Ohio Rev. Code Ann. § 5517.02
(B)
(1) After complying with division (A) of this section, the director may proceed without competitive bidding with maintenance or repair work by employing labor, purchasing materials, and furnishing equipment, if the total estimated cost of the completed operation, or series of connected operations, does not exceed the following, as adjusted under division (B)(2) of this section:
(E) The director shall proceed by competitive bidding to let work to the lowest competent and responsible bidder after advertisement as provided in section 5525.01 of the Revised Code in both of the following situations: