Kaukauna, WI Accessory Structures: ADU Rules (2026)

Kaukauna's zoning authority is Wis. Stat. Sec. 62.23. Chapter 17 of the Kaukauna Municipal Code is the Zoning Code. Sec. 17.03 defines key terms, including 'accessory use or structure' ('a use or structure on the same lot with the principal use or structure and of a nature customarily incidental and subordinate to the principal use or structure') and 'utility storage structure' (described as 'uninhabited' and to be 'located in the rear yard of the principal structure'). Sec. 17.07(6)(a)2.b establishes that a deck not exceeding 200 sq ft adjacent to the principal structure is not treated as an extension. Residential district standards (Chapter 17 District Regulations) include: RSF Residential Single-Family (Sec. 17.16) - 7,200 sq ft minimum lot, 60 ft minimum width, 25 ft front setback (with averaging exception), 7 ft side setback, 20 ft rear setback, 35 ft max height, 30 percent max lot coverage; RTF Residential Two-Family (Sec. 17.18) - 9,000 sq ft minimum lot, 70 ft minimum width, 25 ft front setback, 7 ft side setback, 25 ft rear setback, 35 ft max height; RMF Residential Multifamily (Sec. 17.19) - multifamily structures limited to three stories or 45 ft. Because no separate ADU section exists, a second dwelling unit on a single-family lot is generally not authorized under Sec. 17.16; owners must either be in RTF/RMF zoning or pursue rezoning, conditional use, or a zoning text amendment. Detailed accessory structure dimensional standards are addressed in Sec. 17.32 (Accessory uses and structures and accessory parking and storage). Wisconsin 2025 Senate Bill 473 has been proposed to require statewide ADU allowances but has not been enacted as of this writing.