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 Multi-Family ADUs* under California state law:
- CATEGORY ONE ADU: Conversion of existing non-habitable space located within portions of an existing Two-Family or Multi-Family Residential Facilities, such as storage rooms, boiler rooms, passageways, attics, basements or garages.
- CATEGORY TWO ADU: Construction of new detached structure(s) or conversion or rebuilt of existing detached structure(s) on lots with an existing Two-Family or Multi-Family Residential Facility. Conversion or rebuilt of existing detached accessory structure(s) involve no expansion of the existing building envelope(s).
- CATEGORY THREE ADU: Construction of a new or conversion of existing accessory structure attached to a primary Multifamily Residential Facility for the purpose of creating only one ADU on the lot. This type of ADU precludes creation of any other ADU types on the lot.
* Change of Occupancy regulations for the California Existing Building Code (CEBC) may apply when adding ADUs.
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See below for step-by-step requirements to apply for your ADU permits.