What Should a Builder's Contract Actually Include? A Plain-English Checklist

Your builder is about to start a £15,000 kitchen renovation. They have given you a price, talked through the plan, and suggested a start date. Before they begin, you should have a written contract. But what should actually be in it?

Most homeowners have never read a building contract. The ones available online are full of legal jargon or run to thirty pages. You do not need any of that. You need a clear, plain-English document that covers the things most likely to cause a dispute if they are not written down.

Here is the checklist. Each item exists because of real disputes that happened when it was missing.

1. Scope of work

What it is: A detailed description of exactly what the builder will do.

Why it matters: "Fit a new kitchen" means different things to different people. Does it include removing the old kitchen? Plastering? Decorating? Tiling? Flooring? If the scope is vague, you will disagree about what was included when the job is half done.

What to look for: The scope should list the work in enough detail that a third party could read it and understand what is being done. "Remove existing kitchen. Supply and fit new kitchen units per plan dated [date]. First and second fix plumbing. First and second fix electrics to new layout. Tiling to splashback area. Does not include flooring, decorating, or appliances." That level of detail prevents most scope arguments.

2. Price

What it is: The agreed price for the work, including whether it is a fixed quote or an estimate.

Why it matters: If the contract does not clearly state whether the price is fixed or approximate, you are relying on memory and goodwill — neither of which survives a dispute.

What to look for: A clear total price, whether it includes or excludes VAT, and whether it is a fixed quote (the builder is committed to this price) or an estimate (the final cost may vary). If it is an estimate, ask for a range and an upper limit.

3. Payment schedule

What it is: When and how much you pay at each stage of the project.

Why it matters: Paying everything upfront gives you no leverage if the work is not completed. Paying everything at the end leaves your builder financing the entire job. A staged payment schedule protects both sides.

What to look for: Payments tied to milestones, not dates. For example: 20% deposit on signing, 30% at first fix completion, 30% at second fix completion, 20% on final sign-off. The key is that you pay for work that has been done, not work that is about to be done.

4. Start and completion dates

What it is: When work begins and when it is expected to finish.

Why it matters: Without a completion date, a project can drift indefinitely. The builder takes on other work, your kitchen is half-finished for weeks, and there is no mechanism to hold anyone accountable.

What to look for: A specific start date and an expected completion date. A good contract also states what happens if the builder is late — not a financial penalty, but a requirement to notify you and provide a revised date. Delays happen; the contract should address how they are handled, not pretend they will not occur.

5. Variation process

What it is: How changes to the agreed scope are handled.

Why it matters: You will almost certainly want to change something during the project. A different tile. An extra socket. A wider doorway. Without a variation clause, these changes happen informally — and then appear as surprise charges on the final bill.

What to look for: A clause stating that any changes to the scope must be priced by the builder and approved by you in writing before the work is done. This protects you from being charged for things you did not agree to, and protects the builder from doing unpaid extras.

6. Defects and snagging

What it is: What happens when the work is finished but there are issues that need fixing.

Why it matters: Almost every project has a snagging list at the end — small issues that need putting right. Without a defects clause, there is no agreed process for reporting them, no timeline for fixing them, and no clarity on what you can withhold until they are resolved.

What to look for: A clause that gives you a defined period (typically 14-28 days after completion) to report defects. The builder should have a reasonable timeframe to fix them (typically 14 days). The contract should state what happens if they do not.

7. Retention

What it is: A small percentage of the total price held back until defects are resolved.

Why it matters: Retention gives the builder a financial incentive to come back and fix snagging items. Without it, once you have paid the full amount, you have no practical leverage to get defects resolved.

What to look for: A retention clause, typically 5-10% of the contract value, held for a defined period after completion (30-90 days). The money is released once all defects are resolved. This is standard practice in commercial construction and increasingly common in domestic work.

8. Insurance

What it is: Confirmation that the builder has public liability insurance and, if applicable, employer's liability insurance.

Why it matters: If a builder damages your property, injures someone, or causes damage to a neighbour's property during the work, their insurance covers it. Without insurance, you may end up paying for the damage yourself — or dealing with a builder who simply cannot afford to fix what they broke.

What to look for: A statement in the contract that the builder holds valid public liability insurance, with the policy number and insurer named. Ask to see the certificate if it is not referenced.

9. Dispute resolution

What it is: What happens if you and the builder disagree about something and cannot resolve it between yourselves.

Why it matters: Going straight to court is expensive and slow. A dispute resolution clause gives both sides a structured alternative — typically mediation or adjudication — that is faster and cheaper.

What to look for: A clause stating that disputes will first be addressed through negotiation, then mediation if needed, before either party resorts to legal action. This is not about avoiding accountability — it is about resolving disagreements quickly.

10. Termination

What it is: How either party can end the contract before the work is complete.

Why it matters: Sometimes things go wrong. The builder stops showing up. You lose confidence in the quality of work. Circumstances change. Without a termination clause, ending the contract is messy and ambiguous. With one, both sides know the process and consequences.

What to look for: Conditions under which either party can terminate, a notice period (typically 7-14 days), and what happens to payments already made and work already completed. The key is that termination is orderly, not chaotic.

Do you need all of this?

For a small job — a day's plastering, a tap replacement — a full contract with all ten clauses is overkill. A clear written quote with scope, price, and payment terms is usually sufficient.

For anything over a few thousand pounds, or anything lasting more than a week, you want most or all of these clauses. The bigger the job, the more important the contract becomes. An extension or full renovation without a proper contract is a gamble — and the stakes are your money, your home, and months of your time.

The good news: you do not need to write this yourself. A proper contract app generates a contract that covers all of these points from a short questionnaire. Your builder fills in the details, you review and sign, and both sides have a clear agreement before work starts.

For more on why written contracts matter even for smaller jobs, see our guide on whether builders need written contracts. And for a comparison of templates vs purpose-built contracts, see our guide on contract templates vs custom contracts.

The bottom line

A building contract does not need to be complicated. It needs to cover the things that cause disputes: scope, price, payments, changes, defects, and termination. If your builder sends you a contract that addresses all of these, it is a strong sign they take their business seriously — and that your project is in good hands. Every clause on this checklist exists to prevent a specific problem that has cost real people real money.

If your builder sends you a TradeContract, it already includes all of these clauses. If they do not use it yet — suggest it. It is free for you and takes them 5 minutes. Learn more.