Sonoma County, CA Building Setbacks & Zoning: Setback Rules (2026)
Key Facts
- R1 front yard
- Min. 20 ft; no structure within 45 ft of road centerline (Sec. 26-20-030(f))
- R1 side yard
- Min. 5 ft (equals front yard where it abuts a street)
- R1 rear yard
- Min. 20 ft
- Projections
- Eaves/bay windows 2 ft; uncovered porches 6 ft front/rear, 3 ft side
- Varies by zone
- AR, RR and resource districts have different/larger setbacks
- Ag buffer
- Parcels adjoining AR/ag land subject to buffer (Sec. 26-88-040)
Summary
Building setbacks in unincorporated Sonoma County are set by each zoning district in Chapter 26. In the R1 Low Density Residential district, the front yard must be at least 20 feet (and no structure closer than 45 feet to a road centerline), side yards at least 5 feet, and rear yards at least 20 feet. Other districts have different yards.
Sec. 26-20-030. - Permitted residential density and development criteria.
(f) Yard Requirements.
(1) Front Yard. Not less than twenty feet (20); provided, however, that no structure shall be located closer than forty-five feet (45) to the centerline of any public road, street or highway.
(2) Side Yard. Not less than five feet (5) except where the side yard abuts a street in which case such yard shall be the same as the front yard.
(3) Rear Yard. Not less than twenty feet (20).
Full Breakdown
Sonoma County's Zoning Code (Chapter 26) sets minimum yard (setback) requirements separately for each zoning district, so the exact numbers depend on your parcel's zone. For the R1 Low Density Residential district, Section 26-20-030(f) requires a front yard of not less than twenty feet (20'), provided that no structure may be located closer than forty-five feet (45') to the centerline of any public road, street or highway; side yards of not less than five feet (5'), except where a side yard abuts a street, in which case it must equal the front yard; and a rear yard of not less than twenty feet (20').
Garages and carports with openings facing the street must be at least 20 feet from the exterior property line, though this can be reduced to as little as 10 feet where most of the block is already improved. Limited architectural projections are allowed: cornices, eaves, bay windows and similar features may extend 2 feet into a required yard, and uncovered porches may extend 6 feet into a front or rear yard and 3 feet into a side yard. Accessory buildings may be placed in required yards on the rear half of the lot subject to limits.
Agricultural, rural-residential and resource districts have their own (often larger) setbacks, and parcels adjoining AR or agricultural land are subject to additional buffer requirements. Always confirm your zoning district and any recorded setback lines with Permit Sonoma.
Violations & Fines
Building within a required yard, too close to a road centerline, or in violation of recorded setback lines can result in a code-enforcement notice, denial or revocation of permits, fines, and an order to remove or relocate the structure. A variance is required to legally reduce a required setback.
Frequently Asked Questions
What are the setbacks for a house in unincorporated Sonoma County?
Can eaves or a porch extend into the setback?
Sources & Official References
Other rules in Sonoma County
California rules heatmap·Compare Sonoma County to another location·View the California building setbacks & zoning overview
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