What should be in a building contract?
A defined scope with drawings and specification, a fixed price or clear pricing basis, start and completion dates, staged payments tied to certified progress, a retention held after completion, a written variations process, and a defects liability period. If any are missing, the contract protects the builder more than you.
The scope is the foundation of everything. It should reference specific drawings and a written specification listing materials and finishes, so that 'what was agreed' is a document rather than a memory. Most disputes we hear about are not really about money — they are about two people having different recollections of what was included, which a written scope prevents.
Payments should be tied to completed and inspected stages, never to dates in the calendar. A builder paid on the 1st of the month regardless of progress has no incentive to keep pace. Payment on completion of strip-out, structure, first fix, plastering, second fix and handover keeps the money aligned with the work. A retention of around 5 percent held for six months after completion gives you leverage to get defects fixed.
For anything above roughly £50,000, use a standard form contract — a JCT Homeowner or Minor Works contract — rather than a builder's own terms. They are written to be even-handed, they include a proper variations mechanism and a defects liability period, and they are understood by everyone. A builder who resists using one is telling you something worth listening to.
More on this in living through the works, or see all 42 questions.
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