+1(408) 380-4234
San Jose
Mon.-Fri. 09AM-06PM

San Carlos CA ADU Guidelines

Accessory Dwelling Unit (ADU) City Regulations


Any Single-family residential zoning district.

*ADUs are permitted only on lots with access from a roadway that meets California Fire Code Section 902.2.2.1

Lot Size:

No minimum/maximum as long as lot abides by zone standards.

ADU Floor Area:

Attached: may be 30% of the home's square-footage in area up to 1,200 sq.ft. maximum.

Detached: limited to 640 sq.ft. maximum.

Number of Bedrooms:

No minimum/maximum (provided there are separate, independent living quarters for one household).


No minimum/maximum.


Requires separate kitchen facilities (permanent range, counters, refrigerator, and sink) and bathroom.


One on-site parking space must be provided for ADU in addition to parking required for primary residence. Tandem parking allowed.


Attached: must adhere to underlying zoning district's setbacks.

Detached: must maintain a min. of 5’ from side and rear lot lines and must also conform to setbacks established in underlying zoning district.


Cannot exceed 15' unless located over a garage, wherein max. height allowed is 28'.


Attached: may be located within existing primary residence.

Detached: may be located on rear half of lot and may be second floor of garage provided secondary unit maintains underlying zoning districts established setbacks. Additionally, there can be no other ADU within 400' measured from the nearest edge of lot line of each respective or proposed second dwelling unit (may be waived by Director upon review).

Rear Yard Coverage:

Must follow requirements established by zoning district in which lot is located and any other applicable City codes.


Architectural design, exterior materials and colors, roof pitch and style, type of windows, and trim details of ADU shall be substantially the same as and visually compatible with primary dwelling.


Doors and windows for detached ADUs must be located at least 10' from an interior side or rear lot line. Attached ADUs do not have such a requirement.

For more ADU Information:

WordPress Theme built by Shufflehound.

Copyright © 2019-2020 California Modulars, LLC. All rights reserved | Inc.

California Modulars serves Silicon Valley and the entire Northern California and the surrounding areas of Campbell, Cupertino, Los Altos, Los Gatos, Menlo Park, Palo Alto, San Jose, Santa Clara, Saratoga, Oakland, San Francisco, Sacramento, Daly City, Berkeley, Morgan Hill, Dublin, Union City, Hayward, Milpitas, Fremont, Morgan Hill, Santa Cruz, Redwood City, San Bruno, San Mateo, Santa Rosa, Sonoma  County & surrounding areas of Bay Area, Northern California.

Order a Feasibility Study

Do NOT follow this link or you will be banned from the site!