WSR 20-21-021
PERMANENT RULES
BUILDING CODE COUNCIL
[Filed October 9, 2020, 1:57 p.m., effective November 9, 2020]
Effective Date of Rule: Thirty-one days after filing.
Purpose: The purpose of the permanent rule making is to adopt changes noted in CR-105 Expedited rule making (WSR 20-15-083).
Citation of Rules Affected by this Order: Amending 8.
Statutory Authority for Adoption: RCW 19.27.031.
Other Authority: RCW 19.27.074.
Adopted under notice filed as WSR 20-15-083 on July 15, 2020.
Number of Sections Adopted in Order to Comply with Federal Statute: New 0, Amended 0, Repealed 0; Federal Rules or Standards: New 0, Amended 0, Repealed 0; or Recently Enacted State Statutes: New 0, Amended 0, Repealed 0.
Number of Sections Adopted at the Request of a Nongovernmental Entity: New 0, Amended 0, Repealed 0.
Number of Sections Adopted on the Agency's own Initiative: New 0, Amended 0, Repealed 0.
Number of Sections Adopted in Order to Clarify, Streamline, or Reform Agency Procedures: New 0, Amended 8, Repealed 0.
Number of Sections Adopted using Negotiated Rule Making: New 0, Amended 0, Repealed 0; Pilot Rule Making: New 0, Amended 0, Repealed 0; or Other Alternative Rule Making: New 0, Amended 0, Repealed 0.
Date Adopted: September 21, 2020.
Diane Glenn
Chair
NEW SECTION
WAC 51-50-0110Section 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.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-0308Section 308—Institutional 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 ((308.3.1 or 308.3.2))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.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-0504Section 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
270
180
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 ((2017))2020 NEC Section 701.12, options (((A), (B),)) (C), (D), (E), (F), (H) or (((G)))(J) or subsequent revised section number(s).
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-0510Section 510—Special 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).
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-0602Section 602—Construction 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.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-0603Section 603—Combustible 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.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-0705Section 705—Exterior 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.
((705.2.5))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.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-0903Section 903—Automatic 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 ((5-1))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.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-0909Section 909—Smoke control systems.
((909.6.3 Pressurized stairways and elevator hoistways. Where stairways or elevator hoistways are pressurized, such pressurization systems shall comply with the requirements of Section 909.20 of this code for stair pressurization and 909.21 of the International Building Code and Fire Code as necessary to determine that the stairway or elevator hoistways meets the pressurization requirements of the code. Stairway and elevator hoistway pressurization systems in high-rise buildings, underground buildings, and in airport traffic control towers shall comply with International Building Code and International Fire Code Sections 909 as smoke control systems.
Stairway pressurization systems in other than high-rise buildings, underground buildings, or airport traffic control towers are smoke control systems but shall only be required to comply with the following International Building Code 909 Sections: 909.1, 909.2, 909.3, 909.6 with the exception of Sections 909.6.1, 909.10 with the exception of Sections 909.10.2, 909.11 with the exception of Sections 909.11.1, 909.12 with the exception of Sections 909.12.3.2, 909.13, 909.14, 909.17, 909.18 with the exception of Sections 909.18.2 and 909.18.9, 909.19, 909.20.5 and 909.20.6. Design drawings shall include a description of system operation, the conditions for system testing and the criteria for system acceptance to achieve the code minimum performance of the smoke control system. Stairway pressurization systems shall be maintained in accordance with Section 909.20 of the International Fire Code.
Elevator hoistway pressurization systems in other than high-rise buildings, underground buildings, or airport traffic control towers are smoke control systems but shall only be required to comply with the following International Building Code 909 Sections: 909.1, 909.2, 909.3, 909.6 with the exception of Sections 909.6.1, 909.10 with the exception of Sections 909.10.2, 909.11 with the exception of Sections 909.11.1, 909.12 with the exception of Sections 909.12.3.2, 909.13, 909.14, 909.17, 909.18 with the exception of Sections 909.18.2 and 909.18.9, 909.19, and 909.21 with the exception of Sections 909.21.2, 909.21.9, and 909.21.10. Design drawings shall include a description of system operation, the conditions for system testing and the criteria for system acceptance to achieve the code minimum performance of the smoke control system. Elevator hoistway pressurization systems shall be maintained in accordance with Section 909.20 of the International Fire Code.))
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.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-1006Section 1006—Number 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.
((1006.2.2.6))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
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
Group B, F and S occupancies in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 shall have a maximum exit access travel distance of 100 feet.
 
c
This table is used for R-2 occupancies consisting of sleeping units. For R-2 occupancies consisting of dwelling units, use Table 1006.3.3(1).
 
d
The length of exit access travel distance in a Group S-2 open parking garage shall be not more than 100 feet.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-1009Section 1009—Accessible means of egress.
1009.1 Accessible means of egress required. Accessible means of egress shall comply with this section. Accessible spaces shall be provided with not less than one accessible means of egress. Where more than one means of egress is required by Section 1006.2 or 1006.3 from any accessible space, each accessible portion of the space shall be served by not less than two accessible means of egress.
EXCEPTIONS:
1. Accessible means of egress are not required to be provided in existing buildings.
 
2. One accessible means of egress is required from an accessible mezzanine level in accordance with Section 1009.3, 1009.4 or 1009.5.
 
3. In assembly areas with ramped aisles or stepped aisles, one accessible means of egress is permitted where the common path of egress travel is accessible and meets the requirements in Section 1029.8.
 
4. In parking garages, accessible means of egress are not required to serve parking areas that do not contain accessible parking spaces.
1009.2.1 Elevators required. In buildings where a required accessible floor or accessible occupied roof is four or more stories above or below a level of exit discharge, not less than one required accessible means of egress shall be an elevator complying with Section 1009.4.
EXCEPTIONS:
1. In buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2, the elevator shall not be required on floors provided with a horizontal exit and located at or above the levels of exit discharge.
 
2. In buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2, the elevator shall not be required on floors provided with a ramp conforming to the provisions of Section 1012.
1009.8 Two-way communication. A two-way communication system complying with Sections 1009.8.1 and 1009.8.2 shall be provided at the landing serving each elevator or bank of elevators on each accessible floor that is one or more stories above or below the level of exit discharge.
EXCEPTIONS:
1. Two-way communication systems are not required at the landing serving each elevator or bank of elevators where the two-way communication system is provided within areas of refuge in accordance with Section 1009.6.5.
 
2. Two-way communication systems are not required on floors provided with ramps that provide a direct path of egress travel to grade or the level of exit discharge conforming to the provisions of Section 1012.
 
3. Two-way communication systems are not required at the landings serving only service elevators that are not designated as part of the accessible means of egress or serve as part of the required accessible route into a facility.
 
4. Two-way communication systems are not required at the landings serving only freight elevators.
 
5. Two-way communication systems are not required at the landing serving a private residence elevator.
 
6. Two-way communication systems are not required in Group I-2 or I-3 facilities.
1009.8.1 System requirements. Two-way communication systems shall provide communication between each required location and the fire command center or a central control point location approved by the fire department. Where the central control point is not a constantly attended location, a two-way communication system shall have a timed automatic telephone dial-out capability to a monitoring location. The two-way communication system shall include both audible and visible signals. The two-way communication system shall have a battery backup or an approved alternate source of power that is capable of 90 minutes use upon failure of the normal power source.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-1019Section 1019—Exit access stairways and ramps.
1019.3 Occupancies other than Groups I-2 and I-3. In other than Groups I-2 and I-3 occupancies, floor openings containing exit access stairways or ramps shall be enclosed with a shaft enclosure constructed in accordance with Section 713.
EXCEPTIONS:
1. Exit access stairways and ramps that serve or atmospherically communicate between only two stories. Such interconnected stories shall not be open to other stories.
 
2. In Group R-1, R-2 or R-3 occupancies, exit access stairways and ramps connecting four stories or less serving and contained within an individual dwelling unit or sleeping unit or live/work unit.
 
3. Exit access stairways serving and contained within a Group R-3 congregate residence ((or a Group R-4 facility)) are not required to be enclosed.
 
4. Exit access stairways and ramps in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1, where the area of the vertical opening between stories does not exceed twice the horizontal projected area of the stairway or ramp and the opening is protected by a draft curtain and closely spaced sprinklers in accordance with NFPA 13. In other than Group B and M occupancies, this provision is limited to openings that do not connect more than four stories.
 
5. Exit access stairways and ramps within an atrium complying with the provisions of Section 404.
 
6. Exit access stairways and ramps in open parking garages that serve only the parking garage.
 
7. Exit access stairways and ramps serving smoke-protected or open-air assembly seating complying with the exit access travel distance requirements of Section 1029.7.
 
8. Exit access stairways and ramps between the balcony, gallery or press box and the main assembly floor in occupancies such as theaters, places of religious worship, auditoriums, and sports facilities.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-10240Section 1024—Exit passageways.
((1024.8))1024.9 Exit passageway exterior walls. Exterior walls of the exit passageway shall comply with Section 705. Where nonrated walls or unprotected openings enclose the exterior of the exit passageway and the walls or openings are exposed by other parts of the building at an angle of less than 180 degrees (3.14 rad), the building exterior walls within 10 feet (3048 mm) horizontally of a nonrated wall or unprotected opening shall have a fire-resistance rating of not less than 1 hour. Openings within such exterior walls shall be protected by opening protectives having a fire-protection rating of not less than 3/4 hour. This construction shall extend vertically from the ground to a point 10 feet (3048 mm) above the floor of the exit passageway, or to the roof line, whichever is lower.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-1107Section 1107—Dwelling units and sleeping units.
1107.5.1.1 Accessible units in Group I-1, Condition 1. In Group I-1, Condition 1, at least 4 percent, but not less than one, of the dwelling units and sleeping units shall be accessible units.
EXCEPTIONS:
1. In not more than 50 percent of the accessible units, water closets shall not be required to comply with ICC A117.1 where such water closets comply with Section 1109.2.4.
 
2. In not more than 50 percent of the accessible units, roll-in-type showers shall not be required to comply with ICC A117.1 where roll-in-type showers comply with Section 1109.2.5.
1107.5.1.2 Accessible units in Group I-1, Condition 2. In Group I-1, Condition 2, at least 10 percent, but not less than one, of the dwelling units and sleeping units shall be accessible units.
EXCEPTIONS:
1. In not more than 90 percent of the accessible units, water closets shall not be required to comply with ICC A117.1 where such water closets comply with Section 1109.2.4.
 
2. In not more than 90 percent of the accessible units, roll-in-type showers shall not be required to comply with ICC A117.1 where roll-in-type showers comply with Section 1109.2.5.
1107.5.4 Group I-2 rehabilitation facilities. In hospitals and rehabilitation facilities of Group I-2 occupancies that specialize in treating conditions that affect mobility, or units within either that specialize in treating conditions that affect mobility, 100 percent of the dwelling units and sleeping units shall be accessible units.
EXCEPTIONS:
1. In not more than 50 percent of the accessible units, water closets shall not be required to comply with ICC A117.1 where such water closets comply with Section 1109.2.4.
 
2. In not more than 50 percent of the accessible units, roll-in-type showers shall not be required to comply with ICC A117.1 where roll-in-type showers comply with Section 1109.2.5.
1107.6.2.2.1 Type A units. In Group R-2 Occupancies containing more than 10 dwelling units or sleeping units, at least 5 percent, but not less than one, of the units shall be a Type A unit. All units on a site shall be considered to determine the total number of units and the required number of Type A units. Type A units shall be dispersed among the various classes of units, as described in Section 1107.6. Bedrooms in monasteries and convents shall be counted as sleeping units for the purpose of determining the number of units. Where the sleeping units are grouped into suites, only one sleeping unit in each suite shall count towards the number of required Type A units.
EXCEPTIONS:
1. The number of Type A units is permitted to be reduced in accordance with Section 1107.7.
 
2. Existing structures on a site shall not contribute to the total number of units on a site.
1107.5.1 Group I-1. Accessible units and Type B units shall be provided in Group I-1 occupancies in accordance with Sections 1107.5.1.1 through 1107.5.1.3.
1107.5.1.1 Accessible units in Group I-1, Condition 1. In Group I-1, Condition 1, at least 4 percent, but not less than one, of the dwelling units and sleeping units shall be accessible units.
EXCEPTIONS:
1. In not more than 50 percent of the accessible units, water closets shall not be required to comply with ICC A117.1 where such water closets comply with Section 1109.2.2.
 
2. In not more than 50 percent of the accessible units, roll-in-type showers shall not be required to comply with ICC A117.1 where roll-in-type showers comply with Section 1109.2.3.
1107.5.1.2 Accessible units in Group I-1, Condition 2. In Group I-1, Condition 2, at least 10 percent, but not less than one, of the dwelling units and sleeping units shall be accessible units.
EXCEPTIONS:
1. In not more than 50 percent of the accessible units, water closets shall not be required to comply with ICC A117.1 where such water closets comply with Section 1109.2.2.
 
2. In not more than 50 percent of the accessible units, roll-in-type showers shall not be required to comply with ICC A117.1 where roll-in-type showers comply with Section 1109.2.3.
1107.5.1.3 Type B units. In structures with four or more dwelling units or sleeping units intended to be occupied as a residence, every dwelling unit and sleeping unit intended to be occupied as a residence shall be a Type B unit.
EXCEPTION:
The number of Type B units is permitted to be reduced in accordance with Section 1107.7.
1107.5.2 Group I-2 nursing homes. Accessible units and Type B units shall be provided in nursing homes of Group I-2, Condition 1 occupancies in accordance with Sections 1107.5.2.1 and 1107.5.2.2.
1107.5.2.1 Accessible units. At least 50 percent but not less than one of each type of the dwelling units and sleeping units shall be accessible units.
EXCEPTIONS:
1. In not more than 90 percent of the accessible units, water closets shall not be required to comply with ICC A117.1 where such water closets comply with Section 1109.2.2.
 
2. In not more than 90 percent of the accessible units, roll-in-type showers shall not be required to comply with ICC A117.1 where roll-in-type showers comply with Section 1109.2.3.
((1107.5.2.2 Type B units. In structures with four or more dwelling units or sleeping units intended to be occupied as a residence, every dwelling unit and sleeping unit intended to be occupied as a residence shall be a Type B unit.
EXCEPTION:
The number of Type B units is permitted to be reduced in accordance with Section 1107.7.))
1107.5.4 Group I-2 rehabilitation facilities. In hospitals and rehabilitation facilities of Group I-2 occupancies that specialize in treating conditions that affect mobility, or units within either that specialize in treating conditions that affect mobility, 100 percent of the dwelling units and sleeping units shall be accessible units.
EXCEPTIONS:
1. In not more than 50 percent of the accessible units, water closets shall not be required to comply with ICC A117.1 where such water closets comply with Section 1109.2.2.
 
2. In not more than 50 percent of the accessible units, roll-in-type showers shall not be required to comply with ICC A117.1 where roll-in-type showers comply with Section 1109.2.3.
1107.6.2.3 Group R-2 other than live/work units, apartment houses, monasteries and convents. In Group R-2 Occupancies, other than live/work units, apartment houses, monasteries and convents falling within the scope of Sections 1107.6.2.1 and 1107.6.2.2, accessible units and Type B units shall be provided in accordance with Sections 1107.6.2.3.1 and 1107.6.2.3.2. Bedrooms within congregate living facilities shall be counted as sleeping units for the purpose of determining the number of units. Where the sleeping units are grouped into suites, only one sleeping unit in each suite shall be permitted to count towards the number of required accessible units. Accessible units shall be dispersed among the various classes of units, as described in Section 1107.6.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-11090Section 1109—Other features and facilities.
1109.2 Toilet and bathing facilities. Each toilet room and bathing room shall be accessible. Where a floor level is not required to be connected by an accessible route, the only toilet rooms or bathing rooms provided within the facility shall not be located on the inaccessible floor. Except as provided for in Sections 1109.2 and 1109.2.3((, 1109.2.4 and 1109.2.5)) at least one of each type of fixture, element, control or dispenser in each accessible toilet room and bathing room shall be accessible.
EXCEPTIONS:
1. Toilet rooms or bathing rooms accessed only through a private office, not for common or public use and intended for use by a single occupant, shall be permitted to comply with the specific exceptions in ICC A117.1.
 
2. This section is not applicable to toilet and bathing rooms that serve dwelling units or sleeping units that are not required to be accessible by Section 1107.
 
3. Where multiple single-user toilet rooms or bathing rooms are clustered at a single location, at least 50 percent but not less than one room for each use at each cluster shall be accessible. Where these rooms are designated as gender-neutral, the total number of accessible toilet or bathing rooms shall not be less than the sum of required accessible separate male plus female rooms.
 
4. Where no more than one urinal is provided in a toilet room or bathing room, the urinal is not required to be accessible.
 
5. Toilet rooms or bathing rooms that are part of critical care or intensive care patient sleeping rooms serving accessible units are not required to be accessible.
 
6. Toilet rooms or bathing rooms designed for bariatrics patients are not required to comply with the toilet room and bathing room requirement in ICC A117.1. The sleeping units served by bariatrics toilet or bathing rooms shall not count toward the required number of accessible sleeping units.
 
7. Where permitted in Section 1107, in toilet rooms or bathrooms serving accessible units, water closets designed for assisted toileting shall be permitted to comply with Section ((1109.2.2))1109.2.4.
 
8. Where permitted in Section 1107, in bathrooms serving accessible units, showers designed for assisted toileting shall be permitted to comply with Section ((1109.2.3))1109.2.5.
 
9. Where toilet facilities are primarily for children's use, required accessible water closets, toilet compartments and lavatories shall be permitted to comply with children's provision of ICC A117.1.
((1109.2.2))1109.2.4 Water closets designed for assisted toileting. Water closets designed for assisted toileting shall comply with Sections ((1109.2.2.1))1109.2.4.1 through ((1109.2.2.6))1109.2.4.6.
((1109.2.2.1))1109.2.4.1 Location. The centerline of the water closet shall be 24 inches (610 mm) minimum and 26 inches (660 mm) maximum from one side of the required clearance.
((1109.2.2.2))1109.2.4.2 Clearance. Clearance around the water closet shall comply with Sections ((1109.2.2.2.1))1109.2.4.2.1 through ((1109.2.2.2.3))1109.2.4.2.3.
((1109.2.2.2.1))1109.2.4.2.1 Clearance width. Clearance around a water closet shall be 66 inches (1675 mm) minimum in width, measured perpendicular from the side of the clearance that is 24 inches (610 mm) minimum and 26 inches (660 mm) maximum from the water closet centerline.
((1109.2.2.2.2))1109.2.4.2.2 Clearance depth. Clearance around the water closet shall be 78 inches (1980 mm) minimum in depth, measured perpendicular from the rear wall.
((1109.2.2.2.3))1109.2.4.2.3 Clearance overlap. The required clearance around the water closet shall be permitted overlaps in accordance with ICC A117.1 Section 604.3.3.
((1109.2.2.3))1109.2.4.3 Height. The height of the water closet seats shall comply with ICC A117.1 Section 604.4.
((1109.2.2.4))1109.2.4.4 Swing–up grab bars. The swing-up grab bars shall comply with ICC A117.1 Sections 609.2 and 609.8. Swing–up grab bars shall be provided on both sides of the water closet and shall comply with all of the following:
1. The centerline of the grab bar shall be 14 inches minimum to 16 inches (356 mm to 405 mm) maximum from the centerline of the water closet.
2. The length of the grab bar is 36 inches (915 mm) minimum in length, measured from the rear wall to the end of the grab bar.
3. The top of the grab bar in the down position is 30 inches (760 mm) minimum and 34 inches (865 mm) maximum above the floor.
((1109.2.2.5))1109.2.4.5 Flush controls. Flush controls shall comply with ICC A117.1 Section 604.6.
((1109.2.2.6))1109.2.4.6 Dispensers. Toilet paper dispensers shall be mounted on at least one of the swing-up grab bars and the outlet of the dispenser shall be located at 24 inches (610 mm) minimum to 36 inches (915 mm) maximum from the rear wall.
((1109.2.3))1109.2.5 Standard roll-in-type shower compartment designed for assisted bathing. Standard roll-in-type shower compartments designed for assisted bathing shall comply with Sections ((1109.2.3.1))1109.2.5.1 through ((1109.2.3.8))1109.2.5.8.
((1109.2.3.1))1109.2.5.1 Size. Standard roll-in-type shower compartments shall have a clear inside dimension of 60 inches (1525 mm) minimum in width and 30 inches (760 mm) minimum in depth, measured at the center point of opposing sides. An entry 60 inches (1525 mm) minimum in width shall be provided.
((1109.2.3.2))1109.2.5.2 Clearance. A clearance of 60 inches (1525 mm) minimum in length adjacent to the 60 inch (1525 mm) width of the open face of the shower compartment, and 30 inches (760 mm) minimum in depth, shall be provided.
EXCEPTIONS:
1. A lavatory complying with Section 606 shall be permitted at one end of the clearance.
 
2. Where the shower compartment exceeds minimum sizes, the clear floor space shall be placed adjacent to the grab bars and 30 inches minimum from the back wall.
((1109.2.3.3))1109.2.5.3 Grab bars. Grab bars shall comply with ICC A117.1 Section 609 and shall be provided in accordance with Sections ((1109.2.3.3.1))1109.2.5.3.1 and ((1109.2.3.3.2))1109.2.5.3.2. In standard roll-in-type shower compartments, grab bars shall be provided on three walls. Where multiple grab bars are used, required horizontal grab bars shall be installed at the same height above the floor. Grab bars can be separate bars or one continuous bar.
((1109.2.3.3.1))1109.2.5.3.1 Back-wall grab bar. The back-wall grab bar shall extend the length of the back wall and extend within 6 inches (150 mm) maximum from the two adjacent side walls.
EXCEPTION:
The back wall grab bar shall not be required to exceed 48 inches (1220 mm) in length. The rear grab bar shall be located with one end within 6 inches maximum of a side wall with a grab bar complying with Section ((1109.2.3.3.2))1109.2.5.3.2.
((1109.2.3.3.2))1109.2.5.3.2 Side-wall grab bars. The side-wall grab bars shall extend the length of the wall and extend within 6 inches (150 mm) maximum from the adjacent back wall.
EXCEPTIONS:
1. The side-wall grab bar shall not be required to exceed 30 inches (760 mm) in length. The side grab bar shall be located with one end within 6 inches maximum of the back wall with a grab bar complying with Section ((1109.2.3.3.1))1109.2.5.3.1.
 
2. Where the side walls are located 72 inches (1830 mm) or greater apart, a grab bar is not required on one of the side walls.
((1109.2.3.4))1109.2.5.4 Seats. Wall-mounted folding seats shall not be installed.
((1109.2.3.5))1109.2.5.5 Controls and hand showers. In standard roll-in-type showers, the controls and hand shower shall be located 38 inches (965 mm) minimum and 48 inches (1220 mm) maximum above the shower floor. Controls shall be located to facilitate caregiver access.
((1109.2.3.6))1109.2.5.6 Hand showers. Hand showers shall comply with ICC A117.1 Section 608.5.
((1109.2.3.7))1109.2.5.7 Thresholds. Thresholds shall comply with ICC A117.1 Section 608.6.
((1109.2.3.8))1109.2.5.8 Shower enclosures. Shower compartment enclosures for shower compartments shall comply with ICC A117.1 Section 608.7.
((1109.2.3.9))1109.2.5.9 Water temperature. Water temperature shall comply with ICC A117.1 Section 608.8.
1109.5.1 Minimum number. Not fewer than two drinking fountains shall be provided. One drinking fountain shall comply with the requirements for people who use a wheelchair and one drinking fountain shall comply with the requirements for standing persons.
EXCEPTIONS:
1. A single drinking fountain with two separate spouts that complies with the requirements for people who use a wheelchair and standing persons shall be permitted to be substituted for two separate drinking fountains.
 
2. Where drinking fountains are primarily for children's use, drinking fountains for people using wheelchairs shall be permitted to comply with the children's provisions in ICC A117.1 and drinking fountains for standing children shall be permitted to provide the spout at 30 inches (762 mm) minimum above the floor.
 
3. In all occupancies that require more than two drinking fountains per floor or secured area, bottle filling stations shall be allowed to be substituted in accordance with Section 2902.5.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-1202Section 1202—Ventilation.
1202.1 General. Buildings shall be provided with natural ventilation in accordance with Section 1203.5, or mechanical ventilation in accordance with the International Mechanical Code. Ambulatory care facilities and Group I-2 occupancies shall be ventilated by mechanical means in accordance with Section 407 of the International Mechanical Code.
1202.2 Attic spaces. Enclosed attics and enclosed rafter spaces formed where ceilings are applied directly to the underside of roof framing members shall have cross ventilation for each separate space by ventilation openings protected against the entrance of rain and snow. Blocking and bridging shall be arranged so as not to interfere with the movement of air. An airspace of not less than 1 inch (25 mm) shall be provided between the insulation and the roof sheathing. The net free ventilating area shall not be less than 1/150th of the area of the space ventilated. Ventilators shall be installed in accordance with the manufacturer's installation instructions.
EXCEPTION:
The net free cross-ventilation area shall be permitted to be reduced to 1/300 provided both of the following conditions are met:
 
1. A Class I or II vapor retarder is installed on the warm-in-winter side of the ceiling.
 
2. At least 40 percent and not more than 50 percent of the required venting area is provided by ventilators located in the upper portion of the attic or rafter space. Upper ventilators shall be located not more than 3 feet (914 mm) below the ridge or highest point of the space, measured vertically, with the balance of the ventilation provided by eave or cornice vents. Where the location of wall or roof framing members conflicts with the installation of upper ventilators, installation more than 3 feet (914 mm) below the ridge or highest point of the space shall be permitted.
1202.4 Under-floor ventilation. The space between the bottom of the floor joists and the earth under any building except spaces occupied by basements or cellars shall be provided with ventilation openings through foundation walls or exterior walls. Such openings shall be placed so as to provide cross ventilation of the under-floor space. A ground cover of six mil (0.006 inch thick) black polyethylene or approved equal shall be laid over the ground within crawl spaces. The ground cover shall be overlapped six inches minimum at the joints and shall extend to the foundation wall.
EXCEPTION:
The ground cover may be omitted in crawl spaces if the crawl space has a concrete slab floor with a minimum thickness of two inches.
1202.5 Natural ventilation. For other than Group R Occupancies, natural ventilation of an occupied space shall be through windows, doors, louvers or other openings to the outdoors. The operating mechanism for such openings shall be provided with ready access so that the openings are readily controllable by the building occupants. Group R Occupancies shall comply with the International Mechanical Code.
((1202.6))1202.7 Radon resistive construction standards. The criteria of this section establishes minimum radon resistive construction requirements for Group R Occupancies.
((1202.6.1))1202.7.1 Application. The requirements of Section 1202.6 shall be adopted and enforced by all jurisdictions of the state according to the following subsections.
((1202.6.1.1))1202.7.1.1 All jurisdictions of the state shall comply with Section 1202.6.2.
((1202.6.1.2))1202.7.1.2 Clark, Ferry, Okanogan, Pend Oreille, Skamania, Spokane, and Stevens counties shall also comply with Section 1203.6.3.
((1202.6.2))1202.7.2 State wide radon requirements.
((1202.6.2.1))1202.7.2.1 Crawlspaces. All crawlspaces shall comply with the requirements of this section.
((1202.6.2.2))1202.7.2.2 Ventilation. All crawlspaces shall be ventilated as specified in Section 1203.3.
If the installed ventilation in a crawlspace is less than one square foot for each 300 square feet of crawlspace area, or if the crawlspace vents are equipped with operable louvers, a radon vent shall be installed to originate from a point between the ground cover and soil. The radon vent shall be installed in accordance with Sections 1203.6.3.2.6 and 1203.6.3.2.7.
((1202.6.2.3))1202.7.2.3 Crawlspace plenum systems. In crawlspace plenum systems used for providing supply air for an HVAC system, aggregate, a permanently sealed soil gas retarder membrane and a radon vent pipe shall be installed in accordance with Section 1203.6.3.2. Crawlspaces shall not be used for return air plenums.
In addition, an operable radon vent fan shall be installed and activated. The fan shall be located as specified in Section 1203.6.3.2.7. The fan shall be capable of providing at least 100 cfm at 1-inch water column static pressure. The fan shall be controlled by a readily accessible manual switch. The switch shall be labeled "RADON VENT FAN."
((1202.6.3))1202.7.3 Radon prescriptive requirements.
((1202.6.3.1))1202.7.3.1 Scope. This section applies to those counties specified in Section 1203.6.1.2. This section establishes prescriptive construction requirements for reducing the potential for radon entry into all Group R Occupancies, and for preparing the building for future mitigation if desired.
In all crawlspaces, except crawlspace plenums used for providing supply air for an HVAC system, a continuous air barrier shall be installed between the crawlspace area and the occupied area to limit air transport between the areas. If a wood sheet subfloor or other material is utilized as an air barrier, in addition to the requirements of Section 502.1.6.2 of the Washington State Energy Code, all joints between sheets shall be sealed.
((1202.6.3.2))1202.7.3.2 Floors in contact with the earth.
((1202.6.3.2.1))1202.7.3.2.1 General. Concrete slabs that are in direct contact with the building envelope shall comply with the requirements of this section.
EXCEPTION:
Concrete slabs located under garages or other than Group R Occupancies need not comply with this chapter.
((1202.6.3.2.2))1202.7.3.2.2 Aggregate. A layer of aggregate of 4-inch minimum thickness shall be placed beneath concrete slabs. The aggregate shall be continuous to the extent practical.
((1202.6.3.2.3))1202.7.3.2.3 Gradation. Aggregate shall:
1. Comply with ASTM Standard C-33 Standard Specification for Concrete Aggregate and shall be size No. 8 or larger size aggregate as listed in Table 2, Grading Requirements for Course Aggregate; or
2. Meet the 1988 Washington State Department of Transportation Specification 9-03.1 (3) "Coarse Aggregate for Portland Cement Concrete," or any equivalent successor standards. Aggregate size shall be of Grade 8 or larger as listed in Section 9-03.1 (3) C, "Grading"; or
3. Be screened, washed pea gravel free of deleterious substances in a manner consistent with ASTM Standard C-33 with 100 percent passing a 1/2-inch sieve and less than 5 percent passing a No. 16 sieve. Sieve characteristics shall conform to those acceptable under ASTM Standard C-33.
EXCEPTION:
Aggregate shall not be required if a substitute material or system, with sufficient load bearing characteristics, and having approved capability to provide equal or superior air flow, is installed.
((1202.6.3.2.4))1202.7.3.2.4 Soil-gas retarder membrane. A soil-gas retarder membrane, consisting of at least one layer of virgin polyethylene with a thickness of at least 6 mil, or equivalent flexible sheet material, shall be either placed directly under all concrete slabs so that the slab is in direct contact with the membrane, or on top of the aggregate with 2 inches minimum of fine sand or pea gravel installed between the concrete slab and membrane. The flexible sheet shall extend to the foundation wall or to the outside edge of the monolithic slab. Seams shall overlap at least 12 inches. The membrane shall also be fitted tightly to all pipes, wires, and other penetrations of the membrane and sealed with an approved sealant or tape. All punctures or tears shall be repaired with the same or approved material and similarly lapped and sealed.
((1202.6.3.2.5))1202.7.3.2.5 Sealing of penetrations and joints. All penetrations and joints in concrete slabs or other floor systems and walls below grade shall be sealed by an approved sealant to create an air barrier to limit the movement of soil-gas into the indoor air.
Sealants shall be approved by the manufacturer for the intended purpose. Sealant joints shall conform to manufacturer's specifications. The sealant shall be placed and tooled in accordance with manufacturer's specifications. There shall be no gaps or voids after the sealant has cured.
((1202.6.3.2.6))1202.7.3.2.6 Radon vent. One continuous sealed pipe shall run from a point within the aggregate under each concrete slab to a point outside the building. Joints and connections shall be permanently gas tight. The continuous sealed pipe shall interface with the aggregate in the following manner, or by other approved equal method. The pipe shall be permanently connected to a "T" within the aggregate area so that the two end openings of the "T" lie within the aggregate area. A minimum of 5 feet of perforated drain pipe of 3 inches minimum diameter shall join to and extend from the "T." The perforated pipe shall remain in the aggregate area and shall not be capped at the ends. The "T" and its perforated pipe extensions shall be located at least 5 feet horizontally from the exterior perimeter of the aggregate area.
The continuous sealed pipe shall terminate no less than 12 inches above the eave, and more than 10 horizontal feet from a woodstove or fireplace chimney, or operable window. The continuous sealed pipe shall be labeled "radon vent." The label shall be placed so as to remain visible to an occupant.
The minimum pipe diameter shall be 3 inches unless otherwise approved. Acceptable sealed plastic pipe shall be smooth walled, and may include either PVC schedule 40 or ABS schedule of equivalent wall thickness.
The entire sealed pipe system shall be sloped to drain to the subslab aggregate.
The sealed pipe system may pass through an unconditioned attic before exiting the building; but to the extent practicable, the sealed pipe shall be located inside the thermal envelope of the building in order to enhance passive stack venting.
EXCEPTION:
A fan for subslab depressurization system includes the following:
 
1. Soil-gas retarder membrane as specified in Section 1203.6.3.2.4;
 
2. Sealing of penetrations and joints as specified in Section 1203.6.3.2.5;
 
3. A 3-inch continuous sealed radon pipe shall run from a point within the aggregate under each concrete slab to a point outside the building;
 
4. Joints and connections shall be gas tight, and may be of either PVC schedule 40 or ABS schedule of equivalent in wall thickness;
 
5. A label of "radon vent" shall be placed on the pipe so as to remain visible to an occupant;
 
6. Fan circuit and wiring as specified in Section 1203.6.3.2.7 and a fan.
If the subslab depressurization system is exhausted through the concrete foundation wall or rim joist, the exhaust terminus shall be a minimum of 6 feet from operable windows or outdoor air intake vents and shall be directed away from operable windows and outdoor air intake vents to prevent radon reentrainment.
((1202.6.3.2.7))1202.7.3.2.7 Fan circuit and wiring and location. An area for location of an in-line fan shall be provided. The location shall be as close as practicable to the radon vent pipe's point of exit from the building, or shall be outside the building shell; and shall be located so that the fan and all downstream piping is isolated from the indoor air.
Provisions shall be made to allow future activation of an in-line fan on the radon vent pipe without the need to place new wiring. A 110 volt power supply shall be provided at a junction box near the fan location.
((1202.6.3.2.8))1202.7.3.2.8 Separate aggregate areas. If the 4-inch aggregate area underneath the concrete slab is not continuous, but is separated into distinct isolated aggregate areas by a footing or other barrier, a minimum of one radon vent pipe shall be installed into each separate aggregate area.
EXCEPTION:
Separate aggregate areas may be considered a single area if a minimum 3-inch diameter connection joining the separate areas is provided for every 30 feet of barrier separating those areas.
((1202.6.3.2.9))1202.7.3.2.9 Concrete block walls. Concrete block walls connected to below grade areas shall be considered unsealed surfaces. All openings in concrete block walls that will not remain accessible upon completion of the building shall be sealed at both vertical and horizontal surfaces, in order to create a continuous air barrier to limit the transport of soil-gas into the indoor air.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-1203Section 1203—Temperature control.
1203.1 Equipment and systems. Interior spaces intended for human occupancy shall be provided with active or passive space-heating systems capable of maintaining an indoor temperature of not less than 68°F (20°C) at a point 3 feet (914 mm) above the floor on the design heating day.
EXCEPTIONS:
1. Interior spaces where the primary purpose of the space is not associated with human comfort.
 
2. Group F, H, S, or U occupancies.
 
3. Group R-1 Occupancies not more than 500 square feet.
((1203.2.1))1203.2 Definitions. For the purposes of this section only, the following definitions apply.
DESIGNATED AREAS are those areas designated by a county to be an urban growth area in chapter 36.70A RCW and those areas designated by the U.S. Environmental Protection Agency as being in nonattainment for particulate matter.
SUBSTANTIALLY REMODELED means any alteration or restoration of a building exceeding 60 percent of the appraised value of such building within a 12-month period. For the purpose of this section, the appraised value is the estimated cost to replace the building and structure in-kind, based on current replacement costs.
((1203.2.2))1203.3 Primary heating source. Primary heating sources in all new and substantially remodeled buildings in designated areas shall not be dependent upon wood stoves.
((1203.2.3))1203.4 Solid fuel burning devices. No new or used solid fuel burning device shall be installed in new or existing buildings unless such device is United States Environmental Protection Agency certified or exempt from certification by the United States Environmental Protection Agency and conforms with RCW 70.94.011, 70.94.450, 70.94.453 and 70.94.457.
EXCEPTIONS:
1. Wood cook stoves.
 
2. Antique wood heaters manufactured prior to 1940.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-1613Section 1613—Earthquake loads.
1613.4 Amendments to ASCE 7. The provisions of Section 1613.4 shall be permitted as an amendment to the relevant provisions of ASCE 7. The text of ASCE 7 shall be amended as indicated in Sections 1613.4.1 through 1613.4.2.
1613.4.1 ASCE 7 Section 12.2.5.4. Amend ASCE 7 Section ((12.11.2.2.1))12.2.5.4 as follows:
12.2.5.4 Increased structural height limit for steel eccentrically braced frames, steel special concentrically braced frames, steel buckling-restrained braced frames, steel special plate shear walls, and special reinforced concrete shear walls. The limits on height, hn, in Table 12.2-1 are permitted to be increased from 160 ft (50 m) to 240 ft (75 m) for structures assigned to Seismic Design Categories D or E and from 100 ft (30 m) to 160 ft (50 m) for structures assigned to Seismic Design Category F, provided that the seismic force-resisting systems are limited to steel eccentrically braced frames, steel special concentrically braced frames, steel buckling-restrained braced frames, steel special plate shear walls, or special reinforced concrete cast-in-place shear walls and all of the following requirements are met:
1. The structure shall not have an extreme torsional irregularity as defined in Table 12.3-1 (horizontal structural irregularity Type 1b).
2. The steel eccentrically braced frames, steel special concentrically braced frames, steel buckling-restrained braced frames, steel special plate shear walls or special reinforced concrete shear walls in any one plane shall resist no more than 60 percent of the total seismic forces in each direction, neglecting accidental torsional effects.
3. Where floor and roof diaphragms transfer forces from the vertical seismic force-resisting elements above the diaphragm to other vertical force-resisting elements below the diaphragm, these in-plane transfer forces shall be amplified by the overstrength factor, Ωo for the design of the diaphragm flexure, shear, and collectors.
4. The earthquake force demands in foundation mat slabs, grade beams, and pile caps supporting braced frames and/or walls arranged to form a shear-resisting core shall be amplified by 2 for shear and 1.5 for flexure. The redundancy factor, ρ, applies and shall be the same as that used for the structure in accordance with Section 12.3.4.
5. The earthquake shear force demands in special reinforced concrete shear walls shall be amplified by the over-strength factor, Ωo.
1613.4.2 ASCE 7 Section 12.6. Amend ASCE 7 Section 12.6 and Table 12.6-1 to read as follows:
12.6 ANALYSIS PROCEDURE SELECTION
12.6.1 Analysis procedure. The structural analysis required by Chapter 12 shall consist of one of the types permitted in Table 12.6-1, based on the structure's seismic design category, structural system, dynamic properties, and regularity, or with the approval of the authority having jurisdiction, an alternative generally accepted procedure is permitted to be used. The analysis procedure selected shall be completed in accordance with the requirements of the corresponding section referenced in Table 12.6-1.
Table 12.6-1
Permitted Analytical Procedures
Seismic Design Category
Structural Characteristics
Equivalent Lateral Force Procedure, Section 12.8a
Modal Response Spectrum Analysis, Section 12.9.1, or Linear Response History Analysis, Section 12.9.2
Nonlinear Response History Procedures, Chapter 16a
B, C
All structures
P
P
P
D, E, F
Risk Category I or II buildings not exceeding two stories above the base
P
P
P
 
Structures of light frame construction
P
P
P
 
Structures with no structural irregularities and not exceeding 160 ft in structural height
P
P
P
 
Structures exceeding 160 ft in structural height with no structural irregularities and with T <3.5Ts
P
P
P
 
Structures not exceeding 160 ft in structural height and having only horizontal irregularities of Type 2, 3, 4, or 5 in Table 12.3-1 or vertical irregularities of Type 4, 5a, or 5b in Table 12.3-2
P
P
P
 
All other structures ≤ 240 ft in height
NP
P
P
 
All structures ˃ 240 ft in height
NP
NP
Pc
a
P: Permitted; NP: Not Permitted; Ts= SD1/SDS.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-21070Section 2107—Allowable stress design.
2107.1 General. The design of masonry structures using allowable stress design shall comply with Sections 2106 and the requirements of Chapters 1 through 8 of TMS 402/ACI 530/ASCE 5 except as modified by Sections 2107.2 through ((2107.4))2107.3.
2107.2 TMS 402/ACI 530/ASCE 5, Section 2.1.8.7.1.1, lap splices. In lieu of Section 2.1.8.7.1.1, it shall be permitted to design lap splices in accordance with Section 2107.2.1.
AMENDATORY SECTION(Amending WSR 13-04-067, filed 2/1/13, effective 7/1/13)
WAC 51-50-2114((Section 2114—Emission standards.))Reserved.
((2114.1 Emission Standards for Factory-built Fireplaces. No new or used factory-built fireplace shall be installed in Washington state unless it is certified and labeled in accordance with procedures and criteria specified in ASTM E2558 Standard Test Method for determining particulate matter emission from fires in low mass wood burning fireplaces.
To certify an entire fireplace model line, the internal assembly shall be tested to determine its particulate matter emission performance. Retesting and recertifying is required if the design and construction specifications of the fireplace model line internal assembly change. Testing for certification shall be performed by a Washington state department of ecology (DOE) approved and U.S. Environmental Protection Agency (EPA) accredited laboratory.
2114.2 Emission Standards for Certified Masonry and Concrete Fireplaces. Masonry and concrete fireplace model lines certified to Washington State Building Code Standard 31-2 prior to July 1, 2013, may retain certification provided the design and construction specifications of the fireplace model line internal assembly do not change.))
NEW SECTION
WAC 51-50-2115Section 2115—Emission standards.
2115.1 Emission standards for factory-built fireplaces. No new or used factory-built fireplace shall be installed in Washington state unless it is certified and labeled in accordance with procedures and criteria specified in ASTM E2558 Standard Test Method for determining particulate matter emission from fires in low mass wood burning fireplaces.
To certify an entire fireplace model line, the internal assembly shall be tested to determine its particulate matter emission performance. Retesting and recertifying is required if the design and construction specifications of the fireplace model line internal assembly change. Testing for certification shall be performed by a Washington state department of ecology (DOE) approved and U.S. Environmental Protection Agency (EPA) accredited laboratory.
2115.2 Emission standards for certified masonry and concrete fireplaces. Masonry and concrete fireplace model lines certified to Washington State Building Code Standard 31-2 prior to July 1, 2013, may retain certification provided the design and construction specifications of the fireplace model line internal assembly do not change.
NEW SECTION
WAC 51-50-2304Section 2304—General construction requirements.
2304.10 Connectors and fasteners. Connectors and fasteners shall comply with the applicable provisions of Sections 2304.10.1 through 2304.10.8.
2304.10.8 Connection fire-resistance rating. Fire-resistance ratings for connections in Type IV-A, IV-B, or IV-C construction shall be determined by one of the following:
1. Testing in accordance with Section 703.2 where the connection is part of the fire-resistance test.
2. Engineering analysis that demonstrates that the temperature rise at any portion of the connection is limited to an average temperature rise of 250°F (139°C), and a maximum temperature rise of 325°F (181°C), for a time corresponding to the required fire-resistance rating of the structural element being connected. For the purposes of this analysis, the connection includes connectors, fasteners, and portions of wood members included in the structural design of the connection.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-2900Chapter 29—Plumbing systems.
SECTION 2901—GENERAL.
2901.1 Scope. The provisions of this chapter and the state plumbing code shall govern the erection, installation, alteration, repairs, relocation, replacement, addition to, use or maintenance of plumbing equipment and systems. Toilet and bathing rooms shall be constructed in accordance with Section 1210. Plumbing systems and equipment shall be constructed, installed and maintained in accordance with the state plumbing code.
2901.2 Health codes. In food preparation, serving and related storage areas, additional fixture requirements may be dictated by health codes.
2901.3 Fixed guideway transit and passenger rail systems. In construction of a fixed guideway and passenger rail system, subject to Section 3114, public plumbing fixtures are not required.
SECTION 2902—MINIMUM PLUMBING FACILITIES.
2902.1 Minimum number of fixtures. Plumbing fixtures shall be provided in the minimum number shown in Table 2902.1. Uses not shown in Table 2902.1 shall be determined individually by the building official based on the occupancy which most nearly resembles the proposed occupancy. The number of occupants shall be determined by this code. Plumbing fixtures need not be provided for unoccupied buildings or facilities.
2902.1.1 Fixture calculations. To determine the occupant load of each sex, the total occupant load shall be divided in half. To determine the required number of fixtures, the fixture ratio or ratios for each fixture type shall be applied to the occupant load of each sex in accordance with Table 2902.1. Fractional numbers resulting from applying the fixture ratios of Table 2902.1 shall be rounded up to the next whole number. For calculations involving multiple occupancies, such fractional numbers for each occupancy shall first be summed and then rounded up to the next whole number.
EXCEPTION:
The total occupant load shall not be required to be divided in half where approved statistical data indicate a distribution of the sexes of other than 50 percent of each sex.
2902.1.1.1 Private offices. Fixtures only accessible to private offices shall not be counted to determine compliance with this section.
2902.1.1.2 Urinals in men's facilities. Where urinals in men's facilities are provided, one water closet less than the number specified may be provided for each urinal installed, except the number of water closets in such cases shall not be reduced to less than one quarter (25%) of the minimum specified. For men's facilities serving 26 or more persons, not less than one urinal shall be provided.
2902.1.1.3 Urinals. Where urinals are provided in gender-neutral facilities, one water closet less than the number specified may be provided for each urinal installed, except the number of water closets in such cases shall not be reduced less than one quarter (25 percent) of the minimum specified. Facilities serving 26 or more persons, not less than one urinal shall be provided.
2902.1.4 Family or assisted-use toilet and bath fixtures. Fixtures located within family or assisted-use toilet and bathing rooms required by Section 1109.2.1 are permitted to be included in the number of required fixtures for either the male or female occupants in assembly and mercantile occupancies.
2902.2Separate facilities. Where plumbing fixtures are required, separate facilities shall be provided for each sex.
EXCEPTIONS:
1. Separate facilities shall not be required for dwelling units and sleeping units.
 
2. Separate facilities shall not be required in structures or tenant spaces with a total occupant load, including both employees and customers, of 15 or less.
 
3. Separate facilities shall not be required in mercantile occupancies in which the maximum occupant load is 100 or less.
 
4. Separate facilities shall not be required in spaces primarily used for drinking or dining with a total occupant load, including both employees and customers, of 30 or fewer.
 
5. Separate facilities shall not be required when gender-neutral facilities are provided in accordance with Section 2902.2.2.
2902.2.1Family or assisted-use toilet facilities serving as separate facilities. Where a building or tenant space requires a separate toilet facility for each sex and each toilet facility is required to have only one water closet, two family or assisted-use toilet facilities shall be permitted to serve as the required separate facilities. Family or assisted-use toilet facilities shall not be required to be identified for exclusive use by either sex as required by Section 2902.4.
2902.2.2 Gender-neutral facilities. Gender-neutral toilet facilities, when provided, shall be in accordance with the following:
1. There is no reduction in the number of fixtures required to be provided for male and female in the type of occupancy and in the minimum number shown in Table 2902.1.
2. Gender-neutral multiuser toilet rooms shall have water closets and urinals located in toilet compartments in accordance with ICC A117.1.
3. Gender-neutral multiuser toilet room water closet and urinal compartments shall have full-height walls and a door enclosing the fixture to ensure privacy.
4. Gender-neutral toilet room water closet and urinal compartment doors shall be securable from within the compartment.
5. Gender-neutral toilet rooms provided for the use of multiple occupants, the egress door from the room shall not be lockable from the inside of the room.
6. Compartments shall not be required in a single-occupant toilet room with a lockable door.
2902.3 Employee and public toilet facilities. Customers, patrons and visitors shall be provided with public toilet facilities in structures and tenant spaces intended for public utilization. The number of plumbing fixtures located within the required toilet facilities shall be provided in accordance with Section 2902.1 for all users. Employees shall be provided with toilet facilities in all occupancies. Employee toilet facilities shall either be separate or combined employee and public toilet facilities.
EXCEPTION:
Public toilet facilities shall not be required in:
 
1. Open or enclosed parking garages where there are no parking attendants.
 
2. Structures and tenant spaces intended for quick transactions, including takeout, pickup and drop-off, having a public access area less than or equal to 300 square feet (28 m2).
 
3. Fixed guideway transit and passenger rail systems constructed in accordance with Section 3112.
2902.3.2 Location of toilet facilities in occupancies other than malls. In occupancies other than covered and open mall buildings, the required public and employee toilet facilities shall be located in each building not more than one story above or below the space required to be provided with toilet facilities, or conveniently in a building adjacent thereto on the same property, and the path of travel to such facilities shall not exceed a distance of 500 feet (152 m).
EXCEPTION:
The location and maximum distances of travel to required employee facilities in factory and industrial occupancies are permitted to exceed that required by this section, provided that the location and maximum distance of travel are approved.
2902.3.3 Location of toilet facilities in malls. In covered and open mall buildings, the required public and employee toilet facilities shall be located not more than one story above or below the space required to be provided with toilet facilities, and the path of travel to such facilities shall not exceed a distance of 300 feet (91,440 mm). In mall buildings, the required facilities shall be based on total square footage (m2) within a covered mall building or within the perimeter line of an open mall building, and facilities shall be installed in each individual store or in a central toilet area located in accordance with this section. The maximum distance of travel to central toilet facilities in mall buildings shall be measured from the main entrance of any store or tenant space. In mall buildings, where employees' toilet facilities are not provided in the individual store, the maximum distance of travel shall be measured from the employees' work area of the store or tenant space.
2902.3.4 Pay facilities. Where pay facilities are installed, such facilities shall be in excess of the required minimum facilities. Required facilities shall be free of charge.
2902.3.5 Door locking. Where a toilet room is provided for the use of multiple occupants, the egress door for the room shall not be lockable from the inside of the room. This section does not apply to family or assisted-use toilet rooms.
2902.3.6 Prohibited toilet room location. Toilet rooms shall not open directly into a room used for the preparation of food for service to the public.
2902.4 Signage. Required public facilities shall be provided with signs that designate the sex for separate facilities or indicate gender-neutral facilities. Signs shall be readily visible and located near the entrance to each toilet facility. Signs for accessible toilet facilities shall comply with Section 1111.
2902.4.1 Directional signage. Directional signage indicating the route to the public toilet facilities shall be posted in a lobby, corridor, aisle or similar space, such that the sign can be readily seen from the main entrance to the building or tenant space.
2902.5 Drinking fountain location. Drinking fountains shall not be required to be located in individual tenant spaces provided that public drinking fountains are located within a distance of travel of 500 feet of the most remote location in the tenant space and not more than one story above or below the tenant space. Where the tenant space is in a covered or open mall, such distance shall not exceed 300 feet. Drinking fountains shall be located on an accessible route. Drinking fountains shall not be located in toilet rooms.
2902.5.1 Drinking fountain number. Occupant loads over 30 shall have one drinking fountain for the first 150 occupants, then one per each additional 500 occupants.
EXCEPTIONS:
1. Sporting facilities with concessions serving drinks shall have one drinking fountain for each 1000 occupants.
 
2. A drinking fountain need not be provided in a drinking or dining establishment.
2902.5.2 Multistory buildings. Drinking fountains shall be provided on each floor having more than 30 occupants in schools, dormitories, auditoriums, theaters, offices and public buildings.
2902.5.3 Penal institutions. Penal institutions shall have one drinking fountain on each cell block floor and one on each exercise floor.
2902.5.4 Bottle filling stations. Bottle filling stations shall be provided in accordance with Sections 2902.5.4.1 through 2902.5.4.3.
2902.5.4.1 Group E occupancies. In Group E occupancies with an occupant load over 30, a minimum of one bottle filling station shall be provided on each floor. This bottle filling station may be integral to a drinking fountain.
2902.5.4.2 Substitution. In all occupancies that require more than two drinking fountains per floor or secured area, bottle filling stations shall be permitted to be substituted for up to 50 percent of the required number of drinking fountains.
2902.5.4.3 Accessibility. At least one of the required bottle filling stations shall be located in accordance with Section 309 ICC A117.1.
2902.6 Dwelling units. Dwelling units shall be provided with a kitchen sink.
((2902.8))2902.7 Water. Each required sink, lavatory, bathtub and shower stall shall be equipped with hot and cold running water necessary for its normal operation.
SECTION 2903—RESERVED.
SECTION 2904—RESERVED.
Table 2902.1
Minimum Number of Required Plumbing Fixturesa
(See Sections 2902.2 and 2902.3)
No.
Classification
Occupancy
Description
Water Closets
Lavatories
Bathtubs/
Showers
Male
Female
Male
Female
1
Assembly
A-1d
Theaters and other buildings for the performing arts and motion pictures
1 per 125
1 per 65
1 per 200
—
 
 
A-2d
Nightclubs, bars, taverns, dance halls and buildings for similar purposes
1 per 40
1 per 40
1 per 75
—
 
 
Restaurants, banquet halls and food courts
1 per 75
1 per 75
1 per 200
—
 
 
A-3d
Auditoriums without permanent seating, art galleries, exhibition halls, museums, lecture halls, libraries, arcades and gymnasiums
1 per 125
1 per 65
1 per 200
—
 
 
 
Passenger terminals and transportation facilities
1 per 500
1 per 500
1 per 750
—
 
 
 
Places of worship and other religious services
1 per 150
1 per 75
1 per 200
—
 
 
A-4
Coliseums, arenas, skating rinks, pools, and tennis courts for indoor sporting events and activities
1 per 75 for first 1,500 and 1 per 120 for remainder exceeding 1,500
1 per 40 for first 1,520 and 1 per 60 for remainder exceeding 1,520
1 per 200
1 per 150
—
 
 
A-5
Stadiums amusement parks, bleachers and grandstands for outdoor sporting events and activities
1 per 75 for first 1,500 and 1 per 120 for remainder exceeding 1,500
1 per 40 for first 1,520 and 1 per 60 for remainder exceeding 1,520
1 per 200
1 per 150
—
2
Business
B
Buildings for the transaction of business, professional services, other services involving merchandise, office buildings, banks, light industrial and similar uses
1 per 25 for first 50 and 1 per 50 for the remainder exceeding 50
1 per 40 for first 80 and 1 per 80 for remainder exceeding 80
—
3
Educational
Ee
Educational facilities
1 per 35
1 per 25
1 per 85
1 per 50
—
4
Factory and industrial
F-1 and F-2
Structures in which occupants are engaged in work fabricating, assembly or processing of products or materials
1 per 100
1 per 100
Check State (UPC)
5
Institutional
I-1
Residential care
1 per 10
1 per 10
1 per 8
 
 
I-2
Hospitals, ambulatory nursing home care recipientb
1 per roomc
1 per roomc
1 per 15
 
 
 
Employees, other than residential careb
1 per 25
1 per 35
—
 
 
 
Visitors other than residential care
1 per 75
1 per 100
—
 
 
I-3
Prisonsb
1 per cell
1 per cell
1 per 15
 
 
 
Reformatories, detention centers and correctional centersb
1 per 15
1 per 15
1 per 15
 
 
 
Employeesb
1 per 25
1 per 35
—
 
 
I-4
Adult day care and child day care
1 per 15
1 per 15
1
6
Mercantile
M
Retail stores, service stations, shops, salesrooms, markets and shopping centers
1 per 500
1 per 750
—
7
Residential
R-1
Hotels, motels, boarding houses (transient)
1 per sleeping unit
1 per sleeping unit
1 per sleeping unit
 
 
R-2
Dormitories, fraternities, sororities and boarding houses (not transient)
1 per 10
1 per 10
1 per 8
 
 
 
Apartment house
1 per dwelling unit
1 per dwelling unit
1 per dwelling unit
 
 
R-3
One- and two-family dwellings
1 per dwelling unit
1 per 10
1 per dwelling unit
 
 
 
Congregate living facilities with 16 or fewer persons
1 per 10
1 per 10
1 per 8
 
 
R-4
Congregate living facilities with 16 or fewer persons
1 per 10
1 per 10
1 per 8
8
Storage
S-1
S-2
Structures for the storage of goods, warehouses, storehouses and freight depots, low and moderate hazard
1 per 100
1 per 100
Check State (UPC)
a.
The fixtures shown are based on one fixture being the minimum required for the number of persons indicated or any fraction of the number of persons indicated. The number of occupants shall be determined by this code, except with respect to Group E occupancies the provisions of note "e" shall apply.
b.
Toilet facilities for employees shall be separate from facilities for inmates or care recipients.
c.
A single-occupant toilet room with one water closet and one lavatory serving not more than two adjacent patient sleeping units shall be permitted where such room is provided with direct access from each patient sleeping unit and with provisions for privacy.
d.
The occupant load for seasonal outdoor seating and entertainment areas shall be included when determining the minimum number of facilities required.
e.
For Group E occupancies: The number of occupants shall be determined by using a calculation of 100 square feet gross building area per student for the minimum number of plumbing fixtures.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-30050Section ((30050))3005—Machine rooms.
((30050.2))3005.2 Temperature control. Elevator machine rooms, machinery spaces that contain the driving machine, and control rooms or spaces that contain the operation or motion controller for elevator operation shall be provided with an independent dedicated ventilation or air-conditioning system to control the space temperature to protect against the overheating of the electrical equipment. Ventilation systems shall use outdoor make up air pathway that does not rely on transfer air from other building systems. The system shall service the equipment space only, and shall be capable of maintaining the temperature and humidity within the range established by the manufacturer's specifications. Where no manufacturer specifications are available, the equipment space temperature shall be maintained at no less than fifty-five degrees Fahrenheit and no more than ninety degrees Fahrenheit.
The cooling load for the equipment shall include the BTU output of the elevator operation equipment as specified by the manufacturer based on one hour of continuous operation. The outdoor design temperature for ventilation shall be from the 0.5% column for summer from the Puget Sound Chapter of ASHRAE publication "Recommended Outdoor Design Temperatures, Washington State." The following formula shall be used to calculate flow rate for ventilation:
CFM = BTU output of elevator machine room equipment/[1.08 x (acceptable machine room temp - make up air temp)]
The ventilation or air-conditioning system will be provided with the same source of power (normal, optional standby, legally required standby, or emergency) as the elevator equipment so that the temperature control is available at all times that the elevators have power.
EXCEPTION:
For buildings four stories or less, natural or mechanical means may be used in lieu of an independent ventilation or air-conditioning system to keep the equipment space ambient air temperature and humidity in the range specified by the elevator equipment manufacturer.
Reviser's note: The brackets and enclosed material in the text of the above section occurred in the copy filed by the agency and appear in the Register pursuant to the requirements of RCW 34.08.040.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-3500Chapter 35—Referenced standards.
Add the reference standards as follows:
Standard reference number
Title
Referenced in code section number
ANSI/APA PRG-320-18
Standard for Performance-Rated Cross-Laminated Timber (revised 2018)
602.4, 2303.1.4
NFPA ((130))130-17
Standard for Fixed Guideway Transit and Passenger Rail Systems
3101.1, 3114
NEW SECTION
WAC 51-50-480200Section 201.3—Definitions.
201.3 Terms defined in other codes. Where terms are not defined in this code and are defined in the other International Codes and the Uniform Plumbing Code, such terms shall have the meanings ascribed to them in those codes.
AMENDATORY SECTION(Amending WSR 10-03-097, filed 1/20/10, effective 7/1/10)
WAC 51-50-480302((Reserved.))Section 302—General Provisions.
302.3 Additional codes. Alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and structures shall comply with the provisions for alterations, repairs, additions and changes of occupancy or relocation, respectively, in this code and the Washington State Energy Code, International Fire Code, International Fuel Gas Code, International Mechanical Code, Uniform Plumbing Code, and International Residential Code. Where provisions of the other codes conflict with provisions of this code, the provisions of this code shall take precedence.
NEW SECTION
WAC 51-50-480408Section 408—Plumbing.
408.1 Materials. Plumbing materials and supplies shall not be used for repairs that are prohibited in the Uniform Plumbing Code.
AMENDATORY SECTION(Amending WSR 10-03-097, filed 1/20/10, effective 7/1/10)
WAC 51-50-480506((Reserved.))Section 506—Change of occupancy.
506.1.1 Change in the character of use. A change of occupancy with no change of occupancy classification shall not be made to any structure that will subject the structure to any special provisions of the applicable International Codes and Uniform Plumbing Code, without approval of the code official. Compliance shall be only as necessary to meet the specific provisions and is not intended to require the entire building be brought into compliance.
NEW SECTION
WAC 51-50-480702Section 702—Building elements and materials.
702.6 Materials and methods. New work shall comply with the materials and methods requirements in the International Building Code, Washington State Energy Code, International Mechanical Code, and Uniform Plumbing Code, as applicable, that specify material standards, detail of installation and connection, joints, penetrations, and continuity of any element, component, or system in the building.
NEW SECTION
WAC 51-50-480809Section 809—Plumbing.
809.1 Minimum fixtures. Where the occupant load of the story is increased by more than 20 percent, plumbing fixtures for the story shall be provided in quantities specified in the International Building Code based on the increased occupant load.
NEW SECTION
WAC 51-50-481009Section 1009—Plumbing.
1009.1 Increased demand. Where the occupancy of an existing building or part of an existing building is changed such that the new occupancy is subject to increased or different plumbing fixture requirements or to increased water supply requirements in accordance with the Uniform Plumbing Code, the new occupancy shall comply with the intent of the respective Uniform Plumbing Code provisions.
1009.2 Food-handling occupancies. If the new occupancy is a food-handling establishment, all existing sanitary waste lines above the food or drink preparation or storage areas shall be panned or otherwise protected to prevent leaking pipes or condensation on pipes from contaminating food or drink. New drainage lines shall not be installed above such areas and shall be protected in accordance with the Uniform Plumbing Code.
1009.3 Interceptor required. If the new occupancy will produce grease or oil-laden wastes, interceptors shall be provided as required in the Uniform Plumbing Code.
1009.5 Group I-2. If the occupancy group is changed to Group I-2, the plumbing system shall comply with the applicable requirements of the Uniform Plumbing Code.
AMENDATORY SECTION(Amending WSR 13-04-067, filed 2/1/13, effective 7/1/13)
WAC 51-50-481101((Chapter 11—Reserved.))Section 1101—Change of occupancy classification.
1101.1 Scope. An addition to a building or structure shall comply with the International Codes and Uniform Plumbing Code as adopted for new construction without requiring the existing building or structure to comply with any requirements of those codes or of these provisions, except as required by this chapter. Where an addition impacts the existing building or structure, that portion shall comply with this code.
AMENDATORY SECTION(Amending WSR 20-01-090, filed 12/12/19, effective 7/1/20)
WAC 51-50-481204((Change of occupancy.))Reserved.
((1204.1 General. Historic buildings shall comply with the applicable structural provisions for the work as classified in Chapter 4 or 5.
EXCEPTION:
The code official shall be authorized to accept existing floors and existing live loads and to approve operational controls that limit the live load on any floor.
1204.10 One-hour fire-resistant assemblies. Where one-hour fire-resistance-rated construction is required by these provisions, it need not be provided, regardless of construction or occupancy, where the existing wall and ceiling finish is wood lath or metal lath and plaster.
1204.14 Natural light. When it is determined by the professional responsible for the historical documentation of the project that compliance with the natural light requirements of Section 1011.1 will lead to loss of historic character or historic materials in the building, the existing level of natural lighting shall be considered acceptable.))
AMENDATORY SECTION(Amending WSR 10-03-097, filed 1/20/10, effective 7/1/10)
WAC 51-50-481500((Reserved.))Section 1501—General.
1501.1 Facilities required. Sanitary facilities shall be provided during construction or demolition activities in accordance with the Uniform Plumbing Code.