The bill aims to facilitate the creation of additional housing units within existing buildings in Washington State by amending various sections of the Revised Code of Washington (RCW). It mandates that code cities and other municipalities adopt or amend their development and zoning regulations to allow for increased housing density—up to 50% more than currently permitted—within existing building envelopes located in zones that allow multifamily housing. The bill prohibits cities from imposing certain restrictions, such as parking requirements for new units, additional permitting beyond standard residential requirements, and design standards that exceed those generally applicable to residential development. It also clarifies that unchanged portions of existing buildings do not need to meet current energy codes solely due to the addition of new units, although new units must comply with these codes.

Additionally, the bill requires the state building code council to amend the current energy code by January 1, 2024, to reflect these changes. It also categorically exempts the adoption or amendment of relevant ordinances and regulations from certain environmental review requirements, streamlining the process for municipalities to comply with the new housing regulations. Overall, the legislation aims to promote housing development while maintaining necessary health and safety standards.

Statutes affected:
Bill as Passed Legislature: 43.21C.450
Session Law: 43.21C.450