What to ask a plumber before they start

Asking the right questions takes five minutes and can save you hundreds. Here they are, along with what a decent answer sounds like.

Plumbing jobs go wrong for the same reasons every time: nobody agreed a price, nobody agreed what was being done, and nobody checked whether the person doing the gas work was allowed to. There are plumbers listed across the WotsItCalled directory, from sole traders to proper outfits. The good ones won’t mind any of these questions, and the dodgy ones will.

Sort the job before you sort the plumber

Work out what you’re dealing with before you ring anyone, because how you describe it on the phone decides who’s right for the job.

• Dripping tap, blocked sink, leaky radiator valve: bread and butter for any general plumber. You want someone local who won’t charge a fortune just to turn up.
• Anything involving gas or a boiler: this is Gas Safe territory, and there’s no wiggle room. If they’re not on the Gas Safe register, they shouldn’t touch it.
• New bathroom, kitchen sink plumbing, full pipe replacement: this is project work. Get quotes in writing, a timeline, and ideally photos of jobs they’ve done before.
• Burst pipe at midnight: that’s an emergency call-out, and price comes second. You need someone who answers the phone and can get there fast.

Get a bathroom fitter out at 11pm for a leak and you’ll likely end up paying twice.

Five questions to ask before they start

The first phone call tells you most of what you need. Ask these five and listen to how they answer as well as what they say.

1. Are you Gas Safe registered, and what’s your number? If the job touches gas, nothing else matters as much. A genuine plumber gives you the number straight away, and checking it at gassaferegister.co.uk takes about ten seconds.
2. Can I get a written quote before any work starts? A price over the phone isn’t worth much. A proper plumber will come and look, then put the price in writing. If they dodge a site visit for anything bigger than a washer change, be wary.
3. Is that a fixed price or an estimate? Fixed means that’s what you’ll pay unless the job changes. An estimate can go up, and it usually does, so know which one you’re agreeing to.
4. How’s the call-out charged? Some charge a flat call-out fee, some fold it into the hourly rate, and some waive it if you go ahead with the work. Any of those is fair if they tell you up front. If you only find out at the end, something’s off.
5. When can you get here and how long will it take? You’re planning your week, not interrogating them. A decent plumber gives you a straight answer, and one who can’t commit to a time slot is usually juggling too much.

On bigger jobs, also ask who’ll be doing the work. Some outfits quote for the job and then send someone else on the day. That’s fine if they’re good, but you should be told.

Red flags that should end the conversation

If you hear any of these, ring the next one on your list.

• Cash only, no receipt. Everyone takes cash, but a proper plumber still gives you a receipt. Insisting on cash with nothing in writing is a reason to walk away.
• Vans with no business name, no insurance details. Not a dealbreaker for a sole trader on its own, but alongside anything else on this list it starts to look like a pattern.
• A quote far lower than the others. Sometimes it’s an honest sole trader keeping overheads down. More often it’s someone planning to bump the price halfway through with “unexpected issues”.
• Pressure to start today. Unless it’s a real emergency, urgency is a sales tactic. Decent plumbers are usually booked a few days out anyway.

Where to find one near you

The plumbers directory on WotsItCalled is free to browse and covers every major UK city. For someone local, the city pages are the quickest way in: plumbers in Liverpool, Manchester, Birmingham, Wirral and the rest. There’s no signup or account, just listings, phone numbers and reviews.

After the job: what a decent plumber leaves behind

A good plumber tidies up on the way out. You’re not expecting a deep clean, just the basics: old parts bagged and labelled, drip trays emptied, offcuts swept up and the work area wiped down. If you’ve had a new boiler or new valves fitted, they should show you how it works, including where the isolation valve is, how to top up the pressure and what the warning lights mean.

• A written invoice. Itemised, dated, with their business details and a VAT number if they’re registered.
• Warranty details. Most plumbers guarantee their labour for 12 months. A new boiler also carries the manufacturer’s warranty, usually 5 to 10 years if it’s registered properly.
• Registration paperwork. For a new boiler, Gas Safe notifies Building Control automatically, and a certificate should arrive in the post within a fortnight.
• Benchmark logbook entry. New boilers come with a Benchmark commissioning checklist. Make sure it’s filled in and signed, because the manufacturer’s warranty depends on it.

The short version

• Emergency, gas and project work need three different shortlists, so know which you’ve got before you ring round.
• Gas Safe registration is a legal requirement for gas and boiler work. Check the number on the register.
• Get a written quote, and go for a fixed price over an estimate.
• Confirm the call-out charge up front so the bill holds no surprises.
• Vague timings, cash only or pressure to start today are all reasons to try someone else.

WotsItCalled is a free UK business directory. No signup, no catch. Find the place everyone’s on about, or browse the full plumbers directory.