How can you tell if a pipe is leaking inside a wall?
Compare use of fixtures, meter movement and whether wet marks persist in dry weather.
Read guide →DampUK practical guides
Plumbing leaks
Leaks from supplies and wastes may be intermittent, hidden or dependent on use. Tracking when moisture appears is often more useful than the size of the stain.
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Questions answered in this section
Why is water coming through the ceiling below the bathroom?
Bath seals, shower trays, wastes and supply pipes need different tests.
Read guide →Can a shower leak without water on the floor?
Water can pass behind tiles or beneath a tray while the visible surface stays dry.
Read guide →Why is my ceiling damp below the bath?
An overflow or waste joint can leak only when the bath is filled or emptied.
Read guide →How can a leak beneath a concrete floor be found?
Pressure tests and specialist location methods may narrow the source without immediately excavating.
Read guide →Could my central heating system be leaking?
Falling sealed-system pressure can be a clue, but faulty expansion vessels also affect readings.
Read guide →Why is water appearing around the base of my toilet?
Condensation, failed seals and supply connections should be distinguished from waste leakage.
Read guide →Can a small hidden pipe leak cause serious damage?
Long-term wetting can affect plaster, floors and nearby electrical installations.
Read guide →Why does a wall get damp when the shower runs?
Water may escape at corners, pipe entries, grout joints or shower waste connections.
Read guide →What causes a leak behind kitchen units?
Check isolation valves, appliance hoses, sink wastes and pipe joints.
Read guide →Can a dishwasher leak behind its cabinet?
Supply hoses, drain connections and appliance seals can release water without an obvious puddle.
Read guide →Could a washing machine hose be leaking?
Inspect hoses and fittings without moving a live appliance unsafely.
Read guide →Why does water appear when the toilet flushes?
Waste connections may leak only under discharge, unlike constant supply leaks.
Read guide →Can bathroom silicone fail without looking damaged?
Small separations and movement at tray edges can be hard to see.
Read guide →Why is my hot water cylinder cupboard damp?
Look at valves, discharge pipework, condensation and adjacent plumbing; do not interfere with safety devices.
Read guide →Why is a kitchen ceiling stained but dry today?
Intermittent use and old staining may explain the pattern; confirm whether moisture is active.
Read guide →Can a pressurised water system leak without a puddle?
Concealed pipe routes can carry water into floors, voids and wall linings.
Read guide →How do plumbers trace a concealed water leak?
System isolation, moisture mapping and pressure testing help narrow the search.
Read guide →Should a plumber lift floors to find a leak?
Agree a reasoned sequence of non-destructive checks before intrusive work.
Read guide →Can a dripping tap cause damp inside a wall?
Escaping water around fittings or back plates may travel into concealed spaces.
Read guide →Why is water coming through a ceiling near a light?
Water and electrical wiring create an immediate safety concern.
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