Retaining walls in unincorporated Orange County require building permits and engineered plans when retaining level earth over 4 feet, retaining any slope, or subject to surcharge loads. The OC Grading Manual and Building Code govern design and construction standards.
Under Orange County building requirements, retaining walls that retain level earth more than 4 feet in height, walls impacted by surcharge loads, or walls retaining any slope must have engineered structural plans and a building permit. The licensed engineer or architect who designs the wall must sign the design plans, plot plan, and structural calculations. Walls over 6 feet in height always require engineering. Retaining walls under 4 feet retaining level earth without surcharge are generally exempt from permit requirements but must still meet setback requirements. The OC Grading Manual (2017 Edition) provides additional standards for grading associated with retaining wall construction. Drainage must be addressed in the engineering design to prevent hydrostatic pressure buildup.
Unpermitted retaining walls may receive stop-work orders and require retroactive permits with double fees. Structurally deficient walls may be ordered demolished at the owner's expense. Failed retaining walls causing property damage may trigger civil liability.
Orange County, CA
Unincorporated Orange County exempts one small detached non-habitable accessory structure - a shed - per 7,200 square feet of building site area from accesso...
Orange County, CA
Carports in unincorporated Orange County are governed by Section 7-9-70.3(d) of the Codified Ordinances, which requires carports to comply with main-building...
Orange County, CA
Unincorporated Orange County allows the conversion of an existing garage, carport, or accessory structure into an accessory dwelling unit (ADU) under Section...
Orange County, CA
Unincorporated Orange County requires every pool/spa deeper than 18 inches to be enclosed by a barrier at least 60 inches (5 ft) high under California Health...
Orange County, CA
Unincorporated Orange County allows ADUs on any residentially zoned lot under OC Zoning Code (Title 7, Division 9) and California Government Code §65852.2 (A...
Orange County, CA
Orange County does not levy a general gross-receipts business tax in unincorporated areas; businesses obtain a county business license tied to zoning, while ...
See how Orange County's retaining walls rules stack up against other locations.
Help us keep this page accurate. If you notice an error or outdated information, let us know.