Ohio Revised Code Title I. State Government § 153.50

(A) As used in sections 153.50 to 153.52 of the Revised Code:

(B) Except for contracts made with a construction manager at risk, with a design-build firm, or with a general contracting firm, an officer, board, or other authority of the state, a county, township, municipal corporation, or school district, or of any public institution belonging thereto, authorized to contract for the erection, repair, alteration, or rebuilding of a public building, institution, bridge, culvert, or improvement and required by law to advertise and receive bids for furnishing of materials and doing the work necessary for the erection thereof, shall require separate and distinct bids to be made for furnishing such materials or doing such work, or both, in their discretion, for each of the following branches or classes of work to be performed, and all work kindred thereto, entering into the improvement: