This bill aims to address the growing issue of housing affordability by establishing a new category of building codes specifically for "kit homes." Kit homes are defined as residential structures that are 800 square feet or smaller, made up of prefabricated walls, floors, and roofs that are assembled on-site. The legislation includes amendments to existing definitions in RCW 19.27.015, such as the insertion of the definition for "kit homes," and updates to the numbering of subsequent definitions.

Additionally, the bill mandates that the state building code council must undertake rule-making for the state building codes applicable to kit homes by December 31, 2025, and allows for updates to these codes as necessary. This initiative is part of a broader legislative effort to make housing more accessible for homebuyers of modest means, reflecting the legislature's recognition of the challenges faced by this demographic in the current housing market.