listed fire dampers installed in accordance with their listing.
EXCEPTION:
In occupancies other than Group H, fire dampers are not required where any of the following apply:
 
1. Corridor walls in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2 and the duct is protected as a through penetration in accordance with Section 714.
 
2. Tenant partitions in covered and open mall buildings where the walls are not required by provisions elsewhere in the code to extend to the underside of the floor or roof sheathing, slab or deck above.
 
3. The duct system is constructed of approved materials in accordance with the International Mechanical Code and the duct penetrating the wall complies with all of the following requirements:
 
3.1. The duct shall not exceed 100 square inches (0.06 m2).
 
3.2. The duct shall be constructed of steel not less than 0.0217-inch (0.55 mm) in thickness.
 
3.3. The duct shall not have openings that communicate the corridor with adjacent spaces or rooms.
 
3.4. The duct shall be installed above a ceiling.
 
3.5. The duct shall not terminate at a wall register in the fire-resistance-rated wall.
 
3.6. A minimum 12-inch-long (305 mm) by 0.060-inch-thick (1.52 mm) steel sleeve shall be centered in each duct opening. The sleeve shall be secured to both sides of the wall and all four sides of the sleeve with minimum 1.5 inch by 1.5 inch by 0.060-inch (38 mm by 38 mm by 1.52 mm) steel retaining angles. The retaining angles shall be secured to the sleeve and the wall with No. 10 (M5) screws. The annular space between the steel sleeve and the wall opening shall be filled with mineral wool batting on all sides.
 
4. Such walls shall have a required fire-resistance rating of 1 hour or less, penetrated by ducted HVAC systems in areas of other than Group H and are in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2. For the purposes of this exception, a ducted HVAC system shall be a duct system for conveying supply, return or exhaust air as part of the structure's HVAC system. Such a duct system shall be constructed of sheet steel not less than No. 26 gage thickness and shall be continuous without openings from the air-handling appliance or equipment to the air outlet and inlet terminals located on the opposite side of the wall assembly.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0717, filed 12/12/19, effective 7/1/20.]



PDF51-50-0718

Section 718Concealed spaces.

718.2.1 Fireblocking materials.Fireblocking shall consist of the following materials:
1. Two inch (51 mm) nominal lumber.
2. Two thicknesses of 1 inch (25 mm) nominal lumber with broken lap joints.
3. One thickness of 0.719 inch (18.3 mm) wood structural panels with joints backed by 0.719 inch (18.3 mm) wood structural panels.
4. One thickness of 0.75 inch (19.1 mm) particleboard with joints backed by 0.75 inch (19 mm) particleboard.
5. One half inch (12.7 mm) gypsum board.
6. One fourth inch (6.4 mm) cement-based millboard.
7. Batts or blankets of mineral wool, mineral fiber or other approved materials installed in such a manner as to be securely retained in place.
8. Cellulose insulation installed as tested for the specific application.
9. Mass timber complying with Section 2304.11.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 19-02-038, § 51-50-0718, filed 12/26/18, effective 7/1/19.]



PDF51-50-0722

Section 722Calculated fire resistance.

722.7 Fire-resistance rating of mass timber. The required fire resistance of mass timber elements in Section 602.4 shall be determined in accordance with Section 703.2 or 703.3. The fire-resistance rating of building elements shall be as required in Tables 601 and 602 and as specified elsewhere in this code. The fire-resistance rating of the mass timber elements shall consist of the fire resistance of the unprotected element added to the protection time of the noncombustible protection.
722.7.1 Minimum required protection. When required by Sections 602.4.1 through 602.4.3, noncombustible protection shall be provided for mass timber building elements in accordance with Table 722.7.1(1). The rating, in minutes, contributed by the noncombustible protection of mass timber building elements, components, or assemblies, shall be established in accordance with Section 703.8. The protection contributions indicated in Table 722.7.1(2) shall be deemed to comply with this requirement when installed and fastened in accordance with Section 722.7.2.
Table 722.7.1(1)
Protection Required from Noncombustible Covering Material
Required Fire-Resistance Rating of Building Element per Tables 601 and 602 (hours)
Minimum Protection Required from Noncombustible Protection (minutes)
1
40
2
80
3 or more
120
Table 722.7.1(2)
Protection Provided by Noncombustible Covering Material
Noncombustible Protection
Protection Contribution (minutes)
1/2 inch Type X Gypsum board
25
5/8 inch Type X Gypsum board
40
722.7.2 Installation of gypsum board noncombustible protection. Gypsum board complying with Table 722.7.1(2) shall be installed in accordance with this section.
722.7.2.1 Interior surfaces. Layers of Type X gypsum board serving as noncombustible protection for interior surfaces of wall and ceiling assemblies determined in accordance with Table 722.7.1(1) shall be installed in accordance with the following:
1. Each layer shall be attached with Type S drywall screws of sufficient length to penetrate the mass timber at least 1 inch when driven flush with the paper surface of the gypsum board.
EXCEPTION:
The third layer, where determined necessary by Section 722.7, shall be permitted to be attached with 1 inch #6 Type S drywall screws to furring channels in accordance with ASTM C645.
2. Screws for attaching the base layer shall be 12 inches on center in both directions.
3. Screws for each layer after the base layer shall be 12 inches on center in both directions and offset from the screws of the previous layers by 4 inches in both directions.
4. All panel edges of any layer shall be offset 18 inches from those of the previous layer.
5. All panel edges shall be attached with screws sized and offset as in items 1 through 4 above and placed at least 1 inch but not more than 2 inches from the panel edge.
6. All panels installed at wall-to-ceiling intersections shall be installed such that the ceiling panel(s) is installed first and the wall panel(s) is installed after the ceiling panel has been installed and is fitted tight to the ceiling panel. Where multiple layers are required, each layer shall repeat this process.
7. All panels installed at a wall-to-wall intersection shall be installed such that the panel(s) covering an exterior wall or a wall with a greater fire-resistance rating shall be installed first and the panel(s) covering the other wall shall be fitted tight to the panel covering the first wall. Where multiple layers are required, each layer shall repeat this process.
8. Panel edges of the face layer shall be taped and finished with joint compound. Fastener heads shall be covered with joint compound.
9. Panel edges protecting mass timber elements adjacent to unprotected mass timber elements in accordance with Section 602.4.2.2 shall be covered with 1 1/4 inch metal corner bead and finished with joint compound.
722.7.2.2 Exterior surfaces. Layers of Type X gypsum board serving as noncombustible protection for the outside of the exterior heavy timber walls determined in accordance with Table 722.7.1(a) shall be fastened 12 inches on center each way and 6 inches on center at all joints or ends. All panel edges shall be attached with fasteners located at least 1 inch but not more than 2 inches from the panel edge. Fasteners shall comply with one of the following:
1. Galvanized nails of minimum 12 gage with a 7/16 inch head of sufficient length to penetrate the mass timber a minimum of 1 inch.
2. Screws that comply with ASTM C1002 (Type S, Type W, or Type G) of sufficient length to penetrate the mass timber a minimum of 1 inch.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 19-02-038, § 51-50-0722, filed 12/26/18, effective 7/1/19.]



PDF51-50-0803

Section 803Wall and ceiling finishes.

803.3 Heavy timber exemption. Exposed portions of building elements complying with the requirements for buildings of Type IV construction in Section 602.4 shall not be subject to interior finish requirements except in interior exit stairways, interior exit ramps, and exit passageways.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 19-02-038, § 51-50-0803, filed 12/26/18, effective 7/1/19.]



PDF51-50-0902

Section 902—Reserved.

[Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0902, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0902, filed 12/17/03, effective 7/1/04.]



PDF51-50-0903

Section 903Automatic sprinkler systems.

903.2.1.8 Nightclub. An automatic sprinkler system shall be provided throughout Group A-2 nightclubs as defined in this code.
903.2.3 Group E. An automatic sprinkler system shall be provided for fire areas containing Group E occupancies where the fire area has an occupant load of 51 or more, calculated in accordance with Table 1004.1.2.
EXCEPTIONS:
1. Portable school classrooms with an occupant load of 50 or less calculated in accordance with Table 1004.1.2, provided that the aggregate area of any cluster of portable school classrooms does not exceed 6,000 square feet (557 m2); and clusters of portable school classrooms shall be separated as required by the building code; or
 
2. Portable school classrooms with an occupant load from 51 through 98, calculated in accordance with Table 1004.1.2, and provided with two means of direct independent exterior egress from each classroom in accordance with Chapter 10, and one exit from each class room shall be accessible, provided that the aggregate area of any cluster of portable classrooms does not exceed 6,000 square feet (557 m2); and clusters of portable school classrooms shall be separated as required by the building code; or
 
3. Fire areas containing day care and preschool facilities with a total occupant load of 100 or less located at the level of exit discharge where every room in which care is provided has not fewer than one exit discharge door.
903.2.6 Group I. An automatic sprinkler system shall be provided throughout buildings with a Group I fire area.
EXCEPTIONS:
1. An automatic sprinkler system installed in accordance with Section 903.3.1.2 shall be permitted in Group I-1 Condition 1 facilities.
 
2. Where new construction house sixteen persons receiving care, an automatic sprinkler system installed in accordance with Section 903.3.1.2 shall be permitted for Group I-1, Condition 2, assisted living facilities licensed under chapter 388-78A WAC and residential treatment facilities licensed under chapter 246-337 WAC.
 
3. An automatic sprinkler system installed in accordance with Section 903.3.1.2 shall be permitted in additions to existing buildings where both of the following situations are true:
 
3.1. The addition is made to a building previously approved as Group LC or Group R-2 that houses either an assisted living facility licensed under chapter 388-78A WAC or residential treatment facility licensed under chapter 246-337 WAC.
 
3.2. The addition contains spaces for sixteen or fewer persons receiving care.
903.2.6.1 Group I-4. An automatic sprinkler system shall be provided in fire areas containing Group I-4 occupancies where the fire area has an occupant load of 51 or more, calculated in accordance with Table 1004.1.2.
EXCEPTIONS:
1. An automatic sprinkler system is not required for Group I-4 day care facilities with a total occupant load of 100 or less, and located at the level of exit discharge and where every room where care is provided has not fewer than one exterior exit door.
 
2. In buildings where Group I-4 day care is provided on levels other than the level of exit discharge, an automatic sprinkler system in accordance with Section 903.3.1.1 shall be installed on the entire floor where care is provided, all floors between the level of care and the level of exit discharge and all floors below the level of exit discharge other than areas classified as an open parking garage.
903.2.7 Group M. An automatic sprinkler system shall be provided throughout buildings containing a Group M occupancy, where one of the following conditions exists:
1. A Group M fire area exceeds 12,000 square feet (1115 m2).
2. A Group M fire area is located more than three stories above grade plane.
3. The combined area of all Group M fire areas on all floors, including any mezzanines, exceeds 24,000 square feet (2230 m2).
4. Where a Group M occupancy that is used for the display and sale of upholstered furniture or mattresses exceeds 5000 square feet (464 m2).
903.2.8 Group R. An automatic fire sprinkler system installed in accordance with Section 903.3 shall be provided throughout all buildings with a Group R fire area.
EXCEPTION:
Group R-1 if all of the following conditions apply:
 
1. The Group R fire area is no more than 500 square feet and is used for recreational use only.
 
2. The Group R fire area is only one story.
 
3. The Group R fire area does not include a basement.
 
4. The Group R fire area is no closer than 30 feet from another structure.
 
5. Cooking is not allowed within the Group R fire area.
 
6. The Group R fire area has an occupant load of no more than 8.
 
7. A hand held (portable) fire extinguisher is in every Group R fire area.
903.2.9.3 Group S-1 upholstered furniture and mattresses. An automatic sprinkler system shall be provided throughout a Group 5-1 fire area where the area used for storage of upholstered furniture exceeds 2,500 square feet (232 m2).
EXCEPTION:
Self-service storage facilities no greater than one story above grade plane where all storage spaces can be accessed directly from the exterior.
903.2.11 Specific building areas and hazards. In all occupancies other than Group U, an automatic sprinkler system shall be installed for building design or hazards in the locations set forth in Sections 903.2.11.1 through 903.2.11.7.
903.2.11.7 Relocatable buildings within buildings. Relocatable buildings or structures located within a building with an approved fire sprinkler system shall be provided with fire sprinkler protection within the occupiable space of the building and the space underneath the relocatable building.
EXCEPTIONS:
1. Sprinkler protection is not required underneath the building when the space is separated from the adjacent space by construction resisting the passage of smoke and heat and combustible storage will not be located there.
 
2. If the building or structure does not have a roof or ceiling obstructing the overhead sprinklers.
 
3. Construction trailers and temporary offices used during new building construction prior to occupancy.
 
4. Movable shopping mall kiosks with a roof or canopy dimension of less than 4 feet on the smallest side.
903.3.5.3 Underground portions of fire protection system water supply piping. The installation or modification of an underground water main, public or private, supplying a water-based fire protection system shall be in accordance with NFPA 24 and chapter 18.160 RCW. Piping and appurtenances downstream of the first control valve on the lateral or service line from the distribution main to one-foot above finished floor shall be approved by the fire code official. Such underground piping shall be installed by a fire sprinkler system contractor licensed in accordance with chapter 18.160 RCW and holding either a Level U or a Level 3 license. For underground piping supplying systems installed in accordance with Section 903.3.1.2, a Level 2, 3, or U licensed contractor is acceptable.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-21-021, § 51-50-0903, filed 10/9/20, effective 11/9/20; WSR 20-01-090, § 51-50-0903, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0903, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.074, 19.27.020, and 19.27.031. WSR 14-24-089, § 51-50-0903, filed 12/1/14, effective 5/1/15. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0903, filed 2/1/13, effective 7/1/13. Statutory Authority: Chapter 19.27 RCW. WSR 10-24-059, § 51-50-0903, filed 11/29/10, effective 7/1/11. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0903, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.190, 19.27.020, and chapters 19.27 and 34.05 RCW. WSR 08-01-110, § 51-50-0903, filed 12/18/07, effective 4/1/08. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0903, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074, and chapters 19.27 and 34.05 RCW. WSR 05-24-070, § 51-50-0903, filed 12/5/05, effective 7/1/06. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0903, filed 12/17/03, effective 7/1/04.]



PDF51-50-0907

Section 907Fire alarm and detection systems.

[F] 907.2.3 Group E. Group E occupancies shall be provided with a manual fire alarm system that initiates the occupant notification signal utilizing one of the following:
1. An emergency voice/alarm communication system meeting the requirements of Section 907.5.2.2 and installed in accordance with Section 907.6; or
2. A system developed as part of a safe school plan adopted in accordance with RCW 28A.320.125 or developed as part of an emergency response system consistent with the provisions of RCW 28A.320.126. The system must achieve all of the following performance standards:
2.1 The ability to broadcast voice messages or customized announcements;
2.2 Includes a feature for multiple sounds, including sounds to initiate a lock down;
2.3 The ability to deliver messages to the interior of a building, areas outside of a building as designated pursuant to the safe school plan, and to personnel;
2.4 The ability for two-way communications;
2.5 The ability for individual room calling;
2.6 The ability for a manual override;
2.7 Installation in accordance with NFPA 72;
2.8 Provide 15 minutes of battery backup for alarm and 24 hours of battery backup for standby; and
2.9 Includes a program for annual inspection and maintenance in accordance with NFPA 72.
EXCEPTIONS:
1. A manual fire alarm system is not required in Group E occupancies with an occupant load of 50 or less.
 
2. Emergency voice/alarm communication systems meeting the requirements of Section 907.5.2.2 and installed in accordance with Section 907.6 shall not be required in Group E occupancies with occupant loads of 100 or less, such as individual portable school classroom buildings; provided that activation of the manual fire alarm system initiates an approved occupant notification signal in accordance with Section 907.5.
 
3. Where an existing approved alarm system is in place, an emergency voice/alarm system is not required in any portion of an existing Group E building undergoing any one of the following repairs, alteration or addition:
 
3.1 Alteration or repair to an existing building including, without limitation, alterations to rooms and systems, and/or corridor configurations, not exceeding 35 percent of the fire area of the building (or the fire area undergoing the alteration or repair if the building is comprised of two or more fire areas); or
 
3.2 An addition to an existing building, not exceeding 35 percent of the fire area of the building (or the fire area to which the addition is made if the building is comprised of two or more fire areas).
 
4. Manual fire alarm boxes are not required in Group E occupancies where all of the following apply:
 
4.1 Interior corridors are protected by smoke detectors.
 
4.2 Auditoriums, cafeterias, gymnasiums and similar areas are protected by heat detectors or other approved detection devices.
 
4.3 Shops and laboratories involving dust or vapors are protected by heat detectors or other approved detection devices.
 
5. Manual fire alarm boxes shall not be required in Group E occupancies where all of the following apply:
 
5.1 The building is equipped throughout with an approved automatic sprinkler system installed in accordance with Section 903.3.1.1.
 
5.2 The emergency voice/alarm communication system will activate on sprinkler waterflow.
 
5.3 Manual activation is provided from a normally occupied location.
[F] 907.2.3.1 Sprinkler systems or detection. When automatic sprinkler systems or smoke detectors are installed, such systems or detectors shall be connected to the building fire alarm system.
[F] 907.2.6.4 Group I-4 occupancies. A manual fire alarm system that initiates the occupant notification signal utilizing an emergency voice/alarm communication system meeting the requirements of Section 907.5.2.2 and installed in accordance with Section 907.6 shall be installed in Group I-4 occupancies. When automatic sprinkler systems or smoke detectors are installed, such systems or detectors shall be connected to the building fire alarm system.
EXCEPTIONS:
1. A manual fire alarm system is not required in Group I-4 occupancies with an occupant load of 50 or less.
 
2. Emergency voice alarm communication systems meeting the requirements of Section 907.5.2.2 and installed in accordance with Section 907.6 shall not be required in Group I-4 occupancies with occupant loads of 100 or less, provided that activation of the manual fire alarm system initiates an approved occupant notification signal in accordance with Section 907.5.
[F] 907.5.2.1.2 Maximum sound pressure. The maximum sound pressure level for audible alarm notification appliances shall be 110 dBA at the minimum hearing distance from the audible appliance. For systems operating in public mode, the maximum sound pressure level shall not exceed 30 dBA over the average ambient sound level. Where the average ambient noise is greater than 95 dBA, visible alarm notification appliances shall be provided in accordance with NFPA 72 and audible alarm notification appliances shall not be required.
[F] 907.10 NICET: National Institute for Certification in Engineering Technologies.
907.10.1 Scope. This section shall apply to new and existing fire alarm systems.
907.10.2 Design review. All construction documents shall be reviewed by a NICET III in fire alarms or a licensed professional engineer (PE) in Washington prior to being submitted for permitting. The reviewing professional shall submit a stamped, signed, and dated letter; or a verification method approved by the local authority having jurisdiction indicating the system has been reviewed and meets or exceeds the design requirements of the state of Washington and the local jurisdiction. (Effective July 1, 2018.)
907.10.3 Testing/maintenance. All inspection, testing, maintenance and programing not defined as "electrical construction trade" by chapter 19.28 RCW shall be completed by a NICET II in fire alarms. (Effective July 1, 2018.)
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0907, filed 12/12/19, effective 7/1/20. Statutory Authority: RCW 19.27.074 and 19.27.550. WSR 18-01-104, § 51-50-0907, filed 12/19/17, effective 7/1/18. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-0907, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.074 and 19.27.530. WSR 12-01-099, § 51-50-0907, filed 12/20/11, effective 4/1/12. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0907, filed 1/20/10, effective 7/1/10.]
Reviser's note: The brackets and enclosed material in the text of the above section occurred in the copy filed by the agency.



PDF51-50-0908

Section 908Reserved.

[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-0908, filed 1/19/16, effective 7/1/16. Statutory Authority: Chapters 19.27A, 19.27, and 34.05 RCW. WSR 13-23-087, § 51-50-0908, filed 11/19/13, effective 4/1/14. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0908, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.074 and 19.27.530. WSR 12-01-099, § 51-50-0908, filed 12/20/11, effective 4/1/12.]



PDF51-50-0909

Section 909Smoke control systems.

909.21.12 Hoistway venting. Hoistway venting need not be provided for pressurized elevator shafts.
909.21.13 Machine rooms. Elevator machine rooms shall be pressurized in accordance with this section unless separated from the hoistway shaft by construction in accordance with Section 707.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-21-021, § 51-50-0909, filed 10/9/20, effective 11/9/20; WSR 20-01-090, § 51-50-0909, filed 12/12/19, effective 7/1/20; WSR 16-03-064, § 51-50-0909, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-0909, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-097, § 51-50-0909, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.074, 19.27.020, and chapters 70.92, 19.27, and 34.05 RCW. WSR 07-01-091, § 51-50-0909, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.020, 19.27.031, 19.27.074, and chapters 19.27 and 34.05 RCW. WSR 05-24-070, § 51-50-0909, filed 12/5/05, effective 7/1/06. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 04-01-108, § 51-50-0909, filed 12/17/03, effective 7/1/04.]



PDF51-50-0911

Section 911Reserved.

[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-0911, filed 1/19/16, effective 7/1/16; WSR 10-03-097, § 51-50-0911, filed 1/20/10, effective 7/1/10.]



PDF51-50-0913

Section 913Fire pumps.

913.2.1 Protection of fire pump rooms and access. Fire pumps shall be located in rooms that are separated from all other areas of the building by 2-hour fire barriers constructed in accordance with Section 707 or 2-hour horizontal assemblies constructed in accordance with Section 711, or both. Fire pump rooms not directly accessible from the outside shall be accessible through an enclosed passageway from an interior exit stairway or exterior exit. The enclosed passageway shall have a fire-resistance rating not less than the fire-resistance rating of the fire pump room (see NFPA 20 Section 4.12.2.1.2).
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-0913, filed 12/12/19, effective 7/1/20.]



PDF51-50-0915

Section 915Carbon monoxide detection.

915.1 General. Carbon monoxide detection shall be installed in new buildings in accordance with Sections 915.1.1 through 915.6. Carbon monoxide detection shall be installed in existing buildings in accordance with Chapter 11 of the International Fire Code.
915.1.1 Where required. Carbon monoxide detection shall be provided in Group I and R occupancies and in classrooms in Group E occupancies in the locations specified in Section 915.2 where any of the conditions in Sections 915.1.2 through 915.1.6 exist.
EXCEPTIONS:
1. R-2 occupancies, with the exception of R-2 college dormitories, are required to install carbon monoxide detectors without exception.
 
2. Sleeping units or dwelling units in I and R-1 occupancies and R-2 college dormitories, hotel, DOC prisons and work releases and DSHS licensed boarding home and residential treatment facility occupancies which do not themselves contain a fuel-burning appliance, a fuel-burning fireplace, or have an attached garage, need not be provided with carbon monoxide alarms provided that they comply with the exceptions of 915.1.4.
915.1.2 Fuel-burning appliances and fuel-burning fireplaces. Carbon monoxide detection shall be provided in dwelling units, sleeping units and classrooms that contain a fuel-burning appliance or a fuel-burning fireplace.
915.1.3 Forced-air furnaces. Carbon monoxide detection shall be provided in dwelling units, sleeping units and classrooms served by a fuel-burning, forced-air furnace.
EXCEPTION:
Carbon monoxide detection shall not be required in dwelling units, sleeping units and classrooms where carbon monoxide detection is provided in the first room or area served by each main duct leaving the furnace, and the carbon monoxide alarm signals are automatically transmitted to an approved location.
915.1.4 Fuel-burning appliances outside of dwelling units, sleeping units and classrooms. Carbon monoxide detection shall be provided in dwelling units, sleeping units and classrooms located in buildings that contain fuel-burning appliances or fuel-burning fireplaces.
EXCEPTIONS:
1. Carbon monoxide detection shall not be required in dwelling units, sleeping units and classrooms where there are no communicating openings between the fuel-burning appliance or fuel-burning fireplace and the dwelling unit, sleeping unit or classroom.
 
2. Carbon monoxide detection shall not be required in dwelling units, sleeping units and classrooms where carbon monoxide detection is provided in one of the following locations:
 
2.1. In an approved location between the fuel-burning appliance or fuel-burning fireplace and the dwelling unit, sleeping unit or classroom.
 
2.2. On the ceiling of the room containing the fuel-burning appliance or fuel-burning fireplace.
915.1.5 Private garages. Carbon monoxide detection shall be provided in dwelling units, sleeping units and classrooms in buildings with attached private garages.
EXCEPTIONS:
1. Carbon monoxide detection shall not be required where there are no communicating openings between the private garage and the dwelling unit, sleeping unit or classroom.
 
2. Carbon monoxide detection shall not be required in dwelling units, sleeping units and classrooms located more than one story above or below a private garage.
 
3. Carbon monoxide detection shall not be required where the private garage connects to the building through an open-ended corridor.
 
4. Where carbon monoxide detection is provided in an approved location between openings to a private garage and dwelling units, sleeping units or classrooms, carbon monoxide detection shall not be required in the dwelling units, sleeping units or classrooms.
915.1.6 Exempt garages. For determining compliance with Section 915.1.5, an open parking garage complying with Section 406.5 of the International Building Code or an enclosed parking garage complying with Section 406.6 of the International Building Code shall not be considered a private garage.
915.2 Locations. Where required by Section 915.1.1, carbon monoxide detection shall be installed in the locations specified in Sections 915.2.1 through 915.2.3.
915.2.1 Dwelling units. Carbon monoxide detection shall be installed in dwelling units outside of each separate sleeping area in the immediate vicinity of the bedrooms and on each level of the dwelling. Where a fuel-burning appliance or fuel-burning fireplace is located within a bedroom or its attached bathroom, carbon monoxide detection shall be installed within the bedroom.
915.2.2 Sleeping units. Carbon monoxide detection shall be installed in sleeping units.
EXCEPTION:
Carbon monoxide detection shall be allowed to be installed outside of each separate sleeping area in the immediate vicinity of the sleeping unit where the sleeping unit or its attached bathroom does not contain a fuel-burning appliance or fuel-burning fireplace and is not served by a forced air furnace.
915.2.3 Group E occupancies. When required by Section 915.1 in new buildings, or by Chapter 11 of the International Fire Code, carbon monoxide detection shall be installed in classrooms in Group E occupancies. Carbon monoxide alarm signals shall be automatically transmitted to an on-site location that is staffed by school personnel.
EXCEPTIONS:
1. Carbon monoxide alarm signals shall not be required to be automatically transmitted to an on-site location that is staffed by school personnel in Group E occupancies with an occupant load of 50 or less.
 
2. Carbon monoxide alarm signals shall not be required to be automatically transmitted to an on-site location that is staffed by school personnel in Group E occupancies where an exception contained in Section 915.1 applies, or in Group E occupancies where signals are transmitted to an off-site service monitored by a third party, such as a service that monitors fire protection systems in the building.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 16-03-064, § 51-50-0915, filed 1/19/16, effective 7/1/16.]



PDF51-50-1004

Section 1004Occupant load.

Table 1004.5, Maximum Floor Area Allowances Per Occupant
Table 1004.5
Maximum Floor Area Allowance Per Occupant
FUNCTION OF SPACE
OCCUPANT LOAD FACTORa
Accessory storage areas, mechanical equipment room
300 gross
Agricultural building
300 gross
Aircraft hangars
500 gross
Airport terminal
 
 
Baggage claim
20 gross
 
Baggage handling
300 gross
 
Concourse
100 gross
 
Waiting areas
15 gross
Assembly
 
 
Gaming floors (keno, slots, etc.)
11 gross
 
Exhibit gallery and museum
30 net
 
Billiard table/game table area
50 gross
Assembly with fixed seats
See Section 1004.6
Assembly without fixed seats
 
 
Concentrated (chairs only - not fixed)
7 net
 
Standing space
5 net
 
Unconcentrated (tables and chairs)
15 net
Bowling centers, allow 5 persons for each lane including 15 feet of runway, and for additional areas
7 net
Business areas
 
 
Concentrated business use areas
150 gross (See Section 1004.8)
Courtrooms - Other than fixed seating areas
40 net
Day care
35 net
Dormitories
50 gross
Educational
 
 
Classroom area
20 net
 
Shops and other vocational room areas
50 net
Exercise rooms
50 gross
Group H-5 fabrication and manufacturing areas
200 gross
Industrial areas
100 gross
Institutional areas
 
 
Inpatient treatment areas
240 gross
 
Outpatient areas
100 gross
 
Sleeping areas
120 gross
Kitchens, commercial
200 gross
Library
 
 
Reading rooms
50 net
 
Stack area
100 gross
Locker rooms
50 gross
Mall buildings - Covered and open
See Section 402.8.2
Mercantile
60 gross
 
Storage, stock, shipping areas
300 gross
 
Group M art gallery
30 gross
Parking garages
200 gross
Residential
200 gross
Skating rinks, swimming pools
 
 
Rink and pool
50 gross
 
Decks
15 gross
Stages and platforms
15 net
Warehouses
500 gross
For SI: 1 foot = 304.8 mm, 1 square foot = 0.0929 m2.
a
Floor area in square feet per occupant.
[Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 20-01-090, § 51-50-1004, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-1004, filed 12/26/18, effective 7/1/19; WSR 16-03-064, § 51-50-1004, filed 1/19/16, effective 7/1/16.]



PDF51-50-1005

Section 1005—Reserved.

[Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-067, § 51-50-1005, filed 2/1/13, effective 7/1/13. Statutory Authority: Chapter 19.27 RCW. WSR 10-24-059, § 51-50-1005, filed 11/29/10, effective 7/1/11.]



PDF51-50-1006

Section 1006Number of exits and exit access doorways.

Table 1006.2.1
Spaces with One Exit or Exit Access Doorway
OCCUPANCY
MAXIMUM OCCUPANT
LOAD OF SPACE
MAXIMUM COMMON PATH OF EGRESS TRAVEL DISTANCE (feet)
Without Sprinkler System (feet)
With Sprinkler System (feet)
Occupant Load
OL ≤ 30
OL ≥ 30
Ac, Eh, M
49
75
75
75a
B
49
100
75
100a
F
49
75
75
100a
H-1, H-2, H-3
3
NP
NP
25b
H-4, H-5
10
NP
NP
75b
I-1, I-2d, I-4
10
NP
NP
75b
I-3
10
NP
NP
100a
R-1
10
NP
NP
75a
R-2
20
NP
NP
125a
R-3e
20
NP
NP
125a,g
R-4e
20
NP
NP
125a,g
Sf
29
100
75
100a
U
49
100
75
75a
For SI: 1 foot = 304.8 mm.
NP = Not Permitted.
 
a
Buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2. See Section 903 for occupancies where automatic sprinkler systems are permitted in accordance with Section 903.3.1.2.
 
b
Group H occupancies equipped throughout with an automatic sprinkler system in accordance with Section 903.2.5.
 
c
For a room or space used for assembly purposes having fixed seating, see Section 1029.8.
 
d
For the travel distance limitations in Group I-2, see Section 407.4.
 
e
The common path of egress travel distance shall only apply in a Group R-3 occupancy located in a mixed occupancy building.
 
f
The length of common path of egress travel distance in a Group S-2 open parking garage shall be not more than 100 feet.
 
g
For the travel distance limitations in Groups R-3 and R-4 equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.3, see Section 1006.2.2.6.
 
h
Day care facilities, rooms or spaces where care is provided for more than 10 children that are 2 1/2 years of age or less, shall have access to not less than two exits or exit access doorways.
1006.2.1 Egress based on occupant load and common path of egress travel distance. Two exits or exit access doorways from any space shall be provided where the design occupant load or the common path of egress travel distance exceeds the values listed in Table 1006.2.1. The cumulative occupant load from adjacent rooms, areas or spaces shall be determined in accordance with Section 1004.2.
EXCEPTIONS:
1. The number of exits from foyers, lobbies, vestibules or similar spaces need not be based on cumulative occupant loads for areas discharging through such spaces, but the capacity of the exits from such spaces shall be based on applicable cumulative occupant loads.
 
2. Care suites in Group I-2 occupancies complying with Section 407.4.
 
3. Unoccupied mechanical rooms and penthouses are not required to comply with the common path of egress travel distance measurement.
1006.2.2.4 Group I-4 means of egress. This section is not adopted.
1006.2.2.7 Electrical equipment rooms. Rooms containing electrical equipment shall be provided with a second exit or exit access doorways as required by NFPA 70 Article 110 where all of the following apply:
1. The electrical equipment is rated at 1,200 amperes or more.
2. The electrical equipment is over 6 feet (1829 mm) wide.
3. The electrical equipment contains overcurrent devices, switching devices or control devices.
1006.3.3 Single exits. A single exit or access to a single exit shall be permitted from any story or occupied roof where one of the following conditions exists:
1. The occupant load, number of dwelling units and exit access travel distance within the portion of the building served by the single exit do not exceed the values in Table 1006.3.3(1) or 1006.3.3(2).
2. Rooms, areas and spaces complying with Section 1006.2.1 with exits that discharge directly to the exterior at the level of exit discharge, are permitted to have one exit or access to a single exit.
3. Parking garages where vehicles are mechanically parked shall be permitted to have one exit or access to a single exit.
4. Groups R-3 and R-4 occupancies shall be permitted to have one exit or access to a single exit.
5. Individual single-story or multistory dwelling units shall be permitted to have a single exit or access to a single exit from the dwelling unit provided that both of the following criteria are met:
5.1. The dwelling unit complies with Section 1006.2.1 as a space with one means of egress.
5.2. Either the exit from the dwelling unit discharges directly to the exterior at the level of exit discharge, or the exit access outside the dwelling unit's entrance door provides access to not less than two approved independent exits.
Table 1006.3.3(1)
Stories with One Exit or Access to One Exit for R-2 Occupancies
Story
Occupancy
Maximum Number of Dwelling Units
Maximum Exit Access Travel Distance
Basement, first, second, or third story above grade plane
R-2a,b
4 dwelling units
125 feet
Fourth story above grade plane and higher
NP
NA
NA
For SI: 1 foot = 304.8 mm.
NP = Not Permitted.
NA = Not Applicable.
 
a
Buildings classified as Group R-2 equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2 and provided with emergency escape and rescue openings in accordance with Section 1030.
 
b
This table is used for R-2 occupancies consisting of dwelling units. For R-2 occupancies consisting of sleeping units, use Table 1006.3.3(2).
Table 1006.3.3(2)
Stories with One Exit or Access to One Exit for Other Occupancies
Story
Occupancy
Maximum Occupant Load per Story
Maximum Exit Access Travel Distance (feet)
First story above or below grade plane
A, Bb, E, Fb, M, U
49
75
H-2, H-3
3
25
H-4, H-5, I, R-1, R-2a,c
10
75
Sb,d
29
75
Second story above grade plane
B, F, M, Sd
29
75
Third story above grade plane and higher
NP
NA