St. Clair County, IL Fence Regulations: Height Limits (2026)

Section 40-5-5 of the St. Clair County Zoning Ordinance governs fences, walls, and hedges "used for any purpose" in every zoning district in the unincorporated county. Subsection (A) sets the corner-lot visibility rule: on any corner lot, no obstruction taller than two feet above the adjacent curb elevation may be planted, placed, or erected inside the triangular "restricted area" shown as Figure 1 in Section 40-2-3, so a homeowner at an intersection cannot fence, hedge, or otherwise block sightlines for oncoming traffic. Subsection (D) sets the general height standard: a fence, wall, or hedge may run along any lot line at any height up to six feet without triggering additional setback review, but once it exceeds six feet it must be pulled back to meet the "minimum yard requirements" of the underlying zoning district, meaning a tall fence in the front, side, or rear yard has to sit behind the same line a principal building would.

Subsection (C) separately bars any permanent fence or retaining wall inside a public street or alley right-of-way unless the County Board specifically authorizes it, and it makes the property owner financially responsible for removing or replacing any fence built across a public easement or drainage ditch when maintenance requires it. Property owners who believe the standard yard setback creates a hardship for a taller fence can petition the Zoning Board of Appeals for an area/bulk variance under Article XI; the filing fee for that variance is $300, per the Schedule of Filing Fees in Section 40-11-9.