Boone County, IN Building Setbacks & Zoning: Structure Height Limits (2026)

Table 3 of Boone County Code § 157.007(B), covering single-family residential uses, sets the maximum height of buildings at 35 feet in every district it lists: AG, RE, R1, R2, R3, R4, LB, U5, GB, FS and A5. That flat 35-foot number holds for the Agricultural District as well as the county's residential and limited-business zones, so a homeowner's new two-and-a-half-story house or detached garage runs into the same ceiling regardless of which district it sits in. Section 157.026 then carves out two exceptions to that district-by-district height rule.

A farm building may be erected or changed to any height necessary for its operation, though any such structure, whatever its height, still has to secure an improvement location permit (ILP) under § 157.140 before construction. Spires and church steeples are exempted outright and may be erected or changed to any height that is not otherwise prohibited, with no ILP-driven ceiling at all. Multi-family and commercial buildings are not held to the same 35-foot line: Table 4 under § 157.007(C) allows up to 50 feet for multi-family dwellings, and Table 6 under § 157.007(E) allows up to 75 feet in the CR, I1 and I2 districts, so the 35-foot cap discussed here is specific to single-family homes and their accessory structures.

The Area Plan Commission Director reviews height compliance on every ILP application, and a structure raised past 35 feet without qualifying as a farm building or a steeple is a Chapter 157 violation subject to the county's general penalty at § 10.99. Lebanon, Zionsville, Whitestown, Jamestown and Thornton set their own height limits.