Royal Oak, MI Accessory Structures: ADU Rules (2026)

The City of Royal Oak's only accessory-unit provision is § 770-71, Senior accessory housing, and it is narrower than a typical ADU ordinance: it lets a single-family dwelling incorporate, within or attached to the existing house, one additional unit reserved for an elderly related person in a residential district. There is no equivalent right to add a general accessory apartment for a tenant or a caretaker who is not an elderly relative. The additional unit's floor area is capped at 600 square feet, though the Plan Commission can allow a slightly larger one-bedroom unit if the existing house layout can be reasonably and safely converted.

The homeowner must provide one dedicated off-street parking space for the senior unit, on top of whatever parking already serves the main house. Every bulk and setback requirement of the underlying residential zoning district still applies to the property; the accessory unit gets no special exemption from those standards. Because the unit is created through a special land use permit rather than a by-right addition, the applicant must follow the special land use permit procedure, and the City reviews the permit for continued compliance, addressed further under the ownership and use-restriction rules found within the same section. Community Development and the Building Division administer the permit and the required certificate of occupancy.