Ohio Revised Code Title XXXV. Elections § 3503.04

Persons who are inmates of a public or private institution who are citizens of the United States and have resided in this state thirty days immediately preceding the election, and who are otherwise qualified as to age and residence within the county shall have their lawful residence in the county, city, village and township in which said institution is located provided, that the lawful residence of a qualified elector who is an inmate in such an institution for temporary treatment only, shall be the residence from which he entered such institution.