Clyde Hill: Middle Housing and ADU Regulations Update

In response to a series of 2023 legislative mandates from Washington State, the City of Clyde Hill has successfully updated its local development regulations to address the requirements for middle housing, accessory dwelling units (ADUs), and unit lot subdivisions. This comprehensive effort, completed in June 2025, was driven by three key bills: HB 1110, which requires cities to allow more than one housing unit per lot in single-family zones; HB 1337, which mandates the allowance of at least two ADUs per lot; and HB 5258, which requires cities to permit the subdivision of lots to allow for separate ownership of these units. The city's primary goal throughout this process was to meet the state-level requirements while carefully preserving the existing character and aesthetic of its neighborhoods, a preference that was strongly expressed by residents during the city's 2024 Comprehensive Plan update.