Petaluma, CA Building Setbacks & Zoning: Setback Rules (2026)

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.