San Leandro, CA

Accesory Dwelling Unit (ADU) City Regulations


RS | RO | RS-40 | RS-VP | RD | RM

Lot Size:

No minimum, but must have room on lot to add an ADU outside of the required setbacks.

Maximum ADU Floor Area:

Attached – no more than 50% of the main dwelling.

Detached on lots 7,500 sq. ft. or less – 10% of the lot area or 50% of the floor area of the main dwelling, whichever is less, up to 750 sq. ft.

       on lots 7,500-9,999 sq. ft. – the lesser of 750 sq. ft. max or 50% of floor area

       on lots 10,000-19,999 sq. ft. – the lesser of 900 sq. ft. max or 50% of floor area

       on lots 20,000-39,999 sq. ft. – the lesser of 1,050 sq. ft. max or 50% of floor area

       on lots 40,000 sq. ft. or more – the lesser of 1,200 sq. ft. max or 50% of floor area

Number of Bedrooms:

No min/max.


No min/max.


All ADUs shall include permanent provisions for living, sleeping, eating, cooking and sanitation.


One space is required for an ADU, with one additional space being required for every additional bedroom.
Parking may be located in a garage or carport, on an extended paved driveway, or in tandem on an existing driveway. Parking waivers as mandated by California Government Code Sec. 65852.2 apply.


ADUs shall comply with all setback requirements established by the Zoning Code. No setbacks are required for an existing garage converted into an ADU, provided the construction meets all applicable building and fire codes.


Detached ADUs in RS/RD/RM/RO districts must comply with the underlying zoning requirements for accessory structures. If RS-VP, 18’ and one-story maximum.


New construction ADUs built above the first-floor roofline are prohibited except where existing habitable space above the first-floor roofline is converted into an ADU. Attached ADUs are not permitted in required yard space. ADUs located on or adjacent to real property listed in the California Register of Historic Places are prohibited.

Rear Yard Coverage:

Must comply with yard coverage requirements of underlying zoning district.


ADUs must appear subordinate to the existing dwelling and be consistent with the General Plan. Materials, design, forms, colors, and finishes must be compatible with the existing dwelling.


Exterior entry must be clearly made to appear secondary to the entry of the existing dwelling. Second story ADUs shall not be accessed by an exterior stairway visible from the public right-of-way.

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