Green Bay's Accessory Structures: The Rules That Matter

Every city handles accessory structures a little differently. In Green Bay, Wisconsin, there are 2 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.

ADU Rules

Green Bay allows one accessory dwelling unit per lot behind the main house, capped at 1,000 square feet, but only with a conditional use permit and owner-occupancy of one unit.

Key details: Cap: One ADU per parcel. Size limit: 1,000 sq ft max. Occupancy: Owner must live on-site. STR use: ADUs cannot be short-term rentals. Approval: Conditional use permit required.

Building or renting out an unapproved ADU is a zoning violation; the City can require removal or bring the property into compliance through standard Code enforcement, since no separate ADU penalty is set.

This is one of the stricter rules in Green Bay's municipal code. If you are unsure whether your situation complies, it is worth checking with the city before proceeding.

Shed & Carport Rules

Green Bay allows two detached accessory structures on a one- or two-family lot under Section 44-590 and Table 44-4. The first may reach 1,000 square feet per dwelling unit and the second 200 square feet. Both are capped at 16 feet tall with 10-foot side walls, and sit 25 feet from the front lot line and 4 feet from the side and rear lines.

Key details: Structures allowed (one- or two-family): 2 detached. Maximum size: 1,000 sq. ft. per dwelling unit; 200 sq. ft. second. Maximum height: 16 feet, side walls 10 feet. Setbacks: Front 25 ft, side 4 ft, rear 4 ft. Between structures: 3 feet, wall to wall.

Section 44-197 makes it unlawful to use or improve any structure in violation of Chapter 44, and declares a nonconforming building a nuisance per se that the City can ask a court to abate or remove. If the owner has not complied or signed a written compliance agreement within 15 days after the Zoning Administrator mails written notice, the City Attorney can file for an injunction. Section 44-198 applies the Section 1-6 penalty and counts each day as a separate violation.

The Bottom Line

Green Bay's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Green Bay is broadly strict or permissive.

Keep in mind that Green Bay can amend these rules at any council meeting. For the most current version of any rule mentioned here, check the specific ordinance page, which shows when its source was last checked.