Three steps to hiring the right plumber
First, check they're registered with a WaterSafe scheme (or Gas Safe too, if the job needs it) and ask for the registration number. Second, get a written quote that separates labour from parts. Third, ask what happens if the job uncovers a bigger problem — a good plumber will tell you before continuing, not after.
What WaterSafe registration means
WaterSafe is the umbrella body for the UK's Approved Contractor Person schemes (including APHC, CIPHE, WIAPS and SNIPEF). A WaterSafe-approved plumber has been assessed on their knowledge of the Water Fittings Regulations, which exist to stop poor installation work or substandard products contaminating the drinking water supply — not just general plumbing competence.
Common plumbing myths, busted
"A dripping tap is just cosmetic" — left long enough it wastes real water and can damage the fitting further. "Any handyman can fit a boiler" — boiler work involving gas connections legally needs a Gas Safe engineer, not just a plumber. "Bleeding a radiator fixes all heating faults" — it only helps with trapped air, not pressure or pump issues.
Low water pressure — common causes
Low pressure can come from a partially closed stopcock, a fault with the water company's supply, scale build-up in old pipework, or (for a shower specifically) the type of shower valve fitted. A plumber can usually diagnose which of these it is by checking pressure at more than one fixture, rather than assuming it's the mains supply.
What a boiler fault code usually means
Modern combi boilers display a fault code when something's wrong rather than just stopping — the exact meaning varies by manufacturer, but common causes behind a "no heat" code include low pressure, a faulty sensor, or an ignition fault. Note the code before calling a plumber; it speeds up diagnosis considerably.
When plumbing work needs a Gas Safe engineer instead
Plumbers can install and repair most water systems, but any work on a gas appliance or gas pipework — a boiler, a gas fire, a gas hob — is illegal for anyone who isn't on the Gas Safe Register, by law. If a job involves both plumbing and a gas connection (moving a boiler, for example), check whether your plumber is also Gas Safe registered before booking.
Outside taps and garden plumbing
An outside tap needs its own isolation valve and, in colder areas, either an internal shut-off you can drain down for winter or a proper anti-frost design — a poorly installed one is a common cause of a burst pipe in cold weather. This is separate from the electrical requirements for any pond or irrigation pump also being installed.
What is a power flush and do you need one?
A power flush clears sludge and debris from a central heating system's radiators and pipework using a pumped chemical flush — usually recommended if radiators are cold at the bottom, or before installing a new boiler onto an older system, so the new boiler isn't immediately clogged by old sludge.