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For homeowners

The complete guide to avoiding cowboy builders in the UK

I have spent 25 years in the building trade, and a lot of that time helping families put right work somebody else ruined. Most of them were careful people. They asked around, they got quotes, they checked a review page. Here is what I check, and what I wish every one of them had known first.

By Graham Nash Published Last reviewed

Why this happens to careful people

Almost nobody hands money to a builder they think is dishonest. The families I have helped did the normal things. They got three quotes. They looked at a profile with good reviews on it. Some of them used a neighbour's recommendation. It still went wrong.

It goes wrong because the checks most of us know to do are checks on a company, and a company is the easiest thing in this trade to replace. The person is the part that carries the history, and the person is the part nobody looks at.

The scale of it is not small. The Federation of Master Builders has estimated the cost to homeowners at over 14 billion pounds across five years, and separate research has put the share of British homeowners who say they have been a victim of a cowboy builder at more than half. Those are estimates rather than counts, and they are still the right order of magnitude for what I see. This is not a rare accident. It is the ordinary outcome of a trade with no licence, no register and no memory.

The warning signs worth acting on

Some of these are obvious once somebody says them out loud. That is fine. The point is not that they are clever, it is that they are the ones that keep turning up in the jobs I get called into afterwards.

One on its own is not proof of anything. A good tradesperson can be bad at paperwork. But two or three together, and I would walk away, and I say that as somebody who has been on the receiving end of people walking away from me.

  • They want a large payment before anything starts, and they have a reason why today is different.
  • The quote is one number on one page, with no breakdown of what it covers.
  • They will not put the start date, the finish date or the specification in writing.
  • They knocked on your door, or they happened to be working nearby and noticed your roof.
  • The price drops sharply when you hesitate. A real price does not have that much room in it.
  • They ask to be paid into a personal account, or in cash, or into a name that is not the business name.
  • They are pushing you to decide now, before you have spoken to anyone else.
  • You cannot find an address for the business that is anything other than a mobile number.
  • They tell you the work does not need Building Regulations approval when you think it might, or they will not say who is responsible for getting it.

How to check what you are shown

Anybody can print a logo. I am not being cynical about the trade, I am being accurate about paper. Every one of these takes a few minutes and costs nothing, and the person who is genuine will not mind you doing them.

Insurance, and the bit people miss

Ask for the certificate rather than the answer. Then ring the insurer named on it and ask whether the policy is live and what it covers. A certificate is a snapshot of one day. A policy is a thing that can lapse the week after it was printed.

There are two covers and they do different jobs. Public liability covers damage to you and your property. Employers' liability is a legal requirement the moment somebody has an employee, and it covers the people working on your house. A builder turning up with two lads and no employers' liability is not a problem you can wave away as their business: if somebody is hurt on your property it can very easily end up at your door, and you do not want to be finding out where the line falls while it is happening.

Then check your own. Most home insurance policies expect to be told about building work, and for anything structural they often want notice in advance. People discover this at the worst possible moment. A phone call to your own insurer before the work starts costs nothing and keeps the cover you are already paying for.

Trade bodies and qualifications

Membership badges are worth something, but only if you check them at the source rather than on the van. Every serious scheme has a public register you can search yourself, and it takes about a minute.

Some work is genuinely regulated, and there a register is not optional. Gas work must be done by somebody on the Gas Safe Register, which covers the whole United Kingdom. If somebody tells you their mate can do the gas, that is the end of the conversation.

Electrical work is regulated differently and the rules are not the same across the UK. In England and Wales it sits under Part P of the Building Regulations, Scotland has its own electrical safety standard, and Northern Ireland handles it differently again. What matters for you is the same everywhere: certain work has to be either done by an electrician registered with a competent person scheme, who can self-certify it, or notified to building control so they can inspect it. Ask which of those is happening before the work starts, and ask for the certificate afterwards. There is no single official register of electricians in the way there is for gas, so check whichever scheme they name on that scheme's own site.

The company reset, and why a clean record can mean nothing

This is the one I most want you to take away, because it is what makes all the other checks less useful than they look, and almost nobody outside the trade knows about it.

Vetting checks a company. A company is a piece of paper, and replacing one costs a fee and an afternoon. So a builder who has left a trail of unfinished jobs behind one limited company can close it, register another tomorrow morning, and present a completely clean record. New company, no history, no reviews, nothing to find. The person has not changed. Only the paperwork has. What almost nobody does, us included until we built around it, is keep a ban attached to the person rather than to the company.

So check the person. Start by asking for the company registration number and the registered office address, and check the name on the quote matches the name on the insurance certificate and the company you find. A builder who cannot give you a number may not be trading as a company at all, which is worth knowing early, because it changes who you would be pursuing if this went wrong.

Then search that number on Companies House, which is free and public. Open the officers list and click the director's own name. That gives you the other companies filed against that officer record, when each started and when each ended.

What you are looking for is a run of short-lived companies, often in the same trade and the same area. One dissolved company means very little. Businesses fail, and some of the best tradespeople I know have had one go under. Four in six years, each lasting about eighteen months, is not bad luck. That is a method.

Two things the search will not show you, so that you do not over-trust it. Appointments are grouped by the details filed, not by a verified identity, so the same person under a variant spelling or an old address can appear as two separate people. And it only shows roles where they were an officer, so somebody running a business through a relative's name does not show up at all. Check whether the person you are dealing with is even on the officers list. If they are not, ask why.

It takes about ten minutes and it is still the single most useful thing in this guide.

How to choose between the people who quote

Three quotes is the advice everybody gives and it is good advice, but it is only useful if you can tell what you are comparing. Two builders can quote the same job and mean completely different work, and the cheaper one is often cheaper because it leaves out the thing that turns out to matter.

So before you compare prices, make them comparable. Write down the job once, in as much detail as you can manage, and give the same description to everybody. Then when the quotes come back you are reading differences in price rather than differences in what they thought you wanted.

  • Ask what is excluded, not what is included. The exclusions are where the surprises live.
  • Ask who is actually doing the work, and whether any of it is being subcontracted. You want to know whose insurance covers what.
  • Ask what happens to the price if something is found once the work is opened up, and get the answer in writing.
  • Ask for the address of a job like yours that they finished at least a year ago. Recent work looks good. Work that has been through a winter tells you more.
  • Ask for references and then actually ring them, and ask the homeowner what went wrong rather than whether they were happy. Every job has something. How it was handled is the answer you want.
  • Notice who asks you questions. Somebody who quotes a job like yours without asking anything about it has not priced your job, they have priced a job.

A recommendation is a starting point, not a check

A neighbour's recommendation is the most common way people find a builder and it is genuinely worth having. What it is not is a substitute for the checks above.

Your neighbour saw one job. They probably did not see the insurance, they did not look at Companies House, and if their job went fine they have no idea what happens when one does not. I have been called into plenty of jobs that started with a recommendation from somebody happy. Take the name gratefully, then check it the same way you would check a stranger.

What to agree before any money moves

Most of the disputes I get called into were not caused by bad building. They were caused by nobody writing down what was included, so when the argument came there was nothing to point at.

The non-negotiables are in the survival kit below and I am not going to repeat them here. What the kit has no room for is the detail that decides arguments.

Price the work in stages, and describe each stage so precisely that a stranger could walk in and tell you whether it was finished. That is the test. Vague stages are where disputes live, because two reasonable people can genuinely disagree about whether something described as first fix is done.

Agree in writing what counts as extra, because that is the argument you will have. Agree how an extra gets priced and approved before it is carried out, not afterwards.

Agree what happens at the end. Hold back a final payment until the work is genuinely complete and you have the paperwork, meaning the building control sign-off and any certificates. It is normal to keep a small retention for a period after completion against things that only show up later. Say so at the start rather than raising it when the final invoice arrives.

If it has already started going wrong

If you are here because it is already happening rather than because you are planning, the advice you need is different from anything above, and the most important part of it is this.

Start keeping records today, and do it before you tell them you are unhappy. Photographs, payment records, every message, in that order of urgency. What you gather before the argument is worth far more than anything you gather after it, and that ordering is the whole of the advice.

From Graham's survival kit

The short version of the checks this guide goes into. Each one links to the full kit.

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Questions homeowners ask

Do builders need to be licensed in the UK?

No. There is no general licence to be a builder in the UK, and most people are surprised by that. Specific work is regulated rather than the trade as a whole: gas work requires Gas Safe registration, and electrical work is covered by building regulations that differ between England and Wales, Scotland and Northern Ireland. Everything else rests on the checks you do yourself, which is what this guide is for.

What checks should I do before hiring a builder?

Ask for both insurance certificates and confirm them with the insurer. Check any trade-body membership on that body's own public register rather than on the van. Look the director up on Companies House, not just the company. Get the work priced in stages in writing, with a clear description of what each stage includes.

How do I know if a builder is legit?

Legitimate is not the same as registered, because there is no register to be on. What you are really checking is whether the person has a history you can see, insurance that is live, and a willingness to put the specification and the stage payments in writing. Somebody who is happy with all three is usually fine. Somebody who resists any of them is telling you something.

Is a cheap quote always a bad sign?

No, but a quote that is far below the others deserves a question rather than a celebration. Ask what is in it that the others have left out, and what happens to the price if something is found once the work opens up. A price that drops sharply the moment you hesitate was never a real price.

What are the signs of a cowboy builder?

The ones worth acting on are above, and the pattern behind them is simple: pressure to decide quickly, reluctance to put things in writing, and a payment arrangement that moves risk onto you. Any one of those can have an innocent explanation. Two or three together is a reason to walk away.

How do I find a good builder without being ripped off?

Take recommendations as a starting point, then check the person rather than the company, confirm both insurances with the insurer, compare like-for-like quotes built from one written description of the job, and structure the payments in stages against work you can see. None of that guarantees anything. All of it moves the odds a long way, and it is what I do before I would trust somebody with my own family's home.

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