Chicago, IL Fence Regulations: Retaining Walls (2026)

While Chicago's Building Code does not contain a standalone retaining-wall fence chapter, several provisions govern walls and wall-like fences. Section 13-96-135 (Building clearances; required openings) provides that any portion of a fence directly adjacent to the public way located on the same lot as a Class A residential unit that is a 'large building' (as defined in Section 13-160-070) must be a minimum of 15 feet from the nearest portion of that large building and must contain a gate, opening, or other true means of ingress and egress, preserving emergency access. All fences and walls must resist a horizontal wind pressure of not less than 30 pounds per square foot under Section 13-96-150. Solid masonry walls and any wall-type fence more than five feet in height require a permit from the building commissioner under Section 13-32-200, and masonry work generally must be performed by a licensed mason. Within required setbacks, a wall is treated like a fence under Zoning Section 17-17-0309: a solid wall more than 20% opaque may encroach up to 4.5 feet in the front setback and up to 6 feet in side and rear setbacks. Retaining walls that hold back earth may additionally trigger structural review under the Building Code's foundation and structural-design divisions.