The challenge
California had a deep housing shortage, and local rules blocked even small new homes.
The case
From 2016, California passed a series of laws limiting how cities could block accessory dwelling units, the small backyard cottages, garage conversions and in-law units built on existing home lots. The laws cut approval times, removed many parking and fee requirements, and made approval largely automatic. ADU permits in the state's largest metro areas increased from 654 in 2016 to 3,126 in 2017. In Los Angeles they went from just 80 permits in 2016 to 1,980 in 2017. Statewide, permits rose from 5,911 in 2018 to 15,571 in 2019, and completions more than tripled.
Why it worked
Removing local veto points unlocked supply homeowners were ready to build. ADUs add homes gently in existing neighborhoods, though they can't replace large-scale apartment construction.
Sources
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