Can my main contractor take delay damages without a non-completion certificate?

Under the JCT main contracts, the contract administrator issues a Non-Completion Certificate when the works miss their completion date. Without it, the client cannot take liquidated damages from your main contractor. A later extension of time cancels the certificate, and a new one is needed if the works are still late. The JCT subcontracts work differently. There is no certificate, but your main contractor must notify you that you have failed to complete in time. Bespoke subcontracts often copy the main contract wording, certificate and all. NEC subcontracts need neither: where they include delay damages, the damages run from the completion date. So read your own clause, and list every step it requires before a charge. That can mean a certificate or notice, a warning that damages may be taken, and a Pay Less Notice in time. Check each step was taken, in time and in the right form. A missing step can stop the deduction, even where the delay was yours. Whether a step is a strict condition is a question for your solicitor.