16 Questions to ask your builder

Finding a good builder

The best way is to get a recommendation. Ask if the builder started and finished on time, kept the site tidy, cleared up at the end, struck to the agreed price and overall did a good job of work. 

Remember, however, some problems take years to become evident when cowboy builders have charged for work they don’t actually do – for example, installing membranes under a concrete floor, or putting trunking round wiring in a screed. By the time you realise, the builder and their company may have disappeared.

You can find builders in your area who are registered with the Federation of Master Builders from their website. However, while standards for joining the Federation are high, it does not inspect the work of members. And beware – some unscrupulous builders put the Federation’s logo on their letterhead even though they are not members. Ask to see their certificate of membership as proof.

You can also look for a builder under the Quality Mark scheme (tel: 0845 300 8040), a government-backed register with details of more than 500 firms. Finally you might try Which Local which has been set up by the Consumers Association to allow satisfied customers to recommend companies which have done good work for them.

16 questions for your builder

Make sure you speak to them in case the builder has invented them.  Ask to see the work and forget about anyone who won’t show you work they have done.  Ask to see some older work as well as a recent job since there will have been more time for faults to become apparent.

It’s better if the builder has done something at least reasonably similar or he could be learning how to do it at your expense.

A builder can demonstrate this by producing records or other paperwork like bank statements or contracts.

It’s a bad sign if they don’t.  While an individual tradesman can operate from home, a builder needs space to store equipment and supplies.  A home address is all right as an office address but a builder needs premises somewhere.

References from a supplier about a builder’s credit facilities and payment are a good indication of financial stability and management.  Also, check how long he has been with his current bank – beware someone who keeps changing his bank as this can indicate financial problems. 

Any changes should be put in writing and, if there is a knock-on effect on the costs and finish date, these should be put in writing too as an addition to the quotation or contract.  Please do not venture onto a project thinking you can easily change your mind as you go along – most changes of mind will cost you money and cause delay.

It is much better if your builder has an established team.  He may find it difficult to impose his own standards on people he has never seen before, like migrant tradesmen.  If he is starting off someone new he should supervise him long enough to confirm his competence before leaving the site.  Additionally, if a builder needs to hire sub-contractors – e.g. for central heating – these should be people whose work he knows.

Generally look for a builder who is VAT registered.  The VAT threshold is currently £64,000 and someone with a turnover below that cannot be doing very much work.  If someone offers to waive VAT if you pay cash, beware. Tax avoidance is not the sign of the honest type you want and it puts you in a weak position in the event of a dispute.

It’s essential.  Never accept a verbal assurance that it will cost ‘about £10,000’.  It’s important to distinguish between an estimate and a quotation.  An estimate is only an estimate, it has no binding force.  A quotation is an undertaking to do the job for a stated price.  You can move from an estimate to a quotation when you have established exactly what is to be done.  You may want to change a few things to save money after seeing the estimate.  The final detailed quotation should include all the work to be done, date of completion, security and safety, catering and toilet arrangements, disposal of rubbish, water and power supplies, hours of working and so on.  But better still, ask for a written contract.  You can download a standard one from the Federation of Master Builders website (www.fmb.org.uk).  Once the builder has signed it, you will be much better covered.

Cross-examine your prospective builders on how realistic proposed start dates really are. Don’t push for an early start if this is unrealistic. On larger projects ask for a timetable so you can see if the job is slipping behind.

You will need to relate this to the size of his workforce. A small workforce and a lot of projects could mean he is overstretched. If this means excessive use of casual labour or sub-contractors it could spell trouble – see below.

Your builder is legally obliged to have both public and employers liability insurance – ask to see his certificates.  He should have at least £2 million cover.  He should also have other insurance to cover other kinds of problem which may arise – again, ask to see his certificate

It’s much better if he does although it can be valueless in practice if he goes out of business.  As an alternative, you can yourself purchase a 10-year warranty to cover building work.  While this means you will have to bear the cost of insurance yourself, at least you will be covered.

If he does, forget about him.  He should be in sufficiently good financial shape to purchase supplies without needing your cash up-front to do it.  The only exception would where some rare kind of very expensive initial purchase has to be made.

If the job is big enough – for example, if it lasts four weeks or more – then agree stage payments which should be precisely defined. Agree what percentage of the total bill you will retain until you can be sure that all the work is satisfactory, which should be 10-20%. If you pay in cash, you will be in a very weak position in the event of any dispute. It is better to pay by bank transfer, cheque or credit card. If you can use the latter, then the card provider will be jointly liable for payment which may help you in the event of a dispute. Check that your builder will accept payment by credit card. Many do not – understandably, because of the fees charged by the card.


You will obviously want to keep an eye on how the work is progressing.  If you are at home during the work, this is easy.  If not, try and make time for visits.  Also ask when particular tasks are to be done which involve things like pipes, wiring or damp-proof membranes being covered up and make sure all is well before they disappear. Dropping in unannounced from time to time may not catch anyone out but the knowledge that you might should at least be a deterrent to a bit of cheating.  If a builder seems negative about this, don’t employ him.  You want someone who is proud of his work.


Getting the right price

Don’t rush into finding someone. Obtain at least three quotations. The Building Cost Information Service will give you an idea of how much a job should cost. Don’t necessarily go for the cheapest quote; take into account the answers to your questions.

Do you need planning permission?

Find out if you need planning permission or if building regulations apply to your job. If it qualifies as ‘building works’, which includes everything from building an extension down to installing a new window or boiler, you are obliged to have it inspected and certified by your local council (which will require a fee). Planning permission covers larger projects and for this you need to apply to your local council planning department with plans.

The department responsible at your local council is called Building Control and they will tell you all you need to know. You will need the certificates when you sell your house as the buyer’s solicitor will want to see them.

Hiring a professional

An alternative for you is to hire an architect or surveyor to help you plan the job and then oversee it, which can be a good idea on larger projects. Typically, they will charge 10-13% of the value of the work but can save you money by knowing the right builder to choose, bearing down on costs and making sure you get good quality work.

What to do if something goes wrong

Complain to your builder as soon as you spot something you don’t like the look of.  The longer you leave it, the more difficult it will become to sort things out.  If things get serious, you can seek help from the Federation of Master Builders or the Quality Mark scheme which run arbitration services.  

Otherwise, you will need to engage professionals on your side which will send costs shooting up – and could leave you living in a building site for months if things are not resolved.


If help is required from a specialist like a structural engineer, drainage consultant or central heating engineer, ask your builder if he has access to someone, how he proposes to use them and exactly where responsibility lies for their contribution.


Make sure you have Public Liability insurance in case something affects neighbours or passers-by.  

You should inform your insurance company about building work as having builders in may affect the terms of your Buildings and Contents policy.