(1) The state building code council in the department of enterprise services shall adopt rules to be known as the Washington state energy code as part of the state building code.

(2) The council shall follow the legislature's standards set forth in this section to adopt rules to be known as the Washington state energy code. The Washington state energy code shall be designed to:

(a) Construct increasingly energy efficient homes and buildings by the year 2031;

(b) Require new buildings to meet a certain level of energy efficiency, but allow flexibility in building design, construction, and heating equipment efficiencies within that framework; and

(c) Allow space heating equipment efficiency to offset or substitute for building envelope thermal performance.

(3) The Washington state energy code may not in any way prohibit, penalize, or discourage the use of gas for any form of heating, or for uses related to any appliance or equipment, in any building.

(4) The Washington state energy code shall take into account regional climatic conditions. One climate zone includes: Adams, Asotin, Benton, Chelan, Columbia, Douglas, Ferry, Franklin, Garfield, Grant, Kittitas, Klickitat, Lincoln, Okanogan, Pend Oreille, Skamania, Spokane, Stevens, Walla Walla, Whitman, and Yakima counties. The other climate zone includes all other counties not listed in this subsection (4). The assignment of a county to a climate zone may not be changed by adoption of a model code or rule. Nothing in this section prohibits the council from adopting the same rules or standards for each climate zone.

(5) The Washington state energy code for residential buildings shall be the 2006 edition of the Washington state energy code, or as amended by rule by the council.

(6) The minimum state energy code for new nonresidential buildings shall be the Washington state energy code, 2006 edition, or as amended by the council by rule.

(7)(a) Except as provided in (b) of this subsection, the Washington state energy code for residential structures shall preempt the residential energy code of each city, town, and county in the state of Washington.

(b) The state energy code for residential structures does not preempt a city, town, or county's energy code for residential structures which exceeds the requirements of the state energy code and which was adopted by the city, town, or county prior to March 1, 1990. Such cities, towns, or counties may not subsequently amend their energy code for residential structures to exceed the requirements adopted prior to March 1, 1990.

(8) The state building code council shall consult with the department of enterprise services as provided in RCW 34.05.310 prior to publication of proposed rules. The director of the department of enterprise services shall recommend to the state building code council any changes necessary to conform the proposed rules to the requirements of this section.

(9) The state building code council shall evaluate and consider adoption of the international energy conservation code in Washington state in place of the existing state energy code.

(10) The definitions in RCW 19.27A.140 apply throughout this section.

Findings—2025 c 1 (Initiative Measure No. 2066): See note following RCW 80.28.110.

Effective date—2018 c 207 ss 1-8: See note following RCW 19.27.070.

Finding—Intent—2015 c 11: See note following RCW 19.27.031.

Purpose—Effective date—2010 c 271: See notes following RCW 43.330.005.

Findings—Intent—Part headings not law—Effective date—1996 c 186: See notes following RCW 43.330.904.

Effective date—1994 c 226: "This act is necessary for the immediate preservation of the public peace, health, or safety, or support of the state government and its existing public institutions, and shall take effect immediately [April 1, 1994]." [ 1994 c 226 s 2.]

Effective dates—1990 c 2: See note following RCW 19.27.040.

Findings—Severability—1990 c 2: See notes following RCW 19.27A.015.

Severability—1985 c 144: "If any provision of this act or its application to any person or circumstance is held invalid, the remainder of the act or the application of the provision to other persons or circumstances is not affected." [ 1985 c 144 s 7.]