Riverside County, CA Fence Regulations: Retaining Walls (2026)
Key Facts
- Permit-exempt height
- 4 ft, footing to top
- Exception
- surcharge or hazardous-liquid walls
- Enforcing agency
- County Building and Safety Dept.
- Applies to
- unincorporated area only
Summary
Retaining walls up to 4 feet, measured footing to top, don't need a building permit in unincorporated Riverside County. Taller walls, or any wall holding back a surcharge or hazardous liquids, require one from Building and Safety before work starts.
105.2 Work exempt from permit... Permits shall not be required for the following: Building: ... 4. Retaining walls that are not over 4 feet (1219 mm) 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.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 84 Update 1).
Full Breakdown
The County's amended California Building Code Section 105.2 exempts retaining walls not over 4 feet in height, measured from the bottom of the footing to the top of the wall, from permit requirements. That exemption disappears if the wall supports a surcharge (extra load behind it) or impounds Class I, II or IIIA liquids: those need a permit regardless of height. The rule sits inside Riverside County Code Chapter 15.04, which adopts and locally amends the 2025 California Building Code for the unincorporated area only; incorporated cities like Riverside, Temecula and Palm Desert enforce their own building codes.
Violations & Fines
Building a wall that needed a permit without one triggers the county's construction-without-permit process: the owner must apply for the permit after the fact and the building official can require non-destructive or destructive testing to confirm the completed wall meets code before it's approved.
Frequently Asked Questions
Do I need a permit for a low retaining wall in unincorporated Riverside County?
What if my wall is over 4 feet or holds back water or another liquid?
Sources & Official References
Other rules in Riverside County
California rules heatmap·Compare Riverside County to another location·View the California fence regulations overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.