Da quello che ho letto, credo che sia questo ma non sono sicura.

Once works on site have been completed, the 12 months Defects Liability Period takes effect (6 months for very small projects). During this period, the contractor is responsible for attending to any defects which have become apparent, other than user-inflicted damage or wear and tear. The users may report such defects to the project officer via their School/Unit reporting officer. At the end of the Defects Liability Period, the project officer/architect and consultants will carry out an inspection to record defective or outstanding work which must be addressed.
Once outstanding defects have been attended to, the architect will issue the Certificate of Making Good Defects to the contractor, following which the remaining 2.5% retention monies are released. The Final Certificate for the contract is then issued.
http://www.st-andrews.ac.uk/estates/planningcompletion10.htm...

The issue of the certificate of ***making good defects*** in accordance
L'emissione del certificato di "riparazione dei difetti" secondo .......