Before You Build in San Diego County, CA: Permit & Rule Checklist (2026)

In unincorporated San Diego County, open fences (wire, wrought iron, pipe, rails) may be up to 72 inches (6 ft). Fences in visibility areas (intersections, driveways) cannot exceed 3 feet. Solid fences in front yards limited to 42 inches. Rear and side yard fences up to 6 feet.

California Civil Code Sections 841–841.4 (Good Neighbor Fence Act) govern shared boundary fences statewide, including unincorporated San Diego County. Adjoining landowners share equally in the cost of maintaining or replacing a boundary fence that benefits both properties.

Retaining walls over 3 feet in height (measured from top of footing to top of wall) require a building permit in unincorporated San Diego County. Walls supporting a surcharge (additional weight or structures above) also require permits regardless of height.

All swimming pools in unincorporated San Diego County must have safety barriers at least 60 inches high with self-closing, self-latching gates per the California Building Code and Swimming Pool Safety Act. Gates must open away from the pool with latches at least 60 inches above ground.

In unincorporated San Diego County, fences under 6 feet generally do not require a building permit per County Code Section 91.1.105.2. Fences over 6 feet, retaining wall-fence combinations, and fences in special areas (wildfire zones, scenic corridors) require permits.

All swimming pools in unincorporated San Diego County must comply with the California Swimming Pool Safety Act and County Code Section 92.1.3109.3. At least one approved safety feature must be inspected before the pool is filled. Pools include in-ground, above-ground, and wading pools over 18 inches deep.

Hot tubs and spas in unincorporated San Diego County must meet the California Swimming Pool Safety Act requirements. Self-contained hot tubs with ASTM-compliant locking safety covers are exempt from barrier requirements. Permanently installed spas require building permits.

Above-ground pools containing water over 18 inches deep are regulated in unincorporated San Diego County. They must meet safety barrier requirements. Pool walls may satisfy barrier requirements if they meet height and anti-climbing standards. Permits may be required.

Every in-ground swimming pool in unincorporated San Diego County requires a building permit from County PDS. The permit process includes plumbing, electrical, fencing/barrier, and pool inspections. Above-ground pools over 18 inches deep also need permits.

Pool fencing in unincorporated San Diego County must be at least 60 inches high, with self-closing/self-latching gates opening away from the pool. Maximum ground clearance of 2 inches. No gaps allowing passage of a 4-inch sphere. Identical to pool-barriers entry.

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.

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.

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.

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.

San Diego County's 2023 Consolidated Fire Code strictly regulates fire pits in unincorporated areas. Recreational fires must be in approved containers, 15 feet from structures, and attended at all times. Backcountry and VHFHSZ areas face additional restrictions, especially during Red Flag Warnings.

Open burning in unincorporated San Diego County is heavily regulated by the San Diego County Air Pollution Control District (APCD) and the County Fire Authority. Agricultural burning requires APCD permits. Residential yard waste burning is generally prohibited. Recreational fires in approved containers may be allowed.

Tree removal in unincorporated San Diego County is regulated by the Resource Protection Ordinance and defensible space requirements. Significant native trees may require permits for removal. Trees in defensible space may need to be removed or pruned with branches 6 feet above ground. Stumps must be cut no higher than 8 inches.

San Diego County enforces outdoor water use restrictions in unincorporated areas. Landscape irrigation is limited to before 10 AM and after 6 PM. Runoff, overspray, and watering impervious surfaces are prohibited. Turf that cannot be irrigated without waste is not allowed in new landscaping.

Tree trimming in unincorporated San Diego County is required for defensible space maintenance (branches pruned to 6 feet above ground), utility clearance, and road visibility. Protected native trees may require consultation with County PDS before major pruning.