Most homeowners sign a building contract having read the price and the start date closely and skimmed everything else. The clauses that actually protect you if something goes wrong are usually the ones given the least attention.
A short, deliberate check of a handful of specific points before signing catches the majority of problems that otherwise only surface once work is underway and leverage has shifted.
What actually triggers each payment
Check precisely what has to happen before each stage payment is due — is it a date, a percentage estimate, or a defined, verifiable milestone such as 'roof structure complete and watertight'? Vague triggers are the most common source of payment disputes.
If a payment stage is worded ambiguously, ask for it to be rewritten against something you or an independent person could reasonably verify by looking at the building, not by taking the builder's word for progress.
How variations are priced and agreed
Confirm the contract actually requires variations to be priced and accepted in writing before work proceeds, not just 'agreed' in some unspecified way. Check whether there's a stated maximum the contractor can proceed on without your written sign-off, since some contracts allow small variations to proceed automatically.
If the variation clause is silent on how disputes about a variation's price get resolved, that's worth raising before signing rather than discovering it mid-dispute.
What happens if either side wants to end the contract early
Check the termination clause: what notice is required, what happens to materials already ordered or delivered, and how work completed to date gets valued and paid for. A contract silent on this leaves both sides guessing if the relationship breaks down.
This clause matters even if you never expect to need it — its main value is making clear, calm negotiation possible if a serious disagreement does arise, rather than an argument with no agreed process.
Defects period and what it actually covers
Check how long the defects period runs, what it covers (workmanship generally, rather than normal wear or client-supplied materials), and what the process is for reporting and resolving a defect within it. A defects period with no clear reporting process is hard to rely on when something does go wrong.
Also check whether retention, if used, is genuinely tied to the defects period closing, rather than to a fixed date that might arrive before snagging is actually finished.
Insurance and who is covered for what
Confirm the contract states which insurances are in place — public liability, and where relevant, works or contract insurance covering the building itself while work is ongoing — and who is responsible for what during the works. This matters particularly on a renovation of an occupied, insured house, where two insurance policies can otherwise leave gaps between them.
Ask to see evidence of current cover rather than relying on the contract's statement alone, particularly on a larger project where the financial exposure of a gap is significant.
Common questions
Can I negotiate contract terms, or is it take-it-or-leave-it?+
Most reasonable contractors will discuss and clarify contract terms before signing, particularly around payment triggers and variation processes. A refusal to discuss or clarify any term is itself worth treating as information.
What if the contract doesn't mention a defects period at all?+
Ask for one to be added. A defects period, typically a set number of months after completion during which workmanship issues are put right at no extra cost, is standard practice and its absence should be queried rather than assumed to be an oversight.
Should I get a solicitor to review the contract?+
For a larger renovation or extension, a brief solicitor review of the contract terms is a reasonable and proportionate cost. For very small jobs it's less commonly done, but the same checklist of clauses still applies.
Talk through our contract terms before you sign
We'll explain payment triggers, variation terms and the defects period in plain English before you commit to anything.