Minnetonka, MN Accessory Structures: ADU Rules (2026)

Minnetonka City Code § 300.16, subd. 3(d) sets the standards for accessory dwelling units. Section 300.01 defines an ADU as a secondary dwelling unit on the same property as a principal dwelling unit, with provisions for living independent of the principal dwelling, such as areas for sleeping, cooking, and sanitation, as determined by the city planner. The R-1 and R-2 district sections list accessory dwelling units among their conditional uses, and subdivision 2 of § 300.16 says no conditional use permit can be granted unless the City Council determines that every general standard is met.

The general standards allow ADUs only on properties zoned R-1, R-1A and R-2, with no more than one ADU per property. Adequate off-street parking is required for both units, in a garage, carport or paved area not within a required driveway turnaround, and no more than four vehicles can be parked or stored outside on the property, not counting occasional guests. The ADU and its lot remain subject to every provision of the ordinance for single-family dwellings, including the shoreland, wetland, floodplain and nuisance ordinances, and the most restrictive provision applies in a conflict.

Construction standards depend on the district. On R-1 or R-1A lots an ADU can be attached or detached. On R-2 lots it must be attached, and an attached ADU includes one contained within an existing principal structure. Any ADU must be no larger than 1,000 square feet in total area or 35 percent of the floor area of the principal dwelling, whichever is less, although the City Council can approve more where there is no undue adverse impact on neighbors. A detached ADU can never be 200 square feet or less. Every ADU must be served by municipal water, municipal sanitary sewer, and gas and electric utilities through service lines shared with the principal dwelling, must meet all building, housing, electrical, plumbing and mechanical codes, cannot add a curb cut unless the city engineer approves, and must be registered with the Minnetonka police and fire departments before anyone occupies it.