ADU Demand Grows Across the West Coast

In communities from California to Washington, permit applications for accessory dwelling units outpace the ability of permitting and construction to keep pace.

1 minute read

July 14, 2023, 8:00 AM PDT

By Diana Ionescu @aworkoffiction


Small gray backyard cottage with glass door and bike sitting in front of it

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A report from Cottage ADU, an accessory dwelling unit (ADU) builder on the west coast, reveals that demand for ADUs is growing rapidly as states liberalize zoning restrictions on backyard homes to incentivize construction of more affordable housing in existing neighborhoods.

“In 2022, California homeowners applied for over 30,000 ADU permits – twice as many as in 2018, the year before statewide ADU reforms went into effect.” Farther up the coast, demand for ADUs in Seattle is growing faster than in any California metro area, with 2,254 applications for permits in 2022.

However, “There remains a notable gap between ADUs that start the permitting process and the number of ADUs that actually get built.” In California, only a third of permits since 2017 resulted in completed ADUs. The report attributes this to the complex processes for ADU permitting, understaffed city departments, and supply chain and labor shortages.

Legalizing ADUs is becoming a popular way for cities to move the needle on the nationwide housing crisis as backyard cottages and other additions can be sold to reluctant community groups as a reasonable increase in density that can bring homeowners extra income.

Wednesday, July 5, 2023 in Cottage ADU

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