How to handle a dispute with your builder

Handle a builder dispute by raising the problem early and specifically, putting it in writing, documenting the work with photographs, and keeping unpaid money aligned with unfinished work. Escalate through a formal complaint and alternative dispute resolution before considering court, which is the slowest and most expensive room in the building.

Disputes are common enough to plan for.

Citizens Advice logged 36,534 complaints about home maintenance and improvement work in a single year to June 2025, more than 700 every week, with major renovations among the top categories [1].

Most of those disputes follow the same arc. And most are winnable, or avoidable entirely, if you handle the first fortnight well.

Here's the sequence, step by step.

What are the most common builder disputes?

The most common builder disputes involve quality of finished work, costs rising beyond what was agreed, timelines slipping without explanation, and jobs left unfinished. In the Citizens Advice data, low-quality service alone accounted for 19,281 complaints, over half the annual total.

It's worth naming what usually sits underneath: ambiguity.

Work that was never specified in writing, changes agreed on the stairs, payments that ran ahead of progress. Disputes are rarely born the day the argument starts. They're born weeks earlier, in the gap between what two people each assumed.

What should you do first when something goes wrong?

Raise the problem with your builder directly, early, and in specifics: what's wrong, where, and what you'd like done about it. Most builders would rather fix a tiling issue in week two than read about it in a solicitor's letter in week ten.

Talk first. Then confirm in writing the same day.

A short, calm email ("as discussed this morning, the shower tray isn't level and we've agreed it'll be re-set before tiling continues") does two jobs: it keeps things human and starts the paper trail.

Tone matters more than people expect. The relationship usually survives a defect. It rarely survives an ambush. You're aiming for the register of a colleague flagging a problem, not a prosecutor opening a case, because nine times out of ten this person is still finishing your house.

A surprising number of disputes never need to exist at all, which is why our guide on how to work well with your builder is quietly the best dispute-resolution article we've written: weekly check-ins and clear decisions prevent what formal letters can only tidy up.

How do you document a dispute properly?

Document a dispute with dated photographs of the work, copies of the contract and quote, every relevant message and invoice, and a written record of what was agreed verbally and when. Evidence gathered while things are civil is worth ten times evidence reconstructed after they aren't.

Pay special attention to changes.

Mid-project alterations agreed in a doorway are where costs and expectations drift apart fastest, and they're precisely why written change orders exist. If you're unsure what one looks like, our explainer on what a change order is covers how each change gets priced, agreed and recorded before it becomes work, so neither side is negotiating from memory later.

If the dispute is about workmanship quality and the sums are serious, an independent report changes everything. A surveyor or relevant specialist will inspect and write up defects for a few hundred pounds, and their letterhead does what your photographs can't: it turns "I think this is wrong" into "a professional says this is wrong". Builders settle quickly against reports.

When should you withhold payment, and when shouldn't you?

Withhold payment only for work that's genuinely incomplete or defective, and in proportion to the problem. Unpaid money tied to unfinished work is legitimate leverage. Refusing to pay for completed stages because of a dispute elsewhere turns your strongest position into their best argument.

The law backs the reasonable version of this.

Under the Consumer Rights Act 2015, building work must be carried out with reasonable care and skill, and you're entitled to have substandard work repeated or remedied. But the Act protects proportionate responses, and a payment strike on everything, everywhere, all at once reads very differently in front of a judge.

How much is proportionate? The practical answer is the cost to remedy: get a price for fixing the specific problem, and hold roughly that. It's defensible, it's explainable in one sentence, and it leaves the rest of the relationship intact.

This is also the strongest argument for milestone payments generally: they build proportionality in from day one, so the leverage exists without you having to manufacture it mid-argument. 

How do you escalate if you can't agree?

Escalate in steps: a formal written complaint with a deadline for response, then alternative dispute resolution such as mediation or an ombudsman scheme if the builder belongs to one, then Trading Standards via Citizens Advice for serious cases, with court as the final step rather than the third one.

The formal letter matters because it changes the register.

Structure it in five short parts: the facts with dates, the specific defects or breaches, the evidence you hold, the remedy you want, and a reasonable deadline, usually 14 days, with a plain statement of what happens next if it passes. Many disputes end here, because a documented complaint signals you'll follow through.

ADR is cheaper and faster than legal action, and courts expect you to have tried it. Check whether your builder belongs to a trade body with a dispute scheme, because membership usually binds them to use it.

Court is the backstop, not the plan. Small claims handles disputes up to £10,000 in England and Wales without needing a solicitor, fees scale with the claim size, and contract claims carry a six-year limitation period, so you're not racing a clock. But even winning costs months, and enforcement of a judgment against a reluctant builder is its own second project. Exhaust the cheaper rooms first.

How do disputes work on a Beams project?

Beams projects are structured so disputes start small and stay resolvable. Your construction money is held securely and only releases when you approve each milestone, so the leverage is built in rather than argued for. When your builder marks a stage complete, you get the evidence in your dashboard and seven days to review it. If the work is right, you approve it and the payment is released. If it isn't, you reject it with a note that goes straight to the builder to put right, and nothing moves. The one thing to know is that the seven days is a deadline, not a pause: leave it untouched and the milestone auto-approves and pays out, so the window is there to be used.

Picture the classic case: a bathroom renovation where the shower leaks at the final walkthrough.

On an unprotected project, that's a cheque already cashed and a phone that rings out. On a Beams project it's a Sign Off milestone you haven't approved, a snagging list still open, and the final payment still held, so the reason to come back and fix it stays fully intact. Behind that sits a 12-month workmanship warranty from sign-off: report a defect inside that window and your builder is responsible for returning to remedy it, with Beams on hand to make sure it happens. And if your builder leaves the network or stops trading during those 12 months, Beams steps in with up to £10,000 of cover.

Who handles what is worth understanding before you ever need it. Our guide to who's responsible for what on a Beams project maps it out plainly, and the protections on every project set out the contract, payment and warranty safeguards in one place.

The best dispute is the one that never escalates. The structure decides that long before the tiling does.

Sources

[1] Citizens Advice press release (data period July 2024 – June 2025) – 36,534 complaints about home maintenance and improvements (700+ per week); 19,281 concerned low-quality service; major renovations including lofts, conversions and extensions accounted for 4,365 complaints. https://www.citizensadvice.org.uk/about-us/media-centre/press-releases/shoddy-tradeswork-is-sparking-more-than-700-complaints-a-week-says-citizens/