Whether you use a JCT form or the builder’s own paperwork, the test is the same: does the document answer the twelve questions below? Run any contract you’re offered against this list before signing — each gap is a future argument with your name on it.
1. Who, exactly, are the parties?
The builder’s limited company name and company number, not just a trading name — you need to know who you’d actually sue, and who carries the insurance. If it’s a sole trader, their full name and address. Check the company is active on Companies House and hasn’t been incorporated three weeks ago.
2. What is the scope?
The work described by reference to attached documents — drawings, a specification, a room-by-room list. The words “as per quote” only work if the quote itself is detailed and attached. Anything excluded should say so explicitly (“no decoration; skip and scaffold by client”).
3. What is the price — and what isn’t fixed?
The contract sum, VAT position stated, and provisional sums for anything undesigned, each with a stated allowance. A “fixed price” with silent gaps is a variations machine.
4. How is payment structured?
Stage payments tied to completed milestones, never calendar dates, sized so you’re always paying in arrears. State what evidence accompanies each request (photos, a walk-round) and your payment terms (7 days is fair).
5. Deposit — and its protection
If there’s a deposit at all, state what it covers and when it’s earned. On materials-heavy jobs, ask for it to be held against named orders.
6. When does it start and finish?
A start date, a completion date or duration, and the grounds on which the date moves (weather, your changes, genuinely unforeseen work — each notified in writing at the time, not claimed retrospectively at the end). Larger jobs should carry liquidated damages: a stated weekly sum deductible for unexcused overrun.
7. How are changes handled?
The single most valuable clause: no variation without a written price and time impact agreed before the work is done. Email is fine. This one sentence prevents the classic end-of-job extras stack.
8. Who insures what?
The builder’s public liability insurance (£2m–£5m typical) with insurer and expiry stated — and ask to see the certificate. Confirm who covers materials on site and works in progress, and notify your own home insurer that works are happening (many policies require it).
9. Site practicalities
Working hours, toilet access, storage, parking, protection of finished areas, waste removal and who pays for the skip. Thirty seconds each to agree now; daily friction if not.
10. Defects period and retention
A stated period after completion (three to twelve months) during which notified defects are fixed free, and a retention — 2.5–5% held until snagging is complete, half typically released at completion and half at the end of the defects period.
11. Termination
The grounds on which either side can end the contract (persistent non-payment; abandonment, persistent defective work, insolvency), the notice required, and how work done is valued at that point. You will probably never use it — but its absence is what makes walking-off disputes so messy.
12. Disputes
An escalation clause: good-faith discussion, then mediation or adjudication, court last. Cheap to include, and it keeps a £3,000 disagreement from becoming a £30,000 one — the full route is in our disputes pillar.
Using the checklist
Score whatever you’ve been handed out of twelve. A professional outfit’s paperwork typically covers nine or ten of these; a JCT Home Owner or Minor Works form covers all twelve for £20–£50. If the builder’s own terms fail more than a couple, propose the JCT form — a fair builder has no reason to refuse a contract drafted to be neutral.
This guide is general information for homeowners in England and Wales, not legal advice.
