PDFWAC 51-50-0504
Section 504—Building 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; 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 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 | ||
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 | 4 | 4 | 4 | 10 | 7 | 5 | 5 | 4 | 2 | |
S-2 | NS | UL | 11 | 5 | 3 | 4 | 3 | 4 | 4 | 4 | 5 | 4 | 2 |
S | UL | 12 | 6 | 4 | 5 | 4 | 12 | 8 | 5 | 6 | 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; 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 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 | ||
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 2702.17 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 23-23-102, § 51-50-0504, filed 11/15/23, effective 3/16/24; WSR 22-13-094, 23-12-103, and 23-20-023, § 51-50-0504, filed 6/14/22, 6/7/23, and 9/25/23, effective 3/15/24; 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.]