San Diego County, CA Fence Regulations: Retaining Walls (2026)
Key Facts
- Permit-exempt threshold
- Retains ≤3 ft soil, ≤6 ft total
- Above threshold
- Building permit required before construction
- Governing section
- County Code § 91.1.105.2
- Scope
- Unincorporated San Diego County only
- Enforcement
- Building official reviews and issues permits
Summary
In unincorporated San Diego County, retaining walls over 3 feet of retained soil or 6 feet total height need a county building permit before construction begins.
A building permit shall not be required for the following... (7) Walls that retain not over three feet of soil as measured from the top of the footing to top of retained soil, are not more than 6 feet in total height as measured from the lowest finished grade, and have a level backfill with no other structures within 6 feet and not supporting a surcharge or impounding flammable liquids.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-141: Administrative: Current through Ord. No. 11007 (N.S.), effective 7-10-26 | Regulatory: Current through Ord. No. 11008 (N.S.), effective 7-24-26).
Full Breakdown
San Diego County's building code exempts small retaining walls from permitting: under Section 91.1.105.2(a)(7), a wall retaining no more than 3 feet of soil (measured footing to top of retained soil) and no more than 6 feet in total height, with level backfill, no structures within 6 feet, and no surcharge or flammable-liquid load, needs no building permit. Anything taller or supporting extra load requires the building official to review and issue a permit, per Section 91.1.105, before work begins. This applies to unincorporated areas only; incorporated cities like the City of San Diego set their own retaining wall standards.
Violations & Fines
Building without a permit for a retaining wall exceeding these thresholds is a code violation; the county can red-tag the work, require removal or retrofit, and impose stop-work orders and citations.
Frequently Asked Questions
Do I need a permit for a retaining wall in unincorporated San Diego County?
Which agency issues the retaining wall permit?
Sources & Official References
Other rules in San Diego County
California rules heatmap·Compare San Diego 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 If you notice an error or outdated information, let us know.