(1) For residential construction, the industrial statistician shall establish the prevailing rate of wage by conducting wage and hour surveys. If the industrial statistician determines that information received from a survey is insufficient to determine the prevailing rate of wage for a trade under this subsection, the industrial statistician shall employ other appropriate methods to establish the prevailing rate of wage.
(a) The industrial statistician shall conduct the initial surveys required by this subsection (1) as soon as feasible after April 17, 2019. These surveys shall cover fiscal year 2018.
(b) The industrial statistician shall conduct a wage and hour survey following the initial survey or otherwise reestablish a prevailing rate of wage for each trade covered by this section at least every five years, and after the initial survey may stagger the surveys for workload purposes.
(2)(a) Until the industrial statistician has established a prevailing wage rate under subsection (1)(a) of this section and except as provided in (b) of this subsection, the industrial statistician shall establish the wage rate by:
(i) Identifying the residential prevailing wage rate in effect on August 30, 2018, for that trade (rate A);
(ii) Determining the year most recent to 2018, but not earlier than 2007, in which the wage rate for that trade was adjusted (year A);
(iii) Determining the percentage change in the annual average hourly wages reported for construction workers in Washington state, as calculated by the United States bureau of labor statistics' state and area employment, hours, and earnings estimates, from year A to 2019;
(iv) Adding the percentage change from (a)(iii) of this subsection to one hundred percent (percentage A); and
(v) Multiplying rate A by percentage A.
(b) If the residential construction wage rate in effect for a trade on August 31, 2018, is the same as the wage rate in effect on August 30, 2018, the industrial statistician must adopt the wage rate in effect for the trade on August 31, 2018, until a wage rate is established under subsection (1)(a) of this section.
(3) For purposes of this section:
(a) "Residential construction" means construction, alteration, repair, improvement, or maintenance of single-family dwellings, duplexes, apartments, condominiums, and other residential structures not to exceed four stories in height, including the basement, in the following categories:
(i) Affordable housing, including permanent supportive housing and transitional housing, which may include common spaces, community rooms, recreational spaces, a management office, or offices for the purposes of service delivery;
(ii) Weatherization and home rehabilitation programs for low-income households; and
(iii) Homeless shelters and domestic violence shelters.
(b) "Residential construction" does not include the utilities construction, such as water and sewer lines, or work on streets, or work on other structures unrelated to the housing.