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.
Blocked drains — causes and what a plumber checks
Slow-draining sinks are usually a local blockage (grease, hair, food waste) that a plumber can often clear with rodding or a drain snake. A blockage affecting multiple fixtures at once, or gurgling sounds from other drains, points to something further down the system — sometimes needing a drain camera survey rather than guesswork.
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.
Water-based underfloor heating, what's involved
Unlike electric underfloor heating, a water-based system runs off your boiler via a manifold and needs the floor buildup to accommodate the pipework — usually easier to fit during a renovation than retrofit into a finished floor. It's often paired with a lower-temperature heating setup than radiators use.
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.
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.
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 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.