Accessory Dwelling Unit Legislation Proposed in Washington Sets a New Standard

If it approves HB 1797, Washington will pace the rest of the nation (even California and Oregon) on reforming zoning to allow more accessory dwelling units.

1 minute read

January 31, 2019, 2:00 PM PST

By James Brasuell @CasualBrasuell


Single-Family Neighborhood

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"This morning, Washington House Representatives Mia Gregerson (D-SeaTac) and Andrew Barkis (R-Olympia) introduced the most progressive accessory dwelling unit (ADU) bill legislators from any state have ever had the opportunity to vote on," reports Margaret Morales.

The legislation applies to all cities in Washington with 2,500 residents or more. Here, Morales provides a list of the regulatory changes included in the far-reaching bill, as described exactly in the article:

  • Permit two ADUs per lot wherever there is a single-family home, duplex, triplex, or townhome
  • Eliminate off-street parking, owner-occupancy, and minimum lot size requirements
  • Cap impact fees at 50 percent of those for single-family homes
  • Set utility connection fees and capacity charges in proportion to the ADU’s burden on the utility system
  • Increase design flexibility via more generous setback, height, and size limits

For comparison's sake, Morales says this law, if passed, would be more comprehensive and impactful than laws approved in the state of Oregon and California in recent years.

ADU policy in Washington is already fickle. Locals pushed back on ADU reform approved by the state in 1993, but Washington cities that have recently allowed more permissive ADU regulations have seen a resulting spike in permits, according to Morales.

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