Dealing 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.
The short version
Defective work is the builder's to put right. Your job is to record it clearly and ask them to fix it.
Defective workmanship means work that has not been done to a proper standard: a roof that leaks after a repair, a rooflight that lets in water, plaster that cracks and falls away, or work that doesn't match what was agreed. The law expects building work to be carried out with reasonable care and skill, and where it isn't, the first remedy is for the builder to come back and put it right at their own cost.
Handled in a calm order, a defect is very often put right by the builder without any need for formal steps. This page explains how to tell a defect from other problems, what to record, how to ask for it to be fixed, and what to do if the builder disagrees. For the wider picture, see our guide to what to do when building work goes wrong.
Knowing what you have
A defect, a snag, or something else?
Each of these is handled a little differently, so it helps to name it correctly before you raise it.
A defect
Work that has failed or was done to a poor standard. Leaks, cracking, poor fixings, uneven finishes. The builder should put it right.
A snag
A small unfinished item or touch-up at the end of a job. Usually quick to fix and best dealt with on a single list. What is a snagging issue? explains the difference.
Not what was agreed
Different materials, a missing item, a different finish. Compare the work with the written quote and any agreed changes.
Not what you pictured
Done as agreed, but not how you imagined it. Changing it is normally new work, priced separately, rather than a defect.
Damage from the work
Damage to other parts of your home or belongings caused while the work was carried out. Often a matter for the builder's public liability insurance.
Later wear or damage
Problems caused by weather events, knocks or a lack of maintenance after the job, rather than by how the work was done.
The legal position
What consumer law says about defective work
Under the Consumer Rights Act 2015, a business providing a service to a consumer must carry it out with reasonable care and skill. For building work, that broadly means the standard you would expect of a competent builder doing that kind of job. Anything the builder said or wrote about the work that you relied on when deciding to go ahead can also form part of what was agreed. Materials the builder supplied as part of the job should be of satisfactory quality, fit for purpose and as described.
Where the work falls short, the Act gives you the right to ask the builder to repeat or repair the work. They must do it within a reasonable time, without causing you significant inconvenience, and they bear the cost. If putting it right isn't possible, or the builder fails to do it within a reasonable time, you may be entitled to a price reduction, which in some cases can be the whole of what you paid. You may also be able to claim for other losses the defect caused you.
A written workmanship warranty sits alongside these rights. It can give you more, such as a clear period during which the builder will return, but it generally cannot take away your statutory rights. Consumer rights for building work explains all of this in more detail.
Time limits apply to claims, and they are not the same in every part of the UK. The safest course is simply not to wait: raise a defect as soon as you notice it. How long do I have to complain? gives more background.
This is general information, not legal advice. Citizens Advice publishes free, current guidance on your rights when a service is not carried out properly. For advice on your particular situation, speak to a solicitor.
What to do
Getting a defect put right, step by step
A clear order keeps the conversation factual and gives the builder every chance to fix it.
Stop it getting worse
If water is getting in, protect the area and your belongings. Reasonable temporary measures are sensible and expected. Keep receipts, and record what you did and when.
Record the defect before anyone touches it
Dated photographs from a distance and close up, a short video if movement or water is involved, and a note of when you first noticed it. Keeping evidence and records covers what else to keep.
Check the quote and the warranty
Confirm what was agreed for the work in question, and when any warranty started and how long it runs. Note the relevant lines.
Tell the builder in writing
Describe the problem and where it is, attach photographs, say what you would like done and ask for a visit by a reasonable date. Refer to the warranty if you have one.
Let them inspect and put it right
Agree a date and give access. Once the work is done, check it, photograph it and confirm in writing that it has been completed, or what still needs doing.
Follow up if nothing happens
Write again, referring to your first message and its date, with a final date for a response. Raising a complaint with a builder sets out how to structure the letter.
The conversation
Keeping the discussion about facts
Good builders want to put their own work right. A defect left unresolved costs them their reputation, and a return visit is usually cheaper than a dispute. The way you raise it can make that easy or hard.
Be specific. "The flashing around the rooflight is letting water in at the top left corner, see photographs" is easy to act on. "The job is a mess" is not. If there are several problems, put them on a single numbered list so each one can be ticked off.
Meeting on site is often the quickest route. Walk round together, look at each item, and agree what will be done and when. Afterwards, send a short message confirming what was agreed. If the builder explains that something is not a defect, listen to the reasoning, and ask for it in writing if you are not convinced.
Be realistic about timing. A builder in the middle of another job may not be able to return tomorrow, but they should be able to give you a date. A leak is more urgent than a paint touch-up, and it is reasonable to say so.
Let the builder in when they come to look. Refusing access, or putting conditions on it that no builder could meet, can weaken your position later, because the law generally expects them to be given the chance to fix their own work. If trust has broken down, it is reasonable to be present during the visit, to ask what they intend to do before they start, and to photograph the work once it is finished.
When it's disputed
If the builder says it isn't a defect
Disagreements about whether something is a defect are common. There are sensible ways to settle them.
Steps that help
- Ask for the builder's explanation in writing
- Compare it with the quote and any product instructions
- Suggest a joint site visit to look at it together
- Get an independent report from a surveyor or specialist
- Share the report and invite a response
- Propose mediation if you still disagree
Steps to avoid
- Having it redone before the builder has seen it
- Withholding far more than the problem is worth
- Posting accusations about the builder online
- Letting weeks pass without writing anything down
- Paying extra for the builder to fix their own work
- Agreeing to a verbal fix with no record
Independent evidence
When an independent report is worth it
If the builder disputes the problem, an independent opinion is often the fastest way through. A chartered building surveyor, or a specialist in the relevant trade, can inspect the work, say whether it was done to a reasonable standard, explain what is wrong and estimate what it would cost to put right. The Royal Institution of Chartered Surveyors (RICS) lists its members on its website.
A report costs money, so weigh the fee against the size of the problem. For a small defect it may not be worth it. For a larger one, or where you may later need to show what went wrong, it can be decisive. Choose someone with no connection to either side, and ask them to write the report in plain language with photographs.
Share the report with the builder and ask for their response by a set date. Faced with an independent view, many disputes settle quickly. How do I prove work was defective? and what if the contractor disputes the problem? go into more detail.
Money and remedial work
Payments, and bringing in someone else
If the balance is still due when a defect appears, it is reasonable to agree with the builder that an amount in proportion to the problem waits until it is fixed. Tell them in writing what you are holding and why, and pay the rest as agreed. When to withhold payment explains the principles.
If the builder will not or cannot put it right after a fair chance, you may need someone else to do it. Record the defect fully first, get a written quote for the remedial work, and keep every receipt, because the cost may be something you can seek from the original builder. Getting remedial work done covers the process, and who pays to put defects right? gives the short answer.
If the defect has caused damage elsewhere in your home, such as water staining a ceiling, tell your home insurer as well. Your policy may cover some of it, and the insurer can advise on what they need.
Where Mortaro fits
Telling us, and what we do next
If Mortaro coordinated your project, tell us about the defect by phone or email, with photographs if you can. We raise it with your contractor on your behalf, push for a visit and a resolution, and keep you updated. Your contractor, named in your quotation, provides the workmanship warranty: a minimum of 12 months across our network, usually from completion, with exact terms in your quotation.
The contractual remedy for defective work is against your contractor, and we do not guarantee the work ourselves. Contractors who fail to put their work right are removed from our network. Putting things right sets out our process.
Straight answers
Questions about defective workmanship
How long should I give a builder to fix a defect?
There is no single answer. It depends on the problem and how urgent it is. Agree a realistic date for a visit, confirm it in writing, and treat a leak or safety issue as more urgent than a cosmetic one.
Does the builder have to pay to fix their own defects?
In general, yes. Where work was not done with reasonable care and skill, putting it right should be at the builder's cost, not yours.
What if the defect appears after the warranty has ended?
Your statutory rights do not simply end with the warranty. Whether you still have a claim depends on the circumstances and time limits, so check with Citizens Advice or a solicitor.
Can I get another builder to fix it and send the bill to the first one?
Generally only after the first builder has had a fair chance to put it right and failed to. Record everything before any remedial work starts, and take advice if a significant amount is involved.
The same defect has come back after a repair. What now?
Raise it again in writing, noting the date of the earlier repair and that the problem has returned. A repeated failure is a good point at which to ask for an independent opinion on the cause, so that the next repair deals with it properly.
Start here
Tell us about the work you have in mind
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