The bill adds new sections to chapters 35.21 and 35A.21 RCW and requires cities and code cities to adopt or amend ordinances and incorporate those requirements into development, zoning, preservation ordinances, and other official controls for residential or mixed‑use zoned properties. It creates a new legal restriction on local historic landmark designations by prohibiting a city or code city from designating a property as a historic landmark if the property is less than 40 years old, and by prohibiting any designation that restricts use, alteration, or demolition without the property owner’s written consent; a designation made without written consent is void until consent is obtained. The age and owner‑consent limits do not apply to properties located within a historic district established through a local preservation ordinance. The bill imposes a one‑year deadline from the effective date of the new sections for cities and code cities to adopt the required ordinances; if they do not adopt them within that timeline, the specified statewide requirements automatically take effect in that jurisdiction and supersede conflicting local regulations. The bill also reenacts and amends RCW 43.21C.495 to list certain ordinance adoptions, development regulations, and other nonproject actions by cities (and in some cases counties) that are not subject to administrative or judicial appeals under that chapter, with stated exceptions including actions with a probable significant adverse impact on fish habitat and a specified exception in RCW 36.70A.600(1)(f). The text provided does not include definitions for key terms such as "city," "code city," "historic landmark," "historic district," or how the 40‑year age is measured, does not state the effective date of the new sections, and does not describe procedures for obtaining or documenting the required written owner consent or for establishing a historic district. Further consultation of the full bill and the referenced statutes would be needed to resolve those gaps.

If enacted, cities and code cities will have to change local zoning and preservation rules within a year so they cannot designate individual residential or mixed-use properties as historic landmarks if the building is less than 40 years old, and they cannot impose landmark restrictions on use, alteration, or demolition without the property owner’s written consent. Property owners of qualifying buildings will likely gain more control and face fewer surprise restrictions, while city planning departments will need to spend staff time drafting and adopting new ordinances or face state-imposed rules that override local regulations. The changes also limit the ability to appeal certain ordinance adoptions or other nonproject actions under the referenced review chapter, which could reduce legal challenges to those local regulatory updates but leaves exceptions (for example, significant fish habitat impacts). Important details are missing from the extracted text—such as the section’s effective date, how the 40-year age is measured, and how owner consent must be documented—so cities and owners may face uncertainty until those implementation details are clarified.