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.
How plumbing quotes work
Describe the job, including whether it's an emergency, a planned repair, or a full installation, and mention access — under a suspended floor is very different from behind fitted units. Plumbers use this for an initial estimate; the final price is usually confirmed once they've seen the fault or the space in person.
Combi vs system vs conventional boilers
A combi boiler heats water on demand with no separate tank, suits smaller properties with one bathroom. A system boiler uses a hot water cylinder but no cold water tank, better for higher demand. A conventional (regular) boiler uses both a cylinder and a tank, common in older properties and useful where mains pressure is poor.
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.
How long does plumbing work take?
A tap or valve replacement is usually under an hour. A full bathroom refit commonly takes 5 to 10 working days depending on scope, plus time for tiling and decorating that isn't part of the plumbing work itself. A boiler swap is typically a one-day job if it's a straightforward like-for-like replacement.
Hard water and your plumbing
In hard water areas, limescale builds up inside pipes, taps, showerheads and boiler heat exchangers over time, gradually reducing efficiency and flow. A plumber working in a hard water area may recommend a water softener or scale inhibitor as part of a boiler installation, particularly for a system that's expected to last 10+ years.
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.
Protecting pipes in cold weather
Pipes in unheated spaces — lofts, garages, outbuildings — are the most common source of a winter burst pipe once temperatures drop below freezing for a sustained period. Lagging exposed pipework and keeping heating on a low constant setting during a cold snap, rather than off, are the two most effective preventive steps.