Toledo, OH Accessory Structures: ADU Rules (2026)

Toledo added accessory dwelling unit standards to its Zoning Code at Section 1105.0207 by Ordinance 440-25, passed September 23, 2025. Under subsection A, an ADU may be established within an existing single-family building or as a detached structure on the same lot, and no more than one ADU is permitted per lot. Subsection C requires each ADU to have a separate exterior entrance independent of the entrance to the principal dwelling. Subsection D requires the lot to meet the minimum lot size for single-family dwellings in its zoning district, and subsection E caps the ADU's footprint at 60 percent of the primary dwelling's footprint, with the ADU also counting toward the 30 percent rear-yard accessory-building coverage cap in Section 1105.0204(A).

Setbacks under subsection G vary by scenario: an ADU built inside the envelope of an existing house is exempt from setbacks if it doesn't expand the footprint, a detached ADU must meet the standard accessory-building setbacks in Section 1105.0201, and an ADU added onto the house must meet the principal-dwelling setbacks for its zoning district. Height is capped at the accessory-building limit in Section 1105.0202, or the height of the existing principal structure for detached units. Subsection I requires detached ADUs to be permanent construction with permanent utility hookups, subsection J exempts ADUs from off-street parking requirements in Section 1107.0300, and subsection L bars mobile homes, recreational vehicles, travel trailers, or other wheeled structures from serving as ADUs.