Should I have a written contract with a builder, and what goes in it?

Almost every dispute between a householder and a builder is a disagreement about what was agreed, not an allegation of dishonesty. Both sides remember the conversation accurately and differently. A written agreement is not an act of suspicion; it is the thing that lets both parties get on with the job without either of them having to remember.

Step by step

1. Attach the specification and the quote.The written scope you sent out and the priced quote that came back, both referred to as forming part of the agreement. This is the single most valuable part of the document.
2. State the price and what it excludes.The total, whether VAT is included, and an explicit list of exclusions. Exclusions written down are exclusions nobody argues about later.
3. Set out the programme.Start date, expected duration and any key dates. Domestic builders will not usually accept damages for delay, but a stated programme gives you something to refer to when it slips badly.
4. Set out the payment schedule against milestones.What is paid, when, and what physical progress triggers each payment. Tie payments to completed and inspectable work, never to dates alone.
5. Include a retention and say when it is released.A small agreed percentage held back after completion, released once the snagging list is cleared and any defects appearing in an agreed defects period have been put right. Say the percentage and the period in the document.
6. Set out how variations are agreed and priced.No extra work carried out without a written instruction, and no extra work priced after the event. This clause alone prevents most final-bill shocks.
7. Say who handles permissions and building control.Who applies, who pays the fee, who calls the inspections, and who is responsible for obtaining the completion certificate and scheme certificates.
8. Deal with insurance and site responsibility.Their public liability and, on a bigger job, contract works cover. Who is responsible for security of the site, protecting the rest of the house, and materials you supply.
9. Deal with subcontractors.That the main contractor remains responsible for subcontracted work, and that anyone doing gas, electrical or glazing work is appropriately registered and will provide certificates.
10. Say what happens at the end.Practical completion, the snagging process, the handover of certificates, warranties and manuals, and the defects period. A job with no defined end is a job that never quite ends.
11. Include a route for disagreement.A simple escalation: raise in writing, meet on site, then mediation or the trade body's dispute route before anything formal. Cheap to include, valuable if needed.
12. Consider a standard-form domestic contract for larger work.Published domestic building contracts written for homeowner projects exist and are inexpensive. On a project worth serious money, a standard form is better than anything either party drafts on the day.

Tips

• A reasonable builder will not object to a clear, fair written agreement. Strong resistance to putting anything in writing is itself a decision-quality piece of information.
• Keep the agreement short enough that both of you will actually read it. A two-page agreement that is used beats a twenty-page one that is filed.
• Record variations on the same email thread throughout, so the whole history of the job sits in one place in date order.

Common mistakes

• Relying on the quote alone as the contract — A quote prices work. It usually says nothing about programme, payment triggers, variations, insurance, certificates or what happens at the end — which is where disputes actually arise.
• Leaving the payment schedule to be agreed later — Once work has started your leverage falls with every payment. The schedule has to be agreed while you still have all of it.

Questions people ask