(65 ILCS 5/4-5-11) (from Ch. 24, par. 4-5-11)
    Sec. 4-5-11. Except as otherwise provided, all contracts, of whatever character, pertaining to public improvement, or to the maintenance of the public property of a municipality involving an outlay of $10,000 or more, shall be based upon specifications to be approved by the council. Any work or other public improvement which is not to be paid for in whole or in part by special assessment or special taxation, when the expense thereof will exceed $25,000, shall be constructed as follows:
        (1) By a contract let to the lowest responsible
    
bidder after advertising for bids, in the manner prescribed by ordinance, except that any such contract may be entered into by the proper officers without advertising for bids, if authorized by a vote of 4 of the 5 council members elected; or
        (2) In the following manner, if authorized by a vote
    
of 4 of the 5 council members elected: the commissioner of public works or other proper officers to be designated by ordinance, shall superintend and cause to be carried out the construction of the work or other public improvement and shall employ exclusively for the performance of all manual labor thereon, laborers and artisans whom the city or village shall pay by the day or hour, but all material of the value of $25,000 and upward used in the construction of the work or other public improvement, shall be purchased by contract let to the lowest responsible bidder in the manner to be prescribed by ordinance.
    Nothing contained in this Section shall apply to any contract by a municipality with the United States of America or any agency thereof.
(Source: P.A. 100-338, eff. 8-25-17.)