Johnson County, IA Fence Regulations: Retaining Walls (2026)
Key Facts
- Setback trigger
- Walls over 4 feet tall
- Setback formula
- 1.5x wall height
- Guardrail trigger
- Walls over 30 inches
- Right-of-way walls
- Exempt from setback
- First-offense fine
- Up to $750
- Applies to
- Unincorporated county only
Summary
In unincorporated Johnson County, a retaining wall over 4 feet tall must sit back from the property line at least 1.5 times its own height, measured from footing to the top of the wall. Walls over 30 inches also need a guardrail in several situations.
F. Retaining Walls. The following standards shall apply to retaining walls. For permitting requirements, refer to Chapter 8:6 Building Code. 1. Setback Regulations. Retaining walls greater than four (4) feet in height must be setback a minimum of 1.5 times the height of the wall. Retaining wall height is determined by measuring from the top of the foundation to the tallest portion of the wall. 2. Guardrail Requirements. Retaining walls greater than 30 inches in height must have a guardrail in the following circumstances: The retaining wall is considered a part of another structure. The retaining wall is adjacent to or in close proximity to a walking area or livable area (e.g. walking path, patio, or bike path). The retaining wall is a part of a multifamily, commercial, or industrial development. 3. Retaining walls located in the right-of-way that are necessary to facilitate installation of common infrastructure are exempt from retaining wall setback requirements.
Official source re-checked September 7, 2026: the cited page had not changed since it was quoted.
Full Breakdown
25(F). 5 times the wall's height, with height measured from the top of the footing/foundation to the wall's tallest point, not from grade. That formula scales fast: a six-foot wall needs a nine-foot setback, and a ten-foot wall needs fifteen feet of clearance from the lot line. Separately, any retaining wall taller than 30 inches must include a guardrail if the wall functions as part of another structure, sits next to or near a walking path, patio, bike path, or other livable area, or is part of a multifamily, commercial, or industrial development.
Walls built in the road right-of-way solely to support common infrastructure installation are exempt from the setback rule, since utility work often can't avoid that zone. 27 require the fee to be paid to the Zoning Administrator before any permit issues, with a doubled fee charged if work starts before the permit is approved. Violations of these standards are enforced under Chapter 8:8 as a County Infraction.
Violations & Fines
A retaining wall built without the required setback or guardrail is enforced as a County Infraction under UDO section 8:8.3, a civil offense carrying a penalty of up to $750 for a first offense and up to $1,000 for any repeat violation of the same section by the same person or business. Each day the noncompliant wall remains can count as a separate offense, and the County may also seek abatement or injunctive relief in addition to the civil penalty. Starting work before a permit issues doubles the applicable permit fee under section 8:1.27.
Frequently Asked Questions
How is retaining wall height measured for the setback rule?
Do I need a permit to build a retaining wall in unincorporated Johnson County?
When does a retaining wall need a guardrail?
Sources & Official References
Other rules in Johnson County
Compare Johnson County to another location·View the Iowa fence regulations overview
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