R401.1 Scope. This chapter applies to residential buildings. Group R-2 occupancy areas with dwelling units accessed from enclosed interior corridors or other enclosed interior spaces must comply with the Washington State Energy Code (WSEC), Commercial Provisions. Other Group R-2 occupancy areas are permitted to comply with the WSEC, Commercial Provisions, in lieu of the WSEC, Residential Provisions.
EXCEPTION: | Water heaters that each serve only an individual Group R-2 dwelling unit in a building three stories or less above grade plane areev |
R401.2 Compliance. Projects shall comply with one of the following:
1. Sections R401 through R404. In addition, dwelling units and sleeping units in a residential building shall comply with Section R406.R401.3 Certificate. A permanent certificate shall be completed by the builder or other approved party and posted on a wall in the space where the furnace is located, a utility room, or an approved location inside the building. When located on an electrical panel, the certificate shall not cover or obstruct the visibility of the circuit directory label, service disconnect label, or other required labels. The certificate shall indicate the following:
1. The predominant R-values of insulation installed in or on ceiling/roof, walls, foundation (slab, below-grade wall, and/or floor) and ducts outside conditioned spaces.2.U-factors for fenestration and the solar heat gain coefficient (SHGC) of fenestration. Where there is more than one value for each component, the certificate shall indicate the area weighted average value.3. The results from any required duct system and building envelope air leakage testing done on the building.4. The results from the whole-house mechanical ventilation system flow rate test.5. The types, sizes, and efficiencies of heating, cooling, whole-house mechanical ventilation, and service water heating appliances. Where a gas-fired unvented room heater, electric furnace, or baseboard electric heater is installed in the residence, the certificate shall list "gas-fired unvented room heater," "electric furnace" or "baseboard electric heater," as appropriate. An efficiency shall not be listed for gas-fired unvented room heaters, electric furnaces or electric baseboard heaters.6. Where on-site photovoltaic panel systems have been installed, the array capacity, inverter efficiency, panel tilt, orientation and estimated annual electrical generation shall be noted on the certificate.7. The code edition under which the structure was permitted, and the compliance path used. The code official may require that documentation for any required test results include an electronic record of the time, date, and location of the test. A date-stamped smart phone photo or air leakage testing software may be used to satisfy this requirement.
Wash. Admin. Code § 51-11R-40100
Amended by WSR 16-02-127, Filed 1/6/2016, effective 7/1/2016Amended by WSR 20-01-047, Filed 12/9/2019, effective 7/1/2020Amended by WSR 23-02-060, Filed 1/3/2023, effective 7/1/2023Statutory Authority: RCW 19.27A.020, 19.27A.045 and chapters 19.27 and 34.05 RCW. 13-04-055, § 51-11R-40100, filed 2/1/13, effective 7/1/13.