This bill introduces new regulations regarding exterior cladding materials for cities, code cities, and counties in Washington State. It prohibits these entities from requiring or excluding exterior cladding materials that comply with the state building code, defining "exterior cladding" as a nonload-bearing material attached to a building's exterior. However, there are exceptions to this prohibition, including homeowners' associations, historic districts, and areas subject to specific building codes, such as those requiring fire-resistant siding materials for wildfire protection.

The bill adds new sections to chapters 35.21, 35A.21, and 36.01 of the Revised Code of Washington (RCW), ensuring that the limitations on regulating exterior cladding do not apply to certain designated areas and structures. These exceptions include local historic districts, national historic landmarks, and specific architectural themes, such as old world Bavarian styles. The legislation aims to standardize the treatment of exterior cladding materials while allowing for necessary local regulations in specific contexts.