Washington Administrative Code › Title 51 - Enterprise Services, Department of (Building Code Council) › Chapter 51-50 - State Building Code adoption and amendment of the 2021 edition of the International Building Code › Section 51-50-0504 - Section 504-Building height and number of stories

Current through Register Vol. 24-14, July 15, 2024
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 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
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 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 2702.17 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
				  chapters
				  19.27 and
				  34.05 RCW. 13-04-067, §
				  51-50-0504, filed 2/1/13, effective 7/1/13. Statutory Authority:
				  Chapter
				  19.27 RCW. 10-24-059,
				  § 51-50-0504, filed 11/29/10, effective
				  7/1/11.