NEC ECC: Option C - Contractors Denies a Notified Defect is a Defect

I am the NEC Supervisor and during commissioning was offered to inspect the new installed ducting and ventilation system. I met with the contractor and during the inspection highlighted the site was still dusty and the ducting and ventilation were dirty. I requested evidence of cleaning. I believe it was cleaned but it was cleaned whilst the site was filled with dust and this was then pulled into the system making the cleaning pointless. The installation was not signed off. The Employer was under pressure to takeover the building /works. The contractor now states this is not a Defect.
I have responded.
I believe that under clause 20.1 of the NEC 3 ECC Option C contract the Works have not been provided in accordance with the Works Information. Therefore I am issuing this as a Defect under the Defined Terms Clause 11.2(5).

Therefore as per clause 10.1 in the spirit of mutual trust and cooperation I expect the Defect to stand until the evidence is provided.

Is this correct?

I suggest you identify in the notification of the Defect that part of the Works Information which has not been complied with, ie. the clause within the WI or referenced specifications/standards which covers cleanliness.

Even simpler here - you can give them an instruction to clean the site. They are obliged to follow that instruction (unless it is illegal or impossible). If they go on to notify that is a compensation event, you would reject it on the basis that it arises from their fault or is not one of the compensation events in 60.1.

It could have even been a reason not to certify Completion if it was that dirty that the Employer could not have put the works into use. That could have meant delay damages if they then exceed the Completion Date and also wont trigger the Defect Date (which is not in their interest to allow to happen)

Thank you very much. I have referenced HTM 03-01 part a which makes up part of the WI. I have also added a number of photos.

Hi Glenn, thank you for taking the time to respond. As we are a P22 contract. The Project Manager would issue the instruction. I’ll try and win on my own first and failing that casually drop this option to him.