Retaining walls in unincorporated LA County under 4 ft from footing to top are exempt from building permits unless supporting a surcharge. Walls in required yards cannot exceed 6 ft. In coastal areas, retaining walls must be terraced and landscaped with native species before the rainy season (Oct 15-Apr 15).
Retaining walls in unincorporated LA County under 4 feet from footing to top of wall are exempt from building permits but must still comply with setback requirements. Walls over 4 feet require a building permit from Building & Safety and engineered structural plans signed by a licensed civil or structural engineer. Surcharge loads (driveways, structures above the wall) reduce the permit-exempt height threshold. Multiple tiered walls with less than the height of the lower wall between them are measured as a single wall. Retaining walls in hillside areas may require geotechnical investigation.
Building a retaining wall over 4 feet without a permit and engineering plans is a building code violation. Stop-work orders are issued immediately. Retroactive permits require double fees plus engineering review. Walls that fail or cause damage to adjacent properties create civil liability for the owner. Administrative fines of $250-$1,000 per day apply until a permit is obtained or the wall is removed.
Altadena, CA
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Altadena, CA
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Altadena, CA
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