6 questions to ask a plumber before you hire

Are you Gas Safe registered, and for what?

Ask it even when the job is not gas, because the answer tells you what else they can help with. Where it is gas, ask for the registration number and check it on the public register, and confirm the categories cover the appliance. Boilers, cookers and fires are separate categories, and commercial appliances are separate again.

For an unvented cylinder, ask about G3 specifically, which is a different qualification from Gas Safe registration.

Is the price fixed or hourly, and what is not included?

Both are legitimate. What matters is knowing which you have agreed to and what sits outside it. The exclusions that most often become extras are making good the plaster after cutting into walls for pipes, replacing valves found seized on the day, disposal of an old appliance, and any second trade the job turns out to need.

On an emergency call, ask whether the first hour is a call-out fee with time on top or a minimum charge including labour.

What happens if you find something unexpected?

Older properties often have something unexpected behind a panel. The useful thing to agree is what the plumber does when that happens: most stop and phone you before carrying on, and it is worth confirming that at the start.

Ask for a figure above which they will call before proceeding. Fifty or a hundred pounds is a normal threshold and it keeps everyone clear on costs.

Who else will the job need?

Bathrooms need a tiler, a plasterer and an electrician. Electric showers need an electrician. Kitchens need a fitter. Ask who is arranging and sequencing them, because a job with four trades runs far more smoothly when one person co-ordinates them.

If the plumber is subcontracting, ask who you pay and who is responsible for putting any problem right.

What paperwork will I get?

For gas work, a Gas Safe building regulations notification and a commissioning record. For an unvented cylinder, a G3 certificate and a building control notification. For a boiler, the manufacturer's warranty registration. For a landlord gas safety check, the landlord gas safety record itself within 28 days.

Ask when each arrives. Paperwork is easy to lose track of once the work is finished, and it is what a future buyer's solicitor asks for.

Common questions

Should I pay a deposit?

For a job with materials to buy, a deposit covering the materials is reasonable, and it is normal for it to stay in proportion to them rather than approach half the total.

What if I am not happy with the work?

Raise it immediately and in writing. Most plumbers will return and put it right. For gas work you are concerned about, Gas Safe Register will inspect the installation at no charge.

Do I need three quotes?

Two or three for anything over about a thousand pounds. For a tap change, one. Comparing quotes only works when they cover the same scope, so send the same written description to each.