Racine County, WI Accessory Structures: ADU Rules (2026)

Wis. Stat. §59.69 authorizes Wisconsin counties to adopt zoning over unincorporated territory, with each town required to approve the county ordinance for it to apply. Racine County's zoning authority is codified in Chapter 20 of the County Code of Ordinances and administered by the Development Services Division of Public Works and Development Services. Chapter 20 establishes residential districts (R-1, R-2, R-3, R-4) where one-family detached dwellings are the principal permitted use; the ordinance does not contain a stand-alone 'accessory dwelling unit' definition, so a second dwelling unit is generally treated either as a two-family use (allowed only in districts that permit two-family dwellings) or as a non-permitted use unless authorized as a conditional use by the County Land Use Planning Commission. Accessory buildings under Chapter 20 are limited to uses customarily incidental to the principal use, must meet district setback rules, and may not be used for human habitation unless they qualify as a permitted dwelling unit. Residential dwellings must connect to an approved POWTS (private onsite wastewater treatment system) under Wis. Admin. Code chs. SPS 383-385 if outside a sanitary district. Towns within Racine County that have adopted county zoning include Burlington, Dover, Norway, Raymond, Waterford, and Yorkville; the City of Racine, Burlington, and incorporated villages set their own ADU rules. Builders should always confirm with the Racine County Development Services Division (262-636-3320) whether a proposed unit is allowed by right, by conditional use, or only after rezoning.