Wyoming, MI Accessory Structures: ADU Rules (2026)

Sec. 90-334 of the Wyoming Zoning Ordinance, added by Ordinance No. 3-25 on January 21, 2025, defines an accessory dwelling unit (ADU) as a house or apartment that shares a building lot with, and is incidental to, a larger primary dwelling unit, and permits ADUs only in single-family zoned uses such as the R-1 through R-7 residential districts. No more than one ADU is allowed per lot. Size is bracketed: the minimum floor area is 350 square feet, referencing the dimensional table at Sec. 90-204, and the maximum is whichever is smaller of 850 square feet or the remaining square footage allowed under the lot's maximum lot coverage.

An ADU may hold no more than one bedroom. It must be contained entirely within, or attached directly to, the primary structure, ruling out a detached backyard cottage, and it must use the same setbacks that apply to the primary structure rather than separate accessory-structure setbacks. The unit cannot have its entrance on the front face of the primary structure. Each ADU also requires its own dedicated, unobstructed off-street parking space; a space blocked by another vehicle's parking space does not satisfy the requirement. Two additional conditions in the same section, owner-occupancy inspections and a short-term-rental ban, are addressed on their own pages. Site plan and building permit review by the city planner's office and the chief building official apply before construction.