THINKING: housing

A New Year, New ADU Laws (and Accessory Gingerbread Units too!)

As 2019 draws to a close, OpenScope studio has approximately 15 Accessory Dwelling Unit (ADU) projects under construction in San Francisco, ranging from one to five units each. We have dozens more in the pipeline, with some being as large as 12-15 units as apartment building owners decide to convert underutilized space into new housing.

garage conversion into studio ADU
This used to be a garage!

We’re looking forward to 2020 as a series of new state laws take effect that will make it easier to build ADUs across California (CARLA has summarized them here). While there are still some areas of the law that are open to interpretation, here’s what we know:

  • Only 4′ setbacks at side and rear property lines will be required, contrary to current law in many jurisdictions (like San Francisco) that requires huge rear yards.
  • A prohibition on minimum lot sizes for ADUs
  • 16′ tall ADUs will be allowed statewide, some jurisdictions may allow taller heights under local regulations.
  • Two ADUs will be allowed on single family residential lots- one “Junior” ADU and one regular ADU.
  • Multifamily parcels will be open to ADU development as well, with up to an additional 25% of the existing unit count in multifamily buildings (subject to Building Codes) being allowed and up to two ADUs in a freestanding structure.
  • A prohibition on requiring replacement parking when a garage is converted to a dwelling unit.
  • Owner occupancy requirements are being rolled back and caps are being placed on impact fees.
New detached ADUs will only be required to have 4′ setbacks, delicious sugary icicles are optional

OpenScope’s staff Holiday Party turned into the Accessory Gingerbread Festival this year, where guests were invited to build their own ADUs out of gingerbread and candy on a site model built to represent one of San Francisco’s typical single family homes on a 25′ x 100′ lot. The designs were incredibly creative and reflected the wide range of new homes we hope to see all across California in the coming year.