Neenah, WI Accessory Structures: ADU Rules (2026)

Wisconsin authorizes cities to regulate the use, density, height, bulk, and lot coverage of buildings and the use of land through zoning under Wis. Stat. Sec. 62.23(7). Neenah exercises that authority through Chapter 26 of the Code of Ordinances (Zoning), which establishes residential, business, and other districts in Article VI - Zoning Districts and which sets accessory use and structure standards within those districts. Neenah's code does not have a stand-alone state-mandated ADU ordinance comparable to California or Oregon: any second dwelling unit (attached, detached, or junior) must be authorized as a permitted or conditional use within the underlying zoning district under Chapter 26, and must comply with the lot area, setback, height, lot coverage, off-street parking, and accessory-structure provisions of that chapter. Two-family and multi-family dwellings have their own dimensional and parking standards. Detached accessory structures (sheds, garages, accessory buildings) are regulated separately for size, height, setback, and lot coverage and may not be used as separate dwellings unless the zoning district permits it. Any new dwelling unit also requires a Wisconsin Uniform Dwelling Code (UDC) building permit through the city Inspection Division and must meet state plumbing, electrical, and energy code requirements. Owners should confirm current Chapter 26 text on the Municode site before designing a project, because cities periodically amend zoning to address ADUs.