Missing Middle Housing: Key Considerations for Seattle's Implementation of House Bill 1110

Abstract

Seattle is experiencing a housing crisis. The city needs to build a substantial amount of housing in order to adequately meet the current and future housing needs of its residents. However, supply has not kept pace with demand, resulting in a severe housing shortage and affordability challenges. One significant reason for the inadequate supply of housing is Seattle’s current zoning and development policies that favor low-density, high-cost single-family homes, while severely inhibiting affordable and middle housing types. In response, the Washington State Legislature introduced HB 1110 that allows the development of middle housing in cities across the state, including Seattle, on lots previously zoned exclusively for single-family homes. Highlighting the inadequate supply of housing and the lack of diverse housing opportunities, this thesis examines zoning and land use reforms in Minneapolis, Portland, and Los Angeles and their implications for the development of middle housing. I find that eliminating single-family zoning by itself will not facilitate the development of middle housing types; other barriers and constraints exist that hinder middle housing development. I conclude by offering key considerations for the City of Seattle as it implements the requirements set by the State under HB 1110, including adopting standards above baseline requirements, creating flexible design standards, easing financial constraints, providing technical assistance, and streamlining permitting and development processes.