Placer County, CA Fence Regulations: Retaining Walls (2026)

Placer County regulates retaining walls through both its Zoning Ordinance (Section 17.54.030, Landscaping and fencing) and its Building Code. The zoning code addresses the combined height of a retaining wall plus a fence on top: county code provisions indicate that a retaining wall and fence may be up to eight feet in height when located in a side or rear yard area and not within any required front or street-side setback. Within front and street-side setbacks, the lower fence-height limits in Section 17.54.030 control, so a retaining wall topped by a fence in those areas is more restricted and may require a variance. Separately from zoning, a retaining wall that supports a surcharge or exceeds the height threshold in the California Building Code requires a building permit and may require engineered plans; the CBC permit exemption that applies to ordinary fences does not extend to structural retaining walls supporting significant loads. Because retaining-wall rules interact with grading, drainage, easements, and slope, and because exact thresholds depend on the wall's height and whether it carries a surcharge, owners should confirm requirements with Placer County CDRA Building Services and Engineering before construction.