Legislation to Lift Local Prohibition of Middle Housing Proposed in Washington State

Washington State is the latest example of a state that wants to preempt local planning law to make it easier to add housing units to single-family residential properties all over the states.

1 minute read

January 23, 2020, 9:00 AM PST

By James Brasuell @CasualBrasuell


Missing Middle Housing

A SE Portland duplex. | Sightline Institute: Missing Middle Homes Photo Library / Flickr

Dan Bertolet reports on statewide legislation introduced yesterday in Washington by State Representative Nicole Macri (D-Seattle) that would "lift local bans on small-scale, multiple-dwelling homes known as 'middle housing,'"

As explained by Bertolet, HB 2780 would re-legalize, "triplexes on any lot, and up to sixplexes in single-detached house zones in counties and cities of 15,000 or more," as well as, "duplexes on any lot in all cities between 10,000 and 15,000."

HB 2780 joins a growing roster of bills currently under consideration in the Washington Legislature that would ease zoning restrictions and other forms of housing regulation around the state. HB 2570 would ease the construction of backyard cottages and mother-in-law apartments. HB 1923, approved in 2019, increased building capacity around the state, but through incentives rather than a mandate.

HB2780 also joins a growing roster of bills in other states that would preempt local law to allow for more density in single-family zones around the state. Oregon already passed a law, but California, Maryland, Virginia, and Nebraska are considering similar reforms of the traditional single-family zoning designation to allow more space for homes of different sizes in residential neighborhoods.

Tuesday, January 21, 2020 in Sightline Institute

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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