Guide
When Building Work Goes Wrong: What to Do
A calm, practical guide to putting building problems right: what to do first, what the law expects, and where to go if talking doesn't resolve it.
The short version
When building work goes wrong, the first steps are the same. Record it, raise it in writing, and give the builder a fair chance to put it right.
Problems on building jobs are common and usually fixable. A leak after a roof repair, a finish that isn't what was agreed, a builder who has gone quiet or a job that has stalled halfway: each of these has a sensible first step, and in a great many cases that first step is enough. Good builders expect to come back and put things right, and the process for asking them to is straightforward.
What helps most is a calm order of doing things. Make sure nothing gets worse, write down what has happened, check what was agreed, and then tell the builder clearly, in writing, what you would like done and by when. Keeping a tidy record from the start makes every later step easier, whether the problem is sorted in a day or takes longer. Keeping evidence and records explains what is worth keeping.
This guide sets out that order, what consumer law says about building work in general terms, and the routes available if talking doesn't resolve it. For the letter itself, raising a complaint with a builder walks through what to include.
The process
Six steps that work for almost any problem
The order matters. Each step gives the next one something to stand on.
Make it safe and stop it getting worse
If water is coming in, cover it. If something is unsafe, keep people away from it. Reasonable steps to limit further damage are expected of you, and they protect your home. Keep receipts for anything you spend.
Record what you can see
Take dated photographs and short videos, and write a note of when you first noticed the problem and what has happened since. Record it before anyone starts fixing it.
Check what was agreed
Get out the quote, the contract, any written changes and the warranty terms. The question is whether the work matches what was agreed and whether it was done to a proper standard.
Tell the builder in writing
A phone call is a good start, but follow it with an email or letter setting out the problem, what you would like done and a reasonable date for a response. Keep a copy.
Give them a fair chance to put it right
Agree a date for a visit and let them do the work. Consumer law generally expects the builder to be given the opportunity to fix their own work before anything else happens.
Escalate in stages if nothing happens
A formal letter, then independent advice, dispute resolution or, as a last resort, a court claim. Many problems never get this far.
Your rights in plain terms
What the law expects from building work
When you hire a business as a private individual, the main law is the Consumer Rights Act 2015. When a business carries out work for a consumer, the Act says the work must be done with reasonable care and skill. Where the price or the timing was not fixed in advance, it should be a reasonable price and done within a reasonable time. Things the builder told you about the work, in writing or in conversation, can also count as part of the agreement if you relied on them when deciding to go ahead.
Materials supplied as part of the job are covered too. In general terms, they should be of satisfactory quality, fit for purpose and as described.
When work falls short, the law looks first to the builder putting it right. You can ask them to redo or repair the work, at their cost, within a reasonable time and without causing you significant inconvenience. If that isn't possible, or doesn't happen within a reasonable time, you may be entitled to a price reduction, which in some cases can be a refund of what you paid. Consumer rights for building work explains each of these in more detail.
Your written contract or quote sits alongside these rights. It can add to them, for example with a longer warranty, but a business generally cannot use its terms to take away your basic statutory rights as a consumer. There are also time limits for making a claim, and they differ between the nations of the UK, so if a problem has been left for a long time, check the current position with Citizens Advice. How long do I have to complain? covers this in general terms.
This is general information, not legal advice. Citizens Advice and GOV.UK publish free, current guidance on your consumer rights. If a large sum is involved or the builder disputes the problem, a solicitor can advise on your particular situation.
Where to start
Six common problems, each with its own first move
Working out which kind of problem you have makes the conversation with the builder much easier.
Work that isn't right
Leaks, cracks, poor finishes or work that doesn't match the quote. The builder should put defective work right. Dealing with defective workmanship sets out how to ask.
A builder who has gone quiet
Often busy rather than absent, but worth handling in a clear order. When a builder stops responding covers the steps.
A job left unfinished
A pause is not always abandonment. Abandoned building jobs explains how to tell the difference and what to do if it is.
A business that has stopped trading
Companies House shows whether a company has entered insolvency. When a contractor goes out of business explains what happens next.
Damage to your property
Accidental damage caused by the builder is usually a matter for their public liability insurance. What if the builder damaged my property? covers it.
Loose ends at the finish
Small unfinished items and touch-ups are snags, not disputes. Snagging after completion shows how to list and resolve them.
Evidence
Good records make every problem easier to solve
You will probably never need to prove anything to anyone. Keeping records is still worth the few minutes it takes, because it keeps the conversation with the builder about facts, and because it makes every later step, from a warranty claim to mediation, far simpler if it comes to that.
The core file is short: the quote or contract, any written changes to the work, the warranty terms, receipts for every payment and the builder's full name and contact details. Add to it as the job goes on. Dated photographs of the work at each stage are especially useful, as is a simple log of calls, visits and messages with the date and a line on what was said.
When a problem appears, photograph it before anything is touched, from a distance and close up, and keep taking photographs if it changes. After heavy rain, for example, a photograph of a damp patch with the date on it is worth more than a description written weeks later. What records should I keep during building work? has a full list, and how do I prove work was defective? covers independent reports.
If you paid by bank transfer or debit card, your bank statement already records who you paid and when. Keep any receipts or invoices alongside it.
Raising it
Raising a problem so it gets fixed quickly
The way a problem is raised often decides how quickly it is fixed. A calm, specific message sent once is easy to act on. A run of phone calls, each adding something new, is harder for a busy builder to keep track of and easier to dispute later.
A good first message covers five things: what the problem is, where it is, when you noticed it, what you would like done, and a reasonable date by which you would like a reply or a visit. Attach photographs. Refer to the quote where it helps. Keep the tone factual rather than angry, even if you are frustrated, because the message may be read by other people later.
If you can, meet the builder on site and look at the problem together. Many issues turn out to be quick fixes once both of you are standing in front of the same thing. Confirm what was agreed in a short message afterwards. If you need a short version to send today, how do I complain about a builder? gives one.
Keeping it on track
What helps a resolution, and what tends to slow it down
None of the right-hand points is a disaster. Each one simply makes the problem harder to put right.
Helps
- Raising the problem as soon as you notice it
- One clear written message with photographs
- A realistic date for a reply or a visit
- Letting the builder inspect and fix their own work
- Holding back only an amount in proportion to the problem
- Confirming every agreement in writing
Slows it down
- Waiting months before mentioning it
- Several calls, each with a new complaint
- Deadlines that no builder could meet
- Having someone else fix it before the builder has seen it
- Withholding the whole balance over a small snag
- Posting accusations online while it is being sorted
Delays, prices and damage
Problems that aren't about the quality of the work
Not every problem is a defect. Three others come up often enough to deserve a word of their own, and each has a sensible first step.
Work running late. Start with what was agreed. If the quote or contract gave a start or finish date, the builder should keep to it or explain why they can't. If no date was agreed, the law generally expects the work to be done within a reasonable time for a job of that kind. Weather, a delayed delivery or a problem uncovered once work starts can all justify some delay. What you are entitled to is an explanation and a realistic revised date, so ask for both in writing. If the delay is causing you costs, such as extra accommodation or storage, say so at the time and keep the receipts.
The price going up. Compare the request with the written quote. Extra work you asked for, or agreed in writing, is normally extra cost. A provisional sum in the quote may also change once the real figure is known. A rise that has not been explained or agreed is worth questioning before you pay it. Ask for a written breakdown and a reason, and do not agree to further work until the price is settled.
Damage to your home. If the builder damages part of your home or your belongings while working, photograph it and tell them in writing straight away. Accidental damage of this kind is what a builder's public liability insurance is for, so ask them to notify their insurer. It is also worth telling your own home insurer, who can advise on what your policy covers.
Warranties
Using a workmanship warranty
A workmanship warranty is the builder's own promise to put right defects in their work that appear within a set period. It sits on top of your consumer rights rather than replacing them. The terms should be in writing: how long it lasts, when it starts, what it covers and what it excludes. Many warranties start from completion, so it is worth knowing that date.
A warranty usually covers faults in how the work was done. It generally does not cover damage caused later by something else, such as a storm, a knock or a lack of maintenance, and it may treat materials differently from labour, since materials often come with the manufacturer's own guarantee. Workmanship warranties explained goes through the detail, and how long does a workmanship warranty last? gives the short answer.
To use it, contact the builder in writing, describe the problem, attach photographs and refer to the warranty. Treat it like any other request to put work right: a clear message, a reasonable date, and a record of what happens.
A warranty given by a business depends on that business continuing to trade. Some warranties are backed by insurance, which can continue if the firm stops trading. It is worth knowing which kind you have before you need it.
Money
Paying fairly while a problem is sorted out
Money is where disagreements tend to harden, so it is worth being careful. If the job is not finished or a clear defect is outstanding when the balance falls due, it is common to agree with the builder that part of the payment waits until the work is put right. Agreeing this openly, in writing, is far better than simply not paying.
If you do hold money back, keep the amount in proportion to the problem, tell the builder in writing what you are holding and why, and pay the rest as agreed. Holding back far more than the problem is worth can itself put you in breach of the contract and makes a dispute more likely. When to withhold payment sets out the principles.
On larger projects, some contracts build this in from the start with a retention, a small part of the price held back for an agreed period after completion. Retention on building work explains how that works, and final payment and snagging covers the end of a job more generally.
Avoid paying extra money to get a builder to return and fix work that was already paid for. If the builder asks for more to put right their own defect, ask for the reason in writing.
If talking doesn't resolve it
The routes available, in the usual order
Each step is more formal than the last. Take them in order and give each one time to work.
A formal letter
Set out the problem, what you have already asked for, what you now want done and a final date. Say what you will do if nothing happens. Courts generally expect this kind of letter before any claim is made.
An independent opinion
Where the builder disputes the problem, a report from an independent surveyor or specialist can settle what is wrong and what it will cost to fix. What if the contractor disputes the problem? covers this.
Help from a scheme or trade body
If the builder belongs to a trade association or scheme, it may run a complaints process or offer dispute resolution. Check the scheme's own website.
Mediation or other dispute resolution
An independent person helps both sides reach an agreement without going to court. Mediation and ADR for building disputes explains the options.
Advice and reporting
Citizens Advice can advise on your rights and, where appropriate, pass details to Trading Standards. In Scotland, Advice Direct Scotland provides this service, and in Northern Ireland, Consumerline.
A small claim, as a last resort
The courts have a simpler procedure for lower-value claims, which you can often start online. Small claims for building work explains what is involved.
Formal routes
Dispute resolution and the courts, in brief
Alternative dispute resolution, or ADR, covers ways of settling a disagreement without a court hearing. Mediation is a common choice for domestic building work: a trained mediator talks to both sides and helps them agree a way forward. It is voluntary, usually quicker and cheaper than court, and whatever is agreed can be written up so both sides are bound by it. Some trade schemes offer their own conciliation or adjudication services to customers of their members.
The small claims process exists so that people can bring lower-value claims without a solicitor. There is an upper limit on the amount you can claim this way, and it differs between England and Wales, Scotland and Northern Ireland. There are court fees, and you would need to show what went wrong and what it cost you, which is where your records matter. GOV.UK sets out the current process and fees for England and Wales, and the Scottish and Northern Ireland courts publish their own.
Before starting any claim, it helps to ask a practical question as well as a legal one: if you won, could the builder pay? A claim against a business that has stopped trading may not be worth the fee. Can I take a builder to small claims? covers this, and when should I get legal advice? explains when a solicitor is worth the cost.
Getting it fixed
Bringing in another builder, at the right time
Sometimes the original builder cannot or will not put things right, and another builder has to. The timing matters. Generally the original builder should be given a fair chance first, with the problem recorded before anyone else touches it, because having the work redone early can make it harder to recover the cost later. In an emergency, do what is needed to stop further damage and keep the evidence. When you do bring someone in, ask for a written assessment and quote for the remedial work, and expect them to warrant their own work rather than the earlier builder's.
When the builder is no longer trading
Checking where you stand if a business has closed
If a limited company stops trading, its record on the free Companies House register usually shows it: a company in liquidation or administration will say so, and notices about insolvency are published in The Gazette, the official public record. The insolvency practitioner handling the company is named, and they are the person to contact about money you are owed.
In that situation you are usually an unsecured creditor, which in practice means you may recover little or nothing of what you are owed. A warranty given by the company generally ends with it, unless it was backed by insurance. It is still worth registering your claim, and it is worth checking whether any part of the work carried its own manufacturer's guarantee.
A sole trader is not a company, so there is no Companies House record to check. Here the individual remains personally responsible for their business debts, although whether pursuing them is practical is a separate question. What if my builder goes bust? gives the short answer.
Next time
Setting up a job so problems are easier to solve
Nothing prevents every problem, but a few habits at the start make any problem far easier to deal with. A written quote that sets out the work, the materials, the price and the payment terms gives everyone the same reference point. So do written warranty terms, a clear start date and an idea of how long the work should take.
Knowing who your contract is with matters too, especially where more than one company is involved. What a main contractor is responsible for explains why, and what paperwork should I get before work starts? lists the documents worth having in hand.
During the job, agree any changes in writing before they happen, with any change to the price. Pay in stages that follow the work rather than run ahead of it. And raise small concerns early, while they are small. Preventing problems before they start covers this in full.
Where Mortaro fits
Chasing and escalation, handled for you
Mortaro coordinates domestic building projects. We appoint a contractor from our network, prepare the written quotation and handle the communication throughout. If something needs putting right, you tell us and we take it up with your contractor, push for a visit and a resolution, and keep you updated rather than leaving you to chase. How escalation works with a coordinator explains the arrangement in general terms.
Your construction contract is with your contractor, who is named in your quotation. They provide the workmanship warranty, a minimum of 12 months across our network and usually from completion, so the contractual remedy for defective work is against them. We do not guarantee or indemnify the work. What we do is escalate, and contractors who fail to meet our standards are removed from the network. Putting things right sets out our process.
Straight answers
Common questions when building work goes wrong
What is the first thing I should do?
Make sure nothing gets worse, photograph the problem, then tell the builder in writing what is wrong and what you would like done, with a reasonable date for a reply. That is the right start for almost any problem.
Is my builder responsible for defects?
In general, yes, for defects in their own work and in the work of anyone they bring in. The law expects work to be done with reasonable care and skill, and the first remedy is for the builder to put it right, at their own cost.
Should I get another builder to fix it straight away?
Usually not, unless it is an emergency. Give the original builder a fair chance to put it right first, and record the problem before anyone else touches it. Otherwise it can be harder to recover the cost later. Getting remedial work done explains when and how to bring someone else in.
Can I stop paying the builder?
You can discuss holding back an amount in proportion to an outstanding problem, but withholding everything is rarely fair and can put you in the wrong. Agree it in writing where you can.
Who can help me for free?
Citizens Advice gives free guidance on consumer rights and runs a consumer helpline. In Scotland, Advice Direct Scotland does the same, and in Northern Ireland, Consumerline. If the builder belongs to a trade scheme, the scheme may also help.
When do I need a solicitor?
When a large sum is involved, when the builder disputes the problem and talking has stopped, or before you end a contract or start a claim. Many solicitors offer a short initial consultation.
Side by side
Common problems, the first step, and where to go next
Start in the middle column. Often, that is where it ends.
| The problem | The first step | If it isn't resolved |
|---|---|---|
| Work that is faulty or poorly finished | Record it, then ask the builder in writing to put it right by a reasonable date | A formal letter, then an independent report, then dispute resolution |
| The builder has stopped replying | Try every contact route, then write with a clear date for a reply | Check the company's status, then decide whether the job has been abandoned |
| The job has been left unfinished | Make the site safe and weatherproof, then write asking the builder to return by a set date | Advice on ending the contract and arranging completion by someone else |
| Damage to your home or belongings | Photograph it and tell the builder in writing | The builder's public liability insurer, and your own home insurer |
| The work is running late | Check the agreed dates, then ask in writing for a revised programme | A formal letter setting out the delay and its effect on you |
| The price has gone up | Compare the request with the written quote and any agreed changes | Ask for the extra cost to be explained and agreed in writing before paying |
| The builder has gone out of business | Check the company's status on Companies House | The insolvency practitioner, and a new builder to assess the work |
| You disagree about whether it is a defect | Put the disagreement in writing and suggest a joint site visit | An independent expert opinion, then mediation or another form of dispute resolution |
This is general information, not legal advice. Citizens Advice and GOV.UK publish free, current guidance on consumer rights, dispute resolution and the small claims process.
Go deeper
Guides in this section
Abandoned Building Jobs: What to Do If Your Builder Walks Off
How to tell whether a job has really been abandoned, protect your home, and arrange for the work to be finished without making things harder for yourself.
ReadConsumer Rights for Building Work: A Plain Guide
What the law expects of a builder, what you can ask for if the work falls short, and where the law is less helpful than people expect.
ReadDealing with Defective Workmanship: A Homeowner’s Guide
How to recognise defective workmanship, ask the builder to put it right, and move things forward calmly if they don't.
ReadGetting Remedial Work Done: Putting Faulty Building Work Right
The order of events for putting defective work right, when to bring in someone new, and how to approach the cost.
ReadHow Escalation Works When a Coordinator Runs Your Project
What a project coordinator can do when something goes wrong, what stays with the contractor, and exactly how Mortaro escalates on your behalf.
ReadHow to Raise a Complaint with a Builder and Get It Resolved
How to raise a problem with a builder so it gets put right, and where to turn if they will not engage.
ReadKeeping Evidence and Records During Building Work
What to keep, how to photograph a problem so the picture is useful, and how to build a record that settles questions quickly.
ReadMediation and ADR for Building Disputes
The ways to settle a disagreement with a builder without going to court, how mediation works in practice, and how to tell whether it suits your dispute.
ReadPreventing Problems With Building Work Before They Start
Most building disputes trace back to something that could have been settled at the start. The checks, paperwork and habits that keep a job on track.
ReadSmall Claims for Building Work: A Homeowner’s Guide
How the small claims process works for a dispute over building work, what to do before you claim, and the questions worth answering before you start.
ReadSnagging After Completion: Defects That Show Up Later
What to do when problems appear weeks or months after the builder has left: how to tell a defect from wear, when to check, and how to report it under the warranty.
ReadWhen a Builder Stops Responding: What to Do
A builder going quiet is common and often has an ordinary explanation. Here is how to get a reply, and what to do if one doesn't come.
ReadWhen a Contractor Goes Out of Business: What to Do Next
How to confirm what has happened, look after the work, deal with money already paid and get the job finished or put right.
ReadWhen to Withhold Payment From a Builder
When holding back part of a payment is fair, how to keep the amount proportionate, and the risks worth weighing before you do it.
ReadWorkmanship Warranties Explained: What They Cover and How to Use One
What a builder's workmanship warranty usually covers, when the clock starts, how it fits with your legal rights, and how to make a claim.
ReadQuick answers
Common questions
Get in touch
Tell us about your project
Tell us what you need doing and where. There is no charge for a quotation and no obligation to proceed.