Is there a minimum house size in Royal Oak?

Yes. In 1F and 1FL, the smallest adjacent single-family dwelling establishes the minimum usable floor area, subject to a floor of 1,000 square feet in 1F and 1,300 square feet in 1FL. The comparison follows the prescribed front/side property-line extensions, crossing no more than one street right-of-way, and excludes rear neighbors (§ 770-23A).

For a two-family dwelling, minimum usable area per unit is based first on the smallest individual unit in adjacent two-family residences. Only if there are no such adjacent two-family residences does the 80% calculation based on adjacent single-family dwellings apply. In all cases the per-unit minimum is 800 square feet (§ 770-23B).

The calculation depends on the city's records and the specific comparison properties.