Table C402.4—Building envelope requirements—Fenestration.
Table C402.4
Building Envelope Fenestration Maximum U-factor and SHGC Requirements
CLIMATE ZONE | 5 AND MARINE 4 |
U-factor for Class AW windows rated in accordance with AAMA/CSA101/I.S.2/A440, vertical curtain walls and site-built fenestration productsa |
FixedbU-factor | U-0.34 |
OperablecU-factor | U-0.36 |
Entrance doorsd |
U-factor | U-0.60 |
U-factor for all other vertical fenestration |
Fixed U-factor | U-0.26 |
Operable or mulled windows with fixed and operable sections U-factor | U-0.28 |
SHGC for all vertical fenestrationf |
| Fixed | Operable |
PF < 0.2 | 0.38 | 0.33 |
0.2 ≤ PF < 0.5 | 0.46 | 0.40 |
PF ≥ 0.5 | 0.61 | 0.53 |
Skylights |
U-factor | U-0.50 |
SHGC | 0.35 |
a | U-factor and SHGC shall be rated in accordance with NFRC 100. |
b | "Fixed" includes curtain wall, storefront, picture windows, and other fixed windows. |
c | "Operable" includes openable fenestration products other than "entrance doors." |
d | "Entrance door" includes glazed swinging entrance doors. Other doors which are not entrance doors, including sliding glass doors, are considered "operable." |
e | Reserved. |
f | Fenestration that is entirely within the conditioned space or is between conditioned and other enclosed space is exempt from solar heat gain coefficient requirements and not included in the SHGC calculation. |
[Statutory Authority: RCW
19.27A.045 and chapter
19.27A RCW. WSR 24-16-145, § 51-11C-402300, filed 8/7/24, effective 9/7/24. Statutory Authority: RCW
19.27A.020,
19.27A.025,
19.27A.160 and chapters
19.27A and
19.27 RCW. WSR 22-14-091, 23-12-101, and 23-20-021, § 51-11C-402300, filed 7/1/22, 6/7/23, and 9/25/23, effective 3/15/24. Statutory Authority: RCW
19.27A.020,
19.27A.025,
19.27A.160 and chapter
19.27 RCW. WSR 19-24-040, § 51-11C-402300, filed 11/26/19, effective 7/1/20. Statutory Authority: RCW
19.27A.025,
19.27A.160, and
19.27.074. WSR 16-03-072, § 51-11C-402300, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW
19.27A.020,
19.27A.025 and chapters
19.27 and
34.05 RCW. WSR 13-04-056, § 51-11C-402300, filed 2/1/13, effective 7/1/13.]