Whittier, CA Fence Regulations: Retaining Walls (2026)

030(D) set the height and setback rules for retaining walls by yard and lot condition. On an above-grade lot, a front-yard retaining wall tops out at 42 inches, and any wall over 3 feet must be set back 4 feet from the right-of-way with the setback space landscaped; additional stacked walls above the first are allowed at the same 42-inch cap if each is set back another 4 feet with landscaping between them. On a below-grade lot, retaining walls or crib-wall systems in the front yard setback may reach 6 feet when not visible from the street, set back 4 feet from the property line with a non-view-obscuring safety fence on top sized per the California Building Code; the combined wall-and-fence height cannot exceed 8 feet measured from the lowest finished grade.

In the interior side yard, any freestanding wall, fence or retaining wall caps at 6 feet, and on a grade-differential lot the lower-elevation owner may build a combination wall up to 8 feet, or the higher-elevation owner up to 6 feet using a decorative material from the city's approved retaining wall palette. 040 (Sec. 2) exempts only walls or fences not over 18 inches high, and expressly states that walls supporting a surcharge are not exempt from permit regardless of height, meaning nearly every true retaining wall needs a Building Official permit. Walls facing the Greenway Trail require an engineered design before a building permit is issued.