Merced, CA Fence Regulations: Retaining Walls (2026)

Unlike fences, retaining walls are a structural item governed by the California Building Code (CBC), adopted locally through Merced's Title 17 (Buildings and Construction). Under 2022 CBC Section 105.2, a building permit is not required for retaining walls that are not over 4 feet in height measured from the bottom of the footing to the top of the wall, unless supporting a surcharge or impounding Class I, II, or IIIA liquids. In practice this means any retaining wall taller than 4 feet (footing to top), or any wall of any height holding back a slope, driveway, parking area, or building load (a surcharge), requires a building permit from the City. Engineered plans, and sometimes a soils report, are typically required for walls over 4 feet. A retaining wall combined with a fence on top is evaluated for both the wall (CBC) and the fence (MMC 20.30 height limits). Retaining wall placement must respect zoning yard/setback requirements and may not encroach into the public right-of-way or a public use easement. Permits are issued through the City's Development Services / Building Division and online permit portal.