Boone County, IN Building Setbacks & Zoning: Lot Coverage Limits (2026)

Table 3 of Section 157.007(B), Residential Uses and Requirements for Single Family, sets maximum lot coverage by zoning district: AG and RE districts are capped at 50%, R1 and R2 at 60%, and R3, R4, LB, U5, GB, FS and A5 at 70%. Lot coverage itself is defined in Section 157.005 as the total ground area within the lot covered by the primary structure plus accessory structures such as decks, patios, swimming pools, garages, carports and storage sheds, excluding driveways, sidewalks, and fences or walls not attached to a roof.

The same table sets a uniform 35-foot maximum building height across every listed district and a 5,000-square-foot minimum lot size where public sewer is available. For accessory dwelling units specifically, Section 157.063(C) cross-references this same lot-coverage cap, confirming that adding an ADU does not raise the ceiling: the maximum lot coverage standard of the subject zoning district still applies. The Area Plan Commission checks lot coverage against Table 3 when it reviews improvement location permit applications for new construction or additions.