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Accessory Dwelling Units (ADUs) / Secondary Units

Accessory Dwelling Units (ADUs) — also known as Secondary Units — are attached or detached accessory dwellings that provide independent living for one or more people, including permanent facilities for living, sleeping, eating, cooking, and sanitation. As of January 1, 2020, state and local laws surrounding ADUs have changed to allow for their construction with Single- and Multi-Family dwellings. See the "Documents" section below for new applications that conform to the latest requirements.

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To help expand housing options for Oakland residents, the City is streamlining the process for property owners to build Accessory Dwelling Units (ADUs) on their lots. As of January 1, 2020, state and local laws surrounding ADUs have changed.

Here are the new categories of ADUs under California state law:


  • CATEGORY ONE ADU: Involves construction within an existing living area or accessory structure (EXCEPT for Junior ADU - see below), or in a new detached structure built in the same location and to the same dimensions as an existing detached accessory structure; involves no expansion of the existing building envelope other than up to 150 square feet for purposes of accommodating ADU access and egress only; and side and rear setbacks are sufficient for fire safety.
  • CATEGORY TWO ADU: Involves construction of a new structure or exterior addition to an existing structure of more than 150 square feet.
  • JUNIOR ADU (JADU): JADUs are small living units contained entirely within an existing or proposed One-Family dwelling. A JADU is created by adding an efficiency kitchen* and exterior door to a legal bedroom. It may include a bathroom or may share a bathroom with the primary residence.

    * Efficiency Kitchen: An efficiency kitchen shall include all of the following: a sink, cooking facility, a food preparation counter and storage cabinets that are of a reasonable size in relation to the size of the junior accessory dwelling unit.


  • CATEGORY ONE ADU: Conversion of a non-living space located within an existing Two-Family Dwelling or Multi-Family Dwelling Facility; maximum number of ADUs is up to 25% of existing units in building or one unit, whichever is greater.
  • CATEGORY TWO ADU: Construction of new detached structure(s); up to two ADUs per lot; 16 feet height limit; 4 feet side & rear setbacks.

    * Change of Occupancy regulations for the California Existing Building Code (CEBC) may apply when adding ADUs.

Please see the Documents section for new ADU applications that conform to the latest legal requirements.

Contact Us

Map location for Accessory Dwelling Units (ADUs) / Secondary Units, located at 250 Frank H. Ogawa Plaza in Oakland, CA 94612
250 Frank H. Ogawa Plaza
2nd Floor, Permit Center
Oakland, CA 94612

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