Leak Detection London — Find and Fix Hidden Leaks Fast

A rising water bill with no change in usage is the single most reliable sign of a hidden leak, and it's worth acting on before it causes structural damage or a mould problem.

• Your water bill has increased with no obvious change in usage
• A damp patch, stain or bubbling paint on a wall or ceiling that keeps returning
• A musty or damp smell in one room that won't clear with ventilation
• The sound of running or dripping water when every tap and appliance is switched off
• A water meter that keeps spinning with the whole house's water turned off
• Warm patches on floor tiles, which can point to a leaking underfloor heating pipe

If you're seeing any of these in a London flat or house, it's worth getting a leak checked before it spreads — call 07460 824073. If you can already see where the water is coming from, our guides to a leak under the sink and a leak under the bath walk through what to check first.

Most leak detection call-outs in London turn out to be one of a handful of causes, and we carry the parts to repair the majority of them on the same visit.

• Leaking or corroded supply pipes hidden under floors or behind walls
• Failed joints, fittings or push-fit connections in copper or plastic pipework
• Leaks from a shower tray, bath or wet room seal soaking into the floor below
• Leaking waste pipes under sinks, in bathroom voids or behind a boxed-in bath
• Leaking underfloor heating pipes and manifold connections
• Slow leaks from an outside stopcock, external tap or garden supply pipe

For jobs traced to a specific fixture rather than hidden pipework, our CCTV drain survey service can rule out (or confirm) a drainage cause working alongside the leak trace.

Trace and access is the diagnostic step most home insurers require before they'll settle a leak claim, and it means locating the exact source of a hidden leak with the minimum disruption needed to confirm it. As a trace and access plumber, we use acoustic listening equipment and thermal imaging first, so any cutting into a wall, floor or ceiling void is targeted to the confirmed leak location rather than a guess.

Once the leak is traced, we document the finding — photos, location and likely cause — in a form most London insurers will accept as part of a claim, then carry out the repair itself or hand over to a restoration contractor if reinstatement work (plastering, flooring, redecoration) is needed beyond the plumbing fix. If your policy requires trace and access as a condition of cover, tell us when you call so we can quote and document the job accordingly.

Most East and Central London leak call-outs get a plumber on site the same day, because we're based centrally in E1 rather than dispatching from outside London. A leak that's actively coming through a ceiling or spreading fast should be treated as an emergency — call us straight away and we'll prioritise it alongside our emergency plumber service. A slow leak that's only shown up as a higher bill can usually be booked in for a convenient same-week slot instead.

We regularly cover Tower Hamlets, Hackney, Islington, Newham, Southwark, Canary Wharf, Shoreditch, Whitechapel, Bethnal Green and Mile End, and take on jobs across the wider London area from our Commercial Road base.

Tracing a leak accurately before opening anything up saves you money and disruption, because the alternative — lifting floors or stripping walls speculatively to find a pipe — is slower, messier and more expensive to make good afterwards. Acoustic detection listens for the specific sound water makes escaping a pressurised pipe, while thermal imaging picks up the temperature difference a leak leaves behind on a wall or floor surface, and combining both gives a tighter, more reliable fix on the location.

The cost depends on how quickly the leak can be traced, whether access work is needed, and whether the repair can be completed on the same visit — which is why we always give a free, no-obligation quote before starting rather than a figure over the phone. For a full breakdown of how leak detection and repair jobs are priced, see our pricing page.

From tracing a leak beneath a kitchen floor in Bow to an insurance trace and access job on a leaking bathroom wall in Islington, RenoPlumb handles leak detection and repair across East and Central London every week. See more examples on our Our Work page.