What is a contra-charge or back-charge in construction?

Common ones are damage, cleaning, delay, attendances not provided, defects put right by someone else and plant hire. The standard forms do not use the term. It is set-off by another name: a sum your main contractor says you owe, taken out of what it owes you. Three things decide whether it sticks. First, your subcontract must allow the deduction, and many subcontracts widen that right well beyond the standard form. Second, the deduction must come through the payment notices, under section 111 of the Housing Grants, Construction and Regeneration Act 1996. A contra-charge in a Pay Less Notice, with a sum and a basis, is procedurally sound. One that first appears in a final account assessment with neither is not. Third, the sum must be backed by evidence, just as a claim would be. That means what happened, when, who recorded it, what it cost and how the figure was worked out. So when a contra-charge lands, test it on all three. The one most often dropped is the charge raised months after the event, with no record made at the time and a round figure.