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.
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Side-by-side rule comparisons with other cities in Orange County.
See how other cities in Orange County handle retaining walls.
See how Midway City's retaining walls rules stack up against other locations.
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