Sun Prairie, WI Building Setbacks & Zoning: Setback Rules (2026)

24, Bulk Regulations, ties every setback to the specific dwelling-unit type used on the lot rather than to the zoning district alone, because different lot sizes are permitted across overlapping districts. For the common 10,500-square-foot single-family detached house, permitted by right in the SR-4, MR-8 and UR-12 districts and as a conditional use in ER-1, the front or street-side setback to the house is 45 feet from an arterial street but only 20 feet from a collector or local street; an attached garage gets the same arterial setback but a 30-foot minimum from a collector or local street.

Side setbacks run 10 feet to the house or attached garage, with a combined total of both sides of at least 22 feet, and the rear setback to the house or garage is 30 feet. Accessory structures get tighter margins: 5 feet from both side and rear lot lines. 050. Larger-lot dwelling types carry much wider setbacks under the same table: a 1,000,000-square-foot single-family lot requires 100 feet on the sides and rear, and a 175,000-square-foot lot requires 40 feet on the sides and rear, so the applicable figure depends entirely on which dwelling-unit type and lot size governs the parcel.