Boone County, IN Fence Regulations: Retaining Walls (2026)
Key Facts
- Permit required
- None; retaining walls exempt from ILP
- Governing section
- Boone County Code § 157.021(C)
- Enforcing agency
- Area Plan Commission Director
- Default penalty
- Up to $2,500 first, $7,500 repeat (§ 10.99)
- Applies in
- Unincorporated Boone County only
Summary
In unincorporated Boone County, Indiana, retaining walls are on the county's own list of exempt accessory structures: Board of Commissioners' Code § 157.021(C) lets homeowners build them in any required yard without an improvement location permit (ILP). Fences, walks, curbs and drainage installations share the same exemption.
Any person, firm or corporation who violates any provision of this code for which another penalty is not specifically provided shall, upon conviction, be subject to the following: (1) A fine not exceeding $2,500 for the first violation; and (2) A fine not exceeding $7,500 for second and subsequent violations, except for violations of ordinances regulating traffic and parking. ... (C) The following accessory structures are permitted in all districts and may be installed in any required yard without an ILP: landscape vegetation, swing sets, children’s tree houses, bird baths, bird houses, curbs, fences, lamp posts, mail boxes, name plates, parking spaces, utility installations for local services, retaining walls, walks, drainage installations, housing for domestic pets provided it is not for profit and does not constitute a kennel as defined in this chapter.
Full Breakdown
Boone County Code § 157.021 governs accessory structures across every zoning district in unincorporated Boone County. Retaining walls are named on the county's no-ILP list at § 157.021(C), alongside fences, curbs, mailboxes, walks and drainage installations, so a homeowner does not file for an improvement location permit before building one. But § 157.021(B) still requires every accessory structure, walls included, to stay clearly subordinate in height, area, bulk and purpose to the primary structure on the lot. If a wall's siting is tied to a broader project, such as grading for a new home or garage, it is still reviewed as part of that project's own Improvement Location Permit under § 157.140, which the Area Plan Commission (APC) Director issues before construction starts.
Since Chapter 157 sets no dedicated zoning penalty, an unpermitted structure that runs afoul of the subordinate-height rule or a setback falls under the county's general penalty clause, § 10.99: up to $2,500 for a first violation and up to $7,500 for repeat violations, with each day counted separately. Homeowners in Lebanon, Zionsville, Whitestown, Jamestown and Thornton have their own municipal codes and are not covered by this county section.
Violations & Fines
Boone County has no zoning-specific fine for accessory structures, so a violation of Chapter 157, for example a wall that isn't subordinate to the primary structure or that crosses a setback, defaults to the general penalty in § 10.99: a fine of up to $2,500 for a first conviction and up to $7,500 for each subsequent violation, with every day the violation continues counted as a separate offense.
Frequently Asked Questions
Do I need a permit to build a retaining wall in unincorporated Boone County?
Is there a height limit for a retaining wall?
Who enforces Boone County's accessory-structure rules?
Does this rule apply inside Lebanon or Zionsville?
Sources & Official References
Other rules in Boone County
Compare Boone County to another location·View the Indiana fence regulations overview
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