Bill > HB1345

This bill establishes limitations on detached accessory dwelling units (ADUs), which are separate housing units on the same property as a main home, when they are located outside of designated urban growth areas. Counties that plan under chapter 36.70A RCW can allow these detached ADUs if they meet specific requirements, including having only one ADU per parcel, ensuring adequate water supply and sewage capacity, and adhering to size limits no larger than 1,296 square feet and not exceeding the size of an expanded attached ADU. Additionally, detached ADUs must share the same driveway as the principal unit, be located within 150 feet of it, and cannot be on lots smaller than one acre. The bill also mandates that counties implement code enforcement measures for unpermitted ADUs, including penalties and potential prohibitions on future permits, and requires them to track ADU development and incorporate it into their comprehensive land use plans to ensure housing density limits are not exceeded. Finally, it sets population growth targets for ADUs, with rural counties allowed to allocate up to 10% and non-rural counties up to 7% of their rural population target to detached ADUs.