(Effective until July 1, 2023)
Section 506—Building area.
Table 506.2
Allowable Area Factor (At = NS, S1, S13R, S13D or SM, as applicable) In Square Feeta,b
Occupancy Classification | See Footnotes | Type of Construction |
Type I | Type II | Type III | Type IV | Type V |
A | B | A | B | A | B | A | B | C | HT | A | B |
A-1 | NS | UL | UL | 15,500 | 8,500 | 14,000 | 8,500 | 45,000 | 30,000 | 18,750 | 15,000 | 11,500 | 5,500 |
S1 | UL | UL | 62,000 | 34,000 | 56,000 | 34,000 | 180,000 | 120,000 | 75,000 | 60,000 | 46,000 | 22,000 |
SM | UL | UL | 46,500 | 25,500 | 42,000 | 25,500 | 135,000 | 90,000 | 56,250 | 45,000 | 34,500 | 16,500 |
A-2 | NS | UL | UL | 15,500 | 9,500 | 14,000 | 9,500 | 45,000 | 30,000 | 18,750 | 15,000 | 11,500 | 6,000 |
S1 | UL | UL | 62,000 | 38,000 | 56,000 | 38,000 | 180,000 | 120,000 | 75,000 | 60,000 | 46,000 | 24,000 |
SM | UL | UL | 46,500 | 28,500 | 42,000 | 28,500 | 135,000 | 90,000 | 56,250 | 45,000 | 34,500 | 18,000 |
A-3 | NS | UL | UL | 15,500 | 9,500 | 14,000 | 9,500 | 45,000 | 30,000 | 18,750 | 15,000 | 11,500 | 6,000 |
S1 | UL | UL | 62,000 | 38,000 | 56,000 | 38,000 | 180,000 | 120,000 | 75,000 | 60,000 | 46,000 | 24,000 |
SM | UL | UL | 46,500 | 28,500 | 42,000 | 28,500 | 135,000 | 90,000 | 56,250 | 45,000 | 34,500 | 18,000 |
A-4 | NS | UL | UL | 15,500 | 9,500 | 14,000 | 9,500 | 45,000 | 30,000 | 18,750 | 15,000 | 11,500 | 6,000 |
S1 | UL | UL | 62,000 | 38,000 | 56,000 | 38,000 | 180,000 | 120,000 | 75,000 | 60,000 | 46,000 | 24,000 |
SM | UL | UL | 46,500 | 28,500 | 42,000 | 28,500 | 135,000 | 90,000 | 56,250 | 45,000 | 34,500 | 18,000 |
A-5 | NS | UL | UL | UL | UL | UL | UL | UL | UL | UL | UL | UL | UL |
S1 | | | | | | | | | | | | |
SM | | | | | | | | | | | | |
B | NS | UL | UL | 37,500 | 23,000 | 28,500 | 19,000 | 108,000 | 72,000 | 45,000 | 36,000 | 18,000 | 9,000 |
S1 | UL | UL | 150,000 | 92,000 | 114,000 | 76,000 | 432,000 | 288,000 | 180,000 | 144,000 | 72,000 | 36,000 |
SM | UL | UL | 112,500 | 69,000 | 85,500 | 57,000 | 324,000 | 216,000 | 135,000 | 108,000 | 54,000 | 27,000 |
E | NS | UL | UL | 26,500 | 14,500 | 23,500 | 14,500 | 76,500 | 51,000 | 31,875 | 25,500 | 18,500 | 9,500 |
S1 | UL | UL | 106,000 | 58,000 | 94,000 | 58,000 | 306,000 | 204,000 | 127,500 | 102,000 | 74,000 | 38,000 |
SM | UL | UL | 79,500 | 43,500 | 70,500 | 43,500 | 229,500 | 153,000 | 95,625 | 76,500 | 55,500 | 28,500 |
F-1 | NS | UL | UL | 25,000 | 15,500 | 19,000 | 12,000 | 100,500 | 67,000 | 41,875 | 33,500 | 14,000 | 8,500 |
S1 | UL | UL | 100,000 | 62,000 | 76,000 | 48,000 | 402,000 | 268,000 | 167,500 | 134,000 | 56,000 | 34,000 |
SM | UL | UL | 75,000 | 46,500 | 57,000 | 36,000 | 301,500 | 201,000 | 125,625 | 100,500 | 42,000 | 25,500 |
F-2 | NS | UL | UL | 37,500 | 23,000 | 28,500 | 18,000 | 151,500 | 101,000 | 63,125 | 50,500 | 21,000 | 13,000 |
S1 | UL | UL | 150,000 | 92,000 | 114,000 | 72,000 | 606,000 | 404,000 | 252,500 | 202,000 | 84,000 | 52,000 |
SM | UL | UL | 112,500 | 69,000 | 85,500 | 54,000 | 454,500 | 303,000 | 189,375 | 151,500 | 63,000 | 39,000 |
H-1 | NSc | 21,000 | 16,500 | 11,000 | 7,000 | 9.500 | 7,000 | 10,500 | 10,500 | 10,000 | 10,500 | 7,500 | NP |
S1 | | | | | | | | | | | | |
H-2 | NSc | 21,000 | 16,500 | 11,000 | 7,000 | 9.500 | 7,000 | 10,500 | 10,500 | 10,000 | 10,500 | 7,500 | 3,000 |
S1 | | | | | | | | | | | | |
SM | | | | | | | | | | | | |
H-3 | NSc | UL | 60,000 | 26,500 | 14,000 | 17,500 | 13,000 | 25,500 | 25,500 | 25,500 | 25,500 | 10,000 | 5,000 |
S1 | | | | | | | | | | | | |
SM | | | | | | | | | | | | |
H-4 | NSc,d | UL | UL | 37,500 | 17,500 | 28,500 | 17,500 | 72,000 | 54,000 | 40,500 | 36,000 | 18,000 | 6,500 |
S1 | UL | UL | 150,000 | 70,000 | 114,000 | 70,000 | 288,000 | 216,000 | 162,000 | 144,000 | 72,000 | 26,000 |
SM | UL | UL | 112,500 | 52,500 | 85,500 | 52,500 | 216,000 | 162,000 | 121,500 | 108,000 | 54,000 | 19,500 |
H-5 | NSc,d | UL | UL | 37,500 | 23,000 | 28,500 | 19,000 | 72,000 | 54,000 | 40,500 | 36,000 | 18,000 | 9,000 |
S1 | UL | UL | 150,000 | 92,000 | 114,000 | 76,000 | 288,000 | 216,000 | 162,000 | 144,000 | 72,000 | 36,000 |
SM | UL | UL | 112,500 | 69,000 | 85,500 | 57,000 | 216,000 | 162,000 | 121,500 | 108,000 | 54,000 | 27,000 |
Occupancy Classification | See Footnotes | Type of Construction |
Type I | Type II | Type III | Type IV | Type V |
A | B | A | B | A | B | A | B | C | HT | A | B |
I-1 | NSd, e | UL | 55,000 | 19,000 | 10,000 | 16,500 | 10,000 | 54,000 | 36,000 | 18,000 | 18,000 | 10,500 | 4,500 |
S1 | UL | 220,000 | 76,000 | 40,000 | 66,000 | 40,000 | 216,000 | 144,000 | 72,000 | 72,000 | 42,000 | 18,000 |
SM | UL | 165,000 | 57,000 | 30,000 | 49,500 | 30,000 | 162,000 | 108,000 | 54,000 | 54,000 | 31,500 | 13,500 |
I-2 | NSd, f | UL | UL | 15,000 | 11,000 | 12,000 | NP | 36,000 | 24,000 | 12,000 | 12,000 | 9,500 | NP |
S1 | UL | UL | 60,000 | 44,000 | 48,000 | NP | 144,000 | 96,000 | 48,000 | 48,000 | 38,000 | NP |
SM | UL | UL | 45,000 | 33,000 | 36,000 | NP | 108,000 | 72,000 | 36,000 | 36,000 | 28,500 | NP |
I-3 | NSd, e | UL | UL | 15,000 | 10,000 | 10,500 | 7,500 | 36,000 | 24,000 | 12,000 | 12,000 | 7,500 | 5,000 |
S1 | UL | UL | 45,000 | 40,000 | 42,000 | 30,000 | 144,000 | 96,000 | 48,000 | 48,000 | 30,000 | 20,000 |
SM | UL | UL | 45,000 | 30,000 | 31,500 | 22,500 | 108,000 | 72,000 | 36,000 | 36,000 | 22,500 | 15,000 |
I-4 | NSd, g | UL | 60.500 | 26,500 | 13,000 | 23,500 | 13,000 | 76,500 | 51,000 | 25,500 | 25,500 | 18,500 | 9,000 |
S1 | UL | 121,000 | 106,000 | 52,000 | 94,000 | 52,000 | 306,000 | 204,000 | 102,000 | 102,000 | 74,000 | 36,000 |
SM | UL | 181,500 | 79,500 | 39,000 | 70,500 | 39,000 | 229,500 | 153,000 | 76,500 | 76,500 | 55,500 | 27,000 |
M | NS | UL | UL | 21,500 | 12,500 | 18,500 | 12,500 | 61,500 | 41,000 | 25,625 | 20,500 | 14,000 | 9,000 |
S1 | UL | UL | 86,000 | 50,000 | 74,000 | 50,000 | 246,000 | 164,000 | 102,500 | 82,000 | 56,000 | 36,000 |
SM | UL | UL | 64,500 | 37,500 | 55,500 | 37,500 | 184,500 | 123,000 | 76,875 | 61,500 | 42,000 | 27,000 |
R-1h | NSd | UL | UL | 24,000 | 16,000 | 24,000 | 16,000 | 61,500 | 41,000 | 25,625 | 20,500 | 12,000 | 7,000 |
S13R | | | | | | | | | | | | |
S1 | UL | UL | 96,000 | 64,000 | 96,000 | 64,000 | 246,000 | 164,000 | 102,500 | 82,000 | 48,000 | 28,000 |
SM | UL | UL | 72,000 | 48,000 | 72,000 | 48,000 | 184,500 | 123,000 | 76,875 | 61,500 | 36,000 | 21,000 |
R-2h | NSd | UL | UL | 24,000 | 16,000 | 24,000 | 16,000 | 61,500 | 41,000 | 25.625 | 20,500 | 12,000 | 7,000 |
S13R |
S1 | UL | UL | 96,000 | 64,000 | 96,000 | 64,000 | 246,000 | 164,000 | 102,500 | 82,000 | 48,000 | 28,000 |
SM | UL | UL | 72,000 | 48,000 | 72,000 | 48,000 | 184,500 | 123,000 | 76,875 | 61,500 | 36,000 | 21,000 |
R-3h | NSd | UL | UL | UL | UL | UL | UL | UL | UL | UL | UL | UL | UL |
S13D | | | | | | | | | | | | |
S13R | | | | | | | | | | | | |
S1 | | | | | | | | | | | | |
SM | | | | | | | | | | | | |
R-4h | NSd | UL | UL | 24,000 | 16,000 | 24,000 | 16,000 | 61,500 | 41,000 | 25,625 | 20,500 | 12,000 | 7,000 |
S13D | | | | | | | | | | | | |
S13R | | | | | | | | | | | | |
S1 | UL | UL | 96,000 | 64,000 | 96,000 | 64,000 | 246,000 | 164,000 | 102,500 | 82,000 | 48,000 | 28,000 |
SM | UL | UL | 72,000 | 48,000 | 72,000 | 48,000 | 184,500 | 123,000 | 76,875 | 61,500 | 36,000 | 21,000 |
S-1 | NS | UL | 48,000 | 26,000 | 17,500 | 26,000 | 17,500 | 76,500 | 51,000 | 31,875 | 25,500 | 14,000 | 9,000 |
S1 | UL | 192,000 | 104,000 | 70,000 | 104,000 | 70,000 | 306,000 | 204,000 | 127,500 | 102,000 | 56,000 | 36,000 |
SM | UL | 144,000 | 78,000 | 52,500 | 78,000 | 52,500 | 229,500 | 153,000 | 95,625 | 76,500 | 42,000 | 27,000 |
S-2 | NS | UL | 79,000 | 39,000 | 26,000 | 39,000 | 26,000 | 115,500 | 77,000 | 48,125 | 38,500 | 21,000 | 13,500 |
S1 | UL | 316,000 | 156,000 | 104,000 | 156,000 | 104,000 | 462,000 | 308,000 | 192,500 | 154,000 | 84,000 | 54,000 |
SM | UL | 237,000 | 117,000 | 78,000 | 117,000 | 78,000 | 346,500 | 231,000 | 144,375 | 115,500 | 63,000 | 40,500 |
U | NSi | UL | 35,500 | 19,000 | 8,500 | 14,000 | 8,500 | 54,000 | 36,000 | 22,500 | 18,000 | 9,000 | 5,500 |
S1 | UL | 142,000 | 76,000 | 34,000 | 56,000 | 34,000 | 216,000 | 144,000 | 90,000 | 72,000 | 36,000 | 22,000 |
SM | UL | 106,500 | 57,000 | 25,500 | 42,000 | 25,500 | 162,000 | 108,000 | 67,500 | 54,000 | 27,000 | 16,500 |
For SI: 1 square foot = 0.0929 m2. |
UL = Unlimited; NP = Not permitted; NS = Buildings not equipped throughout with an automatic sprinkler system; S1 = Buildings a maximum of one story above grade plane equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; SM = Buildings two or more stories above grade plane equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2; S13D = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.3. |
| a | See Chapters 4 and 5 for specific exceptions to the allowable height in this chapter. |
| b | See Section 903.2 for the minimum thresholds for protection by an automatic sprinkler system for specific occupancies. |
| c | New Group H occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.5. |
| d | The NS value is only for use in evaluation of existing building area in accordance with the International Existing Building Code. |
| e | New Group I-1 and I-3 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6. For new Group I-1 occupancies Condition 1, see Exception 1 of Section 903.2.6. |
| f | New and existing Group I-2 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6 and Section 1103.5 of the International Fire Code. |
| g | For new Group I-4 occupancies, see Exceptions 2 and 3 of Section 903.2.6. |
| h | New Group R occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.8. |
| i | The maximum allowable area for a single-story nonsprinklered Group U greenhouse is permitted to be 9,000 square feet, or the allowable area shall be permitted to comply with Table C102.1 of Appendix C. |
[Statutory Authority: RCW
19.27.031 and
19.27.074. WSR 20-01-090, § 51-50-0506, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-0506, filed 12/26/18, effective 7/1/19; WSR 16-03-064, § 51-50-0506, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW
19.27.031 and chapters
19.27 and
34.05 RCW. WSR 13-04-067, § 51-50-0506, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW
19.27.031 and
19.27.074. WSR 10-03-097, § 51-50-0506, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW
19.27.074,
19.27.020, and chapters
70.92, 19.27, and
34.05 RCW. WSR 07-01-091, § 51-50-0506, filed 12/19/06, effective 7/1/07.]
(Effective July 1, 2023)
Reserved.
[Statutory Authority: RCW
19.27.031 and
19.27.074. WSR 22-13-094, § 51-50-0506, filed 6/14/22, effective 7/1/23; WSR 20-01-090, § 51-50-0506, filed 12/12/19, effective 7/1/20; WSR 19-02-038, § 51-50-0506, filed 12/26/18, effective 7/1/19; WSR 16-03-064, § 51-50-0506, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW
19.27.031 and chapters
19.27 and
34.05 RCW. WSR 13-04-067, § 51-50-0506, filed 2/1/13, effective 7/1/13. Statutory Authority: RCW
19.27.031 and
19.27.074. WSR 10-03-097, § 51-50-0506, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW
19.27.074,
19.27.020, and chapters
70.92, 19.27, and
34.05 RCW. WSR 07-01-091, § 51-50-0506, filed 12/19/06, effective 7/1/07.]
