if the contractor shall fail to achieve completion of the works within the time prescribed in 4 （2） hereof， then the contractor shall pay to the employer at the rate of perday liquidated damages for such default and not as a penalty which shall elapse between the time prescribed by 4 （2）hereof and the date of certified completion of the works.the employer may， without prejudice to any other method of recov -ery， deduct the amount of such damages from any monies in his hands， due or which may become due to the contractor.the pay - merit or deuction of such damages shall not relieve contractor from his obligation to complete the works， or from any other of his obligations and liabilities under the contract.26 certification of completion of works
when the whole of the works have been substantially com - pleted and have satisfactorily passed any final test that may be prescribed by the contract， the contractor may give a notice to that effect to the employer accompanied by an undertaking to finish any outstanding work during the period of maintenance. such notice and undertaking shall be in writing and shall be deemed to be a request by the contract for issue of a certificate of completion in respect of the works.the employer shall ， with - in twenty - one days of the date of delivery of such notice either is - sue to the contractor a certificate of completion stating date on which， in his opinion， the works were substantially completed in accordance with the contract or give instructions in writing to the contractor specifying all the work which， in his opinion， re - quires to be done by the contractor before the issue of such cer - tificate.the employer shall also notify the contractor of any de -fects in the works affecting substantial . completion that may ap - pear after such instructions and before completion of the works specified therein .the contractor shall be entitled to receive such certificate of completion within twenty - one days of completion of the works specified and making good any defects so notified.
similarly， in accordance with the procedure set out in sub - （1）''of this clause， the contractor may request and the em - ployer shall issue a certificate of completion in respect of；
（a）any section of the permanent works in respect of which a separate time for completion is provided in the contract；and
（b）any substantial part of the permanent works which has been completed to the satisfaction of the employer.