Accessory Structures in Sun Prairie, WI (2026)
2 verified accessory structures rules for Sun Prairie, Wisconsin, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Sun Prairie allows accessory dwelling units (ADUs) on residential properties under Title 17 (Zoning) of the Sun Prairie Municipal Code. The Plan Commission recommended approval of an ADU ordinance amendment, with first reading at the City Council on April 21, 2026 and a recommended maximum size of 1,000 sq ft. Both attached and detached ADUs are permitted in residential districts (including SR-4, MR-8, and UR-12) without a conditional use permit. ADUs are exempt from maximum density and floor area ratio calculations, no additional parking is required, and owner occupancy is not mandated. ADUs use reduced rear-yard setbacks applicable to accessory structures.
Accessory Dwelling Unit Rules (Sun Prairie, WI)
Few RestrictionsShed Rules
Utility sheds 80 square feet or smaller (roughly 8 by 10 feet) do not require a building permit in Sun Prairie. Sheds over 80 square feet require both a building permit and a zoning permit from the Building Inspection Division. Sheds must sit at least 5 feet from any side or rear lot line, cannot be located between the principal building and the street frontage, and any shed within 10 feet of the house must include fire separation. Garages or accessory buildings exceeding 1,000 square feet require a conditional use permit.
Shed Rules in Sun Prairie
Some RestrictionsCity of Sun Prairie — Garages/Sheds Regulations
Sheds 80 square feet (8 by 10 feet) or under in size do not require a permit. Sheds shall be secured to the ground or floor. Sheds are not allowed in front or street yards. Sheds must be located at least 5 feet from side and rear lot lines. If a shed is within 10 feet of the house it requires fire separation. Garages in excess of 1,000 square feet require a conditional use permit. Accessory str...
Looking for Dane County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Sun Prairie city rules.
Accessory Structures in Dane County →