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.
Understanding the labour vs materials split
Materials — pipework, fittings, a new boiler or bathroom suite — are often a smaller share of a plumbing quote than labour, particularly for jobs involving lifting floors or chasing walls. If a quote looks unusually cheap, check whether it specifies the same brand/quality of fittings as a competing quote, not just a lower labour rate.
Workmanship guarantees on plumbing work
Most registered plumbers offer a workmanship guarantee separate from any manufacturer's warranty on parts like a boiler or a shower unit — commonly 12 months upwards. Ask what's specifically covered: a guarantee on a bathroom refit should cover the plumbing work itself, not just the visible fittings.
Heat pumps and eco-friendly heating options
Some plumbers also work on or alongside heat pump installations, though this is often a joint job with a heating engineer for the heat pump unit itself. If you're considering moving away from a gas boiler, it's worth asking whether your plumber does this work directly or partners with someone who does.
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.
Plumbing in a washing machine or dishwasher
Both need a cold water supply, a drain connection, and in most cases their own isolation valves so they can be disconnected without turning off water to the whole property. Using a shared valve with another appliance is a common shortcut that makes future repairs more disruptive than it needs to be.
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.
First fix and second fix plumbing
On a new build or extension, "first fix" is running pipework through walls and floors before they're closed up; "second fix" is fitting the visible taps, radiators and appliances once decorating is done. Timing this with other trades on site matters — pipework needs to be pressure-tested before it's covered over, not after.