Thorough, Impactful ADU Reform Proposed in Washington State

A model of accessory dwelling unit reform will be under consideration this year in the Washington State Legislature.

1 minute read

January 16, 2020, 10:00 AM PST

By James Brasuell @CasualBrasuell


Granny Flat

Nicolás Boullosa / Flickr

"Washington state representatives Mia Gregerson (D-SeaTac) and Andrew Barkis (R-Olympia) introduced a new bill in Olympia yesterday evening (HB 2570) that would lift barriers to backyard cottages and mother-in-law apartments across the state," reports Margaret Morales.

This isn't the first time Morales has reported news of the state of Washington's efforts to significantly loosen residential land use regulations throughout the state. In January 2019, the state was considering a law (HB 1797) that Morales described as the most ambitious of any in the United States.

The new bill "would dismantle five top barriers homeowners face to building ADUs on their property." Morales describes those reforms as follows:

  • 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

Morales maintains that, if approved, HB 2570 would go beyond the reforms that have legalized accessory dwelling units in the states of California and Oregon in recent years.

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