All Accessory Dwelling Units (ADUs) require a Design Review Exemption (DRX) Permit from the Planning/Zoning Bureau, along with Building Permits.
Here are the categories of Single-Family ADUs under California state law:
- JUNIOR ADU (JADU): Involves conversion of space within the building envelope of an existing or proposed One-Family Residential Facility, resulting in a living unit of not more than 500 sq. ft., requiring owner-occupancy in the JADU or primary dwelling unit.
- CATEGORY ONE ADU: Involves either conversion of space within an existing One-Family Residential Facility, or conversion or rebuild of an existing accessory structure; includes no expansion of the existing building envelope other than up to 150 sq. ft. for purposes of accommodating ADU access and egress only.
- CATEGORY TWO ADU: Involves construction of a new detached or attached accessory structure, including an exterior addition to an existing or proposed One-Family Residential Facility to accommodate the ADU.
Please note that a Category 1 OR a Category 2 ADU may be combined on the lot with one JADU. However, a lot may NOT contain both a Category 1 ADU and a Category 2 ADU. If a lot contains two ADUs, one must be a JADU.
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See below for step-by-step requirements to apply for your ADU permits or review our Guidebook to Single-Family ADUs.