Santa Clara County, California: ADU Regulations

City or County:
Santa Clara County, California

Zoning:

Allowable Urban Districts: R1/R1E/RHS/R1S/R3S/A1

Allowable Rural Zones: A/AR/HS/RR

Types of ADUs:

Attached, Detached and Junior ADU

Stories:

Urban Districts: Single-story

Rural Districts: up to two-stories depending on lot size.

Lot Size:

Urban Districts:

On lots less than 10,000 sq. ft. only attached ADUs allowed. On lots larger than 10,000 sq. ft. either attached or detached permitted.

Rural Districts:

On lots .5 to less than one acre, only attached ADUs allowed. The min. lot size for detached is one acre.

Maximum ADU Floor Area:

Urban Attached:

Lots <20,000 sq.ft., 800 sq.ft. max;

Lots >20,000 sq.ft., 1,000 sq.ft. max

Urban Detached: 1,000 sq.ft. max

Rural Attached:

Lots <1 acre, 800 sq.ft. max

Lots 1-2.5 acres, 1,000 sq.ft.

Lots >2.5 acres, 1,200 sq.ft.

Rural Detached:

Lots <1 acre, 800 sq.ft. max.

Lots 1-2.5 acres, 1,000 sq.ft.

Lots >2.5 acres, 1,200 sq.ft.

Lot Coverage:

Must adhere to coverage limits of underlying zoning district.

Bedroom:

2 bedrooms maximum.

Storage:

No min/max

Kitchen:

Require separate kitchen facilities.

Bath:

ADUs require separate bathroom facilities.

Junior ADUs may include separate bathroom or may share bathroom with existing structure.

Note: Drainage and sewer connections should be assessed on a project by project basis.

Parking:

One off-street parking space per unit required for secondary dwelling.

One additional space required for a secondary dwelling with more than one bedroom.

For applicable parking exemptions, see Section 4.10.340(FX3).

Setbacks:

Must follow guidelines of underlying zoning district.

Setback of no more than five feet from side and rear property lines required for above existing garage units.

Note: Fire Department regulations should be assessed on a project by project basis.

Height:

May not exceed 21'

Location:

Urban ADUs may be no nearer than 6' to primary dwelling.

Rear Yard Coverage:

Must follow requirements established by zoning district in which lot is located.

Design:

Unless noted on Priority Lists No. 1 and 2, design standards are advisory. Certain features, materials or forms may be required by means of design review or ASA approval.

Note: Historic Neighborhoods or Districts should be assessed on a project by project basis.

Entryways:

N/A