The bill aims to enhance affordable and sustainable building practices in Washington by amending existing regulations and introducing new provisions. It requires cities and counties planning under RCW 36.70A.040 to allow adjustments in building codes, such as permitting retrofits of existing buildings for residential housing to exceed maximum roof heights and setbacks for insulation purposes. Additionally, it mandates similar allowances for new constructions or retrofits that meet passive house requirements. The bill also restricts cities from imposing certain limitations on housing density, parking requirements, or design standards for existing residential buildings, with exceptions only for health and safety standards.

Moreover, the legislation introduces regulations regarding the size of affordable housing units for low-income and very low-income households, establishing maximum size limits for various unit types. It specifies that if the average size of units in a project is smaller than these limits, affordable units must match the size of market-rate units. The bill also requires cities and counties to adopt or amend their development regulations to align with these new requirements within six months of their next comprehensive plan update. Overall, the bill seeks to streamline building regulations to facilitate the development of affordable housing while promoting sustainability.

Statutes affected:
Original Bill: 35.21.990, 35A.21.440, 36.70A.620, 19.27.042
Substitute Bill: 35.21.990, 35A.21.440, 36.70A.620, 70.87.030
Second Substitute: 35.21.990, 35A.21.440, 36.70A.620
Bill as Passed Legislature: 35.21.990, 35A.21.440, 36.70A.620
Session Law: 35.21.990, 35A.21.440, 36.70A.620