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51-51-0301  <<  51-51-0302 >>   51-51-0303

WAC 51-51-0302

Agency filings affecting this section

Section R302—Fire-resistant construction.

R302.1 Exterior walls. Construction, projections, openings and penetrations of exterior walls of dwellings and accessory buildings shall comply with Table R302.1(1); or dwellings equipped throughout with an automatic sprinkler system installed in accordance with Section P2904 shall comply with Table R302.1(2).
EXCEPTIONS:
1. Walls, projections, openings or penetrations in walls perpendicular to the line used to determine the fire separation distance.
 
2. Walls of dwellings and accessory structures located on the same lot.
 
3. Detached tool sheds and storage sheds, playhouses and similar structures exempted from permits are not required to provide protection based on location on the lot. Projections beyond the exterior wall shall not extend over the lot line.
 
4. Detached garages accessory to a dwelling located within 2 feet (610 mm) of a lot line are permitted to have roof eave projections not exceeding 4 inches (102 mm).
 
5. Foundation vents installed in compliance with this code are permitted.
TABLE R302.1(1)
EXTERIOR WALLS
Exterior Wall Element
Minimum Fire-Resistance Rating
Minimum Fire Separation Distance
Walls
Fire-resistance rated
1-hour tested in accordance with ASTM E 119 or UL 263 with exposure from both sides
< 5 feet
 
Not fire-resistance rated
0 hours
≥ 5 feet
Projections
Fire-resistance rated
1 hour on the undersidea, b
≥ 2 feet to < 5 feet
 
Not fire-resistance rated
0 hours
≥ 5 feet
Openings in walls
Not allowed
N/A
< 3 feet
 
25% maximum of wall area per story
0 hours
3 feet
 
Unlimited
0 hours
5 feet
Penetrations
All
Comply with Section R302.4
< 5 feet
 
 
None required
5 feet
For IS: 1 foot = 304.8 mm. N/A = Not Applicable
a Roof eave fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave if fire blocking is provided from the wall top plate to the underside of the roof sheathing.
b Roof eave fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave provided no gable vent openings are installed.
Table R302.1(2)
Exterior Walls—Dwellings with Fire Sprinklers
Exterior Wall Element
Minimum Fire-Resistance Rating
Minimum Fire Separation Distance
Walls
Fire-resistance rated
1-hour tested in accordance with ASTM E 119 or UL 263 with exposure from the outside
0 feet
 
Not fire-resistance rated
0 hours
3 feeta
Projections
Fire-resistance rated
1 hour on the undersideb, c
2 feeta
 
Not fire-resistance rated
0 hours
3 feet
Openings in walls
Not allowed
N/A
< 3 feet
 
Unlimited
0 hours
3 feeta
Penetrations
All
Comply with Section R302.4
< 3 feet
 
 
None required
3 feeta
For IS: 1 foot = 304.8 mm. N/A = Not Applicable
a For residential subdivisions where all dwellings are equipped throughout with an automatic sprinkler system installed in accordance with P2904, the fire separation distance for nonrated exterior walls and rated projections shall be permitted to be reduced to 0 feet, and unlimited unprotected openings and penetrations shall be permitted, where the adjoining lot provides an open setback yard that is 6 feet or more in width on the opposite side of the property line.
b Roof eave fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave if fire blocking is provided from the wall top plate to the underside of the roof sheathing.
c Roof eave fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave provided no gable vent openings are installed.
R302.2.1 Continuity. The fire-resistance-rated wall or assembly separating townhouses shall be continuous from the foundation to the underside of the roof sheathing, deck or slab. The fire-resistance rating shall extend the full length of the wall or assembly, including wall extensions through and separating attached enclosed accessory structures.
Where a story extends beyond the exterior wall of a story below:
1. The fire-resistance-rated wall or assembly shall extend to the outside edge of the upper story; or
2. The underside of the exposed floor-ceiling assembly shall be protected as required for projections in Section R302.
R302.2.4 Structural independence. Each individual townhouse shall be structurally independent.
EXCEPTIONS:
1. Foundation supporting exterior walls or common walls.
 
2. Structural roof and wall sheathing from each unit may be fastened to the common wall framing.
 
3. Nonstructural wall and roof coverings.
 
4. Flashing at termination of roof covering over common wall.
 
5. Townhouses separated by a common 1-hour fire-resistance-rated wall as provided in Section R302.2.
 
6. Floor sheathing may fasten to the floor framing of both units.
R302.3.1 Supporting construction. When floor assemblies are required to be fire-resistance rated by Section R302.3, the supporting construction of such assemblies shall have an equal or greater fire-resistance rating.
EXCEPTION:
The supporting construction is not required to be fire-resistance rated where:
 
1. Automatic fire sprinklers are installed in accordance with appendix R in both dwelling units;
 
or
 
2. All required smoke alarms in both dwelling units are interconnected in such a manner that the actuation of one alarm will activate all alarms in both dwelling units.
[Statutory Authority: Chapters 19.27A and 34.05 RCW. WSR 13-23-084, § 51-51-0302, filed 11/19/13, effective 4/1/14. Statutory Authority: RCW 19.27.031 and chapters 19.27 and 34.05 RCW. WSR 13-04-068, § 51-51-0302, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW 19.27.031 and 19.27.074. WSR 10-03-098, § 51-51-0302, 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 09-04-023, § 51-51-0302, filed 1/27/09, effective 7/1/09; WSR 08-01-102, § 51-51-0302, filed 12/18/07, effective 4/1/08.]