Ohio Rev. Code § 5545.05: Plans and specifications - where filed - alterations.

When approved by the commission provided for in section 5545.01 of the Revised Code, plans, drawings, profiles, bills of material, specifications of work, and estimates of cost thereof, shall be filed by the county auditor in his office, and shall not be altered, unless such alteration is first drawn, specified, and estimated as required for the original plans and approved by the commission. No such change shall be made until the price to be paid therefor has been agreed upon, in writing, between the commission and the contractor.