St. Louis County, MO Fence Regulations: Material Restrictions (2026)

131, provides that electrically charged fences are prohibited and that barbed wire, razor ribbon, and similar materials are prohibited on all new fence installations, countywide. The same section requires a building permit for any new fence or fence replacement under Sections 105 and 109, and bars fencing on a corner lot from sitting inside the sight-distance triangle. 8, layers district-specific rules on top of the building code: barbed wire is barred outright in the "PS" Park and Scenic, "NU" Non-Urban, "KP" Karst Preservation, and every "R" Residence District, while "C" Commercial Districts require decorative fencing in front yards and a sight-proof, decorative buffer fence where commercial land meets those residential-type districts.

Only "M" Industrial Districts may use barbed wire adjacent to those protected districts, and only if screened with dense landscaping approved by the Director of Planning, with the lowest strand kept at least seven feet above the ground, the same height floor used in the building code's own industrial exception. Beyond industrial screening, the building code allows barbed wire atop fencing for agricultural sites containing livestock and for USDA-licensed, AZA-accredited zoological institutions maintaining animal enclosures, and allows barbed wire or razor ribbon atop fencing for prisons, jails, and similar correctional facilities where the lowest strand again sits at least seven feet above grade.