Accessory Structures in West Allis, WI (2026)
2 verified accessory structures rules for West Allis, Wisconsin, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
West Allis regulates accessory buildings under Chapter 19 (Zoning) of the Revised Municipal Code, adopted under the city zoning authority of Wis. Stat. Sec. 62.23. Sec. 19.42 (Residential Accessory Buildings) caps detached accessory structures at 50% of the principal building area, not to exceed 800 square feet, with a maximum exterior wall height of 20 feet. Setback minimums include 10 feet from the principal building, 3 feet from side lot lines, and 3-5 feet from rear lot lines depending on alley adjacency. The West Allis Zoning Code does not establish a separate by-right accessory dwelling unit (ADU) class in the manner of cities like Appleton; a habitable second dwelling unit on a single-family lot generally requires zoning interpretation by the Planning and Zoning Department.
Accessory Dwelling Unit Rules (West Allis, WI)
Some RestrictionsShed Rules
Sheds in West Allis are 'Other Accessory Buildings' under Section 19.42 of the West Allis Zoning Code. They are limited to 300 square feet, 15 feet in height, must sit at least 3 feet from any side or rear lot line (5 feet if the rear abuts an alley), at least 10 feet from the principal dwelling, and at least 60 feet from the front lot line.
Shed Rules in West Allis
Some RestrictionsLooking for Milwaukee County county-wide rules?
County ordinances apply to unincorporated areas and may supplement West Allis city rules.
Accessory Structures in Milwaukee County →