Cal. Pub. Cont. Code § 10720

Before entering into any contract for a project, the trustees, pursuant to the powers invested in them by Chapter 8 (commencing with Section 66600) of Part 40 of Division 5 of Title 3 of the Education Code, shall cause to be prepared full, complete, and accurate plans and specifications and estimates of cost, giving such directions as will enable any competent mechanic or other builder to carry them out.