Section R405.2—Performance based compliance.
R405.2 Performance based compliance. Compliance based on total building performance requires that a proposed design meet all of the following:
1. The requirements of the sections indicated within Table R405.2.
2. For structures less than 1,500 square feet of conditioned floor area, the annual site energy consumption shall be less than or equal to 64 percent of the annual site energy consumption of the standard reference design.
3. For structures 1,500 to 5,000 square feet of conditioned floor area, the annual site energy consumption shall be no more than 47 percent of the standard reference design.
4. For structures over 5,000 square feet of conditioned floor area, the annual site energy consumption shall be no more than 41 percent of the standard reference design.
5. For structures serving Group R-2 occupancies, the annual site energy consumption shall be less than or equal to 61 percent of the annual site energy consumption of the standard reference design. See Section R401.1 and residential building in Section R202 for Group R-2 scope.
Energy use derived from simulation analysis shall be expressed in Btu per square foot of conditioned floor area per year.
TABLE R405.2
MANDATORY COMPLIANCE MEASURES FOR TOTAL BUILDING PERFORMANCE
Sectiona | Title | Comments |
General |
R401.3 | Certificate | |
Envelope |
R402.1.1 | Vapor retarder | |
R402.2.3 | Eave baffle | |
R402.2.4.1 | Access hatches and doors | |
R402.4 | Air leakage | |
R402.5 | Maximum fenestration U-factor | |
Systems |
R403.1 | Controls | |
R403.3 | Ducts | Except for R403.3.2 and R403.3.3 |
R403.4 | Mechanical system piping insulation | |
R403.5.1 | Heated water circulation and temperature maintenance system | |
R403.5.3 | Drain water heat recovery units | |
R403.6 | Mechanical ventilation | |
R403.7 | Equipment sizing and efficiency rating | |
R403.8 | Systems serving multiple dwelling units | |
R403.9 | Snow melt system controls | |
R403.10 | Energy consumption of pools and spas | |
R403.11 | Portable spas | |
R403.12 | Residential pools and permanent residential spas | |
Electrical Power and Lighting |
R404.1 | Lighting equipment | |
R404.2 | Interior lighting controls | |
a | Reference to a code section includes all the relative subsections except as indicated in the table. |
[Statutory Authority: RCW
19.27A.020,
19.27A.045,
19.27A.160, and chapter
19.27A RCW. WSR 24-03-084, § 51-11R-40520, filed 1/16/24, effective 3/15/24; WSR 23-02-060, 23-12-102, and 23-20-022, § 51-11R-40520, filed 1/3/23, 6/7/23, and 9/25/23, effective 3/15/24. Statutory Authority: RCW
19.27A.045 and chapter
19.27A RCW. WSR 22-10-094, § 51-11R-40520, filed 5/3/22, effective 6/3/22. Statutory Authority: RCW
19.27A.020,
19.27A.045,
19.27A.160 and chapter
19.27 RCW. WSR 20-01-047, § 51-11R-40520, filed 12/9/19, effective 7/1/20. Statutory Authority: RCW
19.27A.020,
19.27A.045 and chapters
19.27 and
34.05 RCW. WSR 13-04-055, § 51-11R-40520, filed 2/1/13, effective 7/1/13.]
