1. (1) The model middle housing ordinances published by the department in accordance with RCW 36.70A.636(2) shall:

   1. (a) Supersede, preempt, and invalidate local development regulations in any city subject to RCW 36.70A.635 that has not passed ordinances, regulations, or other official controls within the time frames provided under RCW 36.70A.635(11).
   2. (b) Remain in effect until the city takes all actions necessary to implement RCW 36.70A.635.

2. (2) Subject to a process provided for in WAC 365-199-060, cities implementing the requirements of RCW 36.70A.635 may seek approval of alternative local actions identified in RCW 36.70A.637 (3)(b) and (c), subject to the approval process in WAC 365-199-060.

   1. (a) The department may approve actions for cities that have, by January 1, 2023, adopted a comprehensive plan that is substantially similar to the requirements of RCW 36.70A.635 and have adopted, or within one year of July 23, 2023, adopts permanent development regulations substantially similar to the requirements of RCW 36.70A.635. In determining whether a city's adopted comprehensive plan and permanent development regulations are substantially similar, the department must find as substantially similar plans and regulations that:

      1. (i) Result in an overall increase in housing units allowed in single-family zones that is at least 75 percent of the increase in housing units allowed in single-family zones if the specific provisions of RCW 36.70A.635 were implemented;
      2. (ii) Allow for middle housing throughout the city, rather than just in targeted locations; and
      3. (iii) Allow for additional density near major transit stops, and for projects that incorporate dedicated affordable housing.

   2. (b) The department may approve actions for cities that have, by January 1, 2023, adopted a comprehensive plan or development regulations that have significantly reduced or eliminated residentially zoned areas that are predominantly single family. The department must find that a city's actions are substantially similar to the requirements of RCW 36.70A.635 if they have adopted, or within one year of July 23, 2023, adopt permanent development regulations that:

      1. (i) Result in an overall increase in housing units allowed in single-family zones that is at least 75 percent of the increase in housing units allowed in single-family zones if the specific provisions of RCW 36.70A.635 were implemented;
      2. (ii) Allow for middle housing throughout the city, rather than just in targeted locations; and
      3. (iii) Allow for additional density near major transit stops, and for projects that incorporate dedicated affordable housing.
3. (3) (a) The department may determine that a comprehensive plan and development regulations that do not meet the criteria in RCW 36.70A.636 (3)(b) or (c) are otherwise substantially similar to the requirements of RCW 36.70A.635 if the city can clearly demonstrate that the regulations adopted will allow for a greater increase in middle housing production within single family zones than would be allowed through implementation of RCW 36.70A.635.
4. (b) In making this determination, the city must provide supporting documentation and calculations that compare middle housing units allowed within single-family zones under the alternative action to housing units allowed were the city to adopt applicable provisions of RCW 36.70A.635.
5. (c) In preparing the documentation and calculations, consideration should be given to housing element technical guidance documents prepared by the department for conducting housing element land capacity analysis.
6. (4) Any local actions approved by the department pursuant to RCW 36.70A.636 (b) and (c) to implement the requirements under RCW 36.70A.635 are exempt from appeals under this chapter and chapter 43.21C RCW.
7. (5) The department's final decision to approve or reject actions by cities implementing RCW 36.70A.635 may be appealed to the growth management hearings board by filing a petition as provided in RCW 36.70A.290.

[Statutory Authority: RCW 36.70A.050 and 36.70A.190. WSR 25-17-058, s 365-196-900, filed 8/15/25, effective 9/15/25.]