5 county-level rules, plus city-specific rules for 10 cities in San Diego County, California.
Verified from official government sources
San Diego County allows Accessory Dwelling Units (ADUs) on residential properties in unincorporated areas per state law and the County ADU Handbook. Detached ADUs up to 1,200 sq ft. Must maintain 4-foot side/rear setbacks. ADUs up to 800 sq ft are exempt from lot coverage limits.
Small accessory structures (sheds) under 120 sq ft and one story do not require a building permit in unincorporated San Diego County per County Code Section 91.1.105.2. Larger structures need permits. All sheds must comply with zoning setback requirements.
Garage conversions to ADUs or habitable space in unincorporated San Diego County require building permits. California law allows garage conversions to ADUs without replacement parking. The conversion must meet building code requirements for habitable space including egress, ventilation, and plumbing.
Carports in unincorporated San Diego County are considered accessory structures and must comply with zoning setback requirements. Carports over 120 sq ft require building permits. In wildfire zones, carport construction must meet fire-resistant material standards.
Tiny homes in unincorporated San Diego County are regulated differently based on type. Tiny homes on foundations are treated as ADUs (up to 1,200 sq ft detached). Tiny homes on wheels are treated as RVs and cannot serve as permanent dwellings. Building permits required for foundation-based tiny homes.
10 cities in San Diego County have their own accessory structures rules. Each link goes to that city's dedicated page with code citations.
9 verified rules • ADU Impact Fees, ADU Owner Occupancy
9 verified rules • ADU Impact Fees, ADU Owner Occupancy
5 verified rules • ADU Rules, Carport Rules
9 verified rules • ADU Impact Fees, ADU Owner Occupancy
9 verified rules • ADU Impact Fees, ADU Owner Occupancy
9 verified rules • ADU Impact Fees, ADU Owner Occupancy
5 verified rules • ADU Rules, Carport Rules
5 verified rules • ADU Rules, Carport Rules
4 verified rules • ADU Rules, Carport Rules
1 verified rule • ADU Rules
See every category we cover for San Diego County — parking, noise, fences, fires, animals, pools, and more.
San Diego County Ordinance Hub →