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3932 Woodcreek Lane San Jose, CA 95117

(408) 490-4248

Accessory Dwelling Unit (ADU) City Regulations for

Los Altos Hills, CA

Los Altos Hills is an incorporated town in Santa Clara County, California.  If visiting the area be sure to check out the beautiful Rancho San Antonio Open Space Preserve or catch a show at Foothill College Smithwick Theatre.


Attached/Detached: R-A

Lot Size:

Attached/Detached: 1 acre

Maximum ADU Floor Area:

Attached/Detached: 1,000 sq.ft.

Number of Bedrooms:

Min. 1 bedroom.


No min/max


Require separate bathroom and kitchen facilities (permanent range, counters, refrigerator, and sink). Must have at least 1 bathroom.


At least 1 parking space must be provided in addition to 4 mandatory spaces of primary dwelling. Parking space must be 10’x20′ and to abide by setback standards of zone. Vehicular access to ADU must be by common driveway with primary dwelling.


Attached/Detached: Must comply with min. requirements of underlying zone.


Attached: must comply with requirements of underlying zoning district and maintain cohesive appearance with structure of primary dwelling.

Detached: must comply with standards of underlying zoning district (max 27′ per section 10-1.504(a)).


If separate from primary dwelling, ADU shall not be sited in visually prominent location and shall respect the visual and acoustic privacy of primary dwellings on contiguous lots. Additionally, views of prominent scenic features by primary dwellings on contiguous lots to be preserved.

Rear Yard Coverage:



Secondary dwelling to be subordinate to and architecturally consistent with primary dwelling