London Leak Specialist
No find, no fee leak detection

London Leak Detection Specialists, Called In When the Plumber Cannot Find It

Across our last 400 surveys we found the cause in 95 out of every 100. Acoustic, thermal imaging, tracer gas and calibrated moisture mapping on every visit, across London and out to the M25, 24 hours a day. A fixed £160 an hour covers finding the leak, isolating it and repairing it, the same rate even when tracer gas is needed, plus £80 for the gas bottle. If we cannot find it, you are not charged for the time.

24/7Every day, all year
No feeIf we don’t find it
One teamFind, fix, make good
95%Cause found in 400
Leak detection engineer surveying a London property
PinpointedNot guessed. Not dug up.

What the 95% is, and what is in the other five

Every firm quotes a find rate. Ours comes from a tally we actually keep. Across our last 400 leak detection surveys we identified the cause in 95% of them. The remaining 5% is not a shrug, and it is worth knowing what is in it, because that is where the money gets lost.

  • 95%: cause found and pinpointed.
  • 2%: the water was coming from a neighbouring property, so the survey ended in a conversation about access and liability rather than a pipe.
  • 3%: the cause was not plumbing at all, but gutters, roofs and structural defects letting water into the building.

The 3% your insurer will refuse, correctly

That last category is the expensive one to guess at. A buildings policy pays for escape of water, meaning water getting out of a pipe, a tank or an appliance inside the property. Water arriving through a blocked gutter, a failed flashing or a saturated wall is ingress, not escape, and a claim submitted on the wrong basis is declined for good reason. We have opened jobs everyone assumed were burst pipes and closed them on a gutter full of leaves. Establishing which of the two you have, in writing, before anything is submitted is the point of a trace and access report, and it is why our findings state cause and origin rather than “leak located”. If the answer is the roof, you should hear it from us and not from a rejection letter six weeks later.

We are usually not the first company through the door

Much of our work arrives after somebody else has tried. More than once the customer had three separate teams of plumbers through the house before calling us, each unable to locate the leak, each leaving the floor a little more open than they found it. That is what the instruments exist for, and it is the real difference between a plumber and a leak detection specialist: not the trade, the kit and the method.

What a leak costs while nobody can find it

We have attended properties losing over 70 litres an hour. That is 1,680 litres a day, roughly what a dozen people in England get through at the national average of 137 litres each. At Thames Water’s metered rates from 1 April 2026, £2.7346 per cubic metre for clean water and £1.4721 for wastewater, water disappearing at that rate bills out at about £210 a month, more than £2,500 over a year, and it is soaking a structure the whole time it runs. That is the arithmetic behind a bill that jumped for no reason. If yours is running now, call 020 7123 8560.

We work 24 hours a day, seven days a week, across all 32 London boroughs, the City and everywhere inside the M25, so a ceiling that starts dripping at 2am does not wait until Monday. The same £160 an hour covers finding the leak, isolating it and repairing it: one engineer, one rate, with parts and materials costed and agreed before anything is fitted. Attend a confirmed live leak and fail to find it, and the time is not charged.

32

London boroughs covered

Same-day and next-day appointments

4

Methods on every visit

Acoustic, thermal, tracer gas, moisture

No find

no fee

You only pay if we locate the leak

48hr

Insurer-ready reports

Trace & access for your claim

Diagnosis, not demolition

Specialist leak detection finds what guesswork misses

Our job is to find it before the damage spreads, and without turning your home into a building site to do it.

Leak Detection
No find no feeNon-invasive

Leak Detection

Hidden leaks pinpointed without opening floors or walls, acoustic, thermal and tracer gas methods, no find no fee.

Learn more
Thermal Imaging Surveys
InfraredZero disruption

Thermal Imaging Surveys

Infrared cameras reveal wet floors, warm heating runs and moisture spread in minutes, with image evidence included.

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Underground Leaks
CorrelatorsLocate first

Underground Leaks

Supply pipe and mains leaks located under gardens, driveways and concrete, one marked point, one small excavation.

Learn more
Heating & UFH Leaks
Pressure lossUFH loops

Heating & UFH Leaks

Boiler losing pressure? We trace central heating and underfloor heating leaks to centimetres before anything is opened.

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Emergency Plumbing
London and the M25Clear pricing

Emergency Plumbing

Bursts, failed stop taps, blocked toilets and active leaks, urgent response with pricing agreed before we travel.

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Trace & Access Reports
Insurance48h reports

Trace & Access Reports

Insurer-ready documentation of cause, origin and damage, the evidence your escape-of-water claim depends on.

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Before you call anyone

Six signs of a hidden water leak

Most leaks we find were sending one of these signals for months. Two or more together is worth a survey.

A boiler that keeps losing pressure

Topping up the filling loop every few weeks means water is escaping the sealed side, usually a heating pipe or an underfloor loop under the screed.

A water meter that moves with everything off

Note the reading, leave every tap and appliance off for an hour, read it again. Movement is water leaving the system, and it is the single most reliable test you can run yourself.

A bill that rose with no change in usage

A supply pipe leaking underground shows up on the bill long before it shows up on the surface, because the water soaks away into the ground.

Warm patches on a floor

A warm strip across a tiled or wooden floor is a heating pipe losing hot water beneath it, you are feeling the leak, not the pipe run.

A stain that keeps coming back after decorating

Repainted ceilings that yellow again within weeks mean the source was never found. The plaster is being re-wetted from above.

A musty smell with no visible damp

Trapped moisture in a void smells before it shows. By the time a patch appears, water has usually been sitting there for weeks.

Specialist or plumber

What a leak detection specialist does differently

A plumber fixes the pipe. A leak specialist works out which pipe it is, and where, while the floor is still down.

Same trade, different instruments

Every engineer we send is a qualified plumber. The difference is not the trade, it is arriving with correlators, thermal cameras, tracer gas and calibrated moisture meters instead of a torch and a guess.

The floor stays down

A general call-out finds what is visible or audible. When water is under screed or inside a wall, the usual next step is to open something and look. A leak detection specialist narrows a wet ceiling to one pipe before anything is lifted.

Findings written to be accepted

A specialist survey produces cause, origin and moisture readings in the form UK insurers ask for. That paperwork is what turns a trace and access claim into a payment.

Read the longer comparison in leak detection specialist vs plumber, or go straight to home leak detection for flats and houses.

Booking to fixed

Three steps. No surprises.

01

Describe the symptoms

Damp patch, dropping boiler pressure, spinning meter, unexplained bill, the pattern tells us where to start.

02

Fixed rate, quoted first

The hourly rate is fixed before you book and never exceeded. No find, no fee stands on every visit, so a search that finds nothing costs you nothing.

03

Pinpointed, then fixed

We locate the leak to centimetres, repair it on the day where possible, and document everything for your insurer.

Rates, in public

What leak detection costs in London

Every rate below is hourly, quoted before you book, and never exceeded, whatever we find when we arrive. A typical domestic survey runs two to four hours.

£160per hour

Standard leak detection

Acoustic, thermal and moisture testing across a domestic property.

£200per hour

Heating and underfloor

Pressure-loss diagnosis on sealed systems and UFH loops.

£200per hour

Trace and access (insurance)

Survey plus the written report your insurer needs.

£180per hour

Mains water supply

Buried supply pipes under gardens, drives and concrete.

from £175per hour

Moisture mapping survey

Calibrated profiling of how far water has actually travelled.

from £220per hour

Emergency leak detection

Out-of-hours and same-day attendance on active leaks.

Two to four hours at the standard rate puts most domestic leak detection between £320 and £640. If we attend a confirmed live leak and cannot find it, no find no fee means you pay none of it.

Full pricing

Across Greater London

One call, all of London

From inner-city mansion blocks to outer-borough semis, acoustic, thermal and tracer-gas leak detection, and emergency plumbing, wherever you are.

Coverage across all 32 Greater London boroughs and out to the M25. Map data © Google.

Before you book

Leak detection specialist questions, answered

How much does leak detection cost in London?

Detection is charged by the hour at a fixed rate, quoted when you book and never exceeded, whatever we find on arrival, and covered by no find, no fee, so the hours only become a bill if we locate your leak. A standard domestic visit takes two to four hours and includes acoustic, thermal and moisture testing, with tracer gas added for stubborn leaks. Repairs are quoted separately, see our pricing page for current rates.

See current rates

Do you really not charge if you can’t find the leak?

Correct. If we attend a confirmed live leak and fail to locate it, the detection fee is waived. It keeps the incentive honest: we get paid for finding leaks, not for visiting.

Can you fix the leak on the same visit?

Usually. Our detection engineers are qualified plumbers carrying pipe and fittings, so straightforward repairs happen on the day. Larger repairs, buried mains, underfloor heating loops, are quoted precisely once the leak is marked.

Will my insurance pay for this?

Most buildings policies include trace and access cover, which pays for locating a hidden leak and making good the access. Our reports are structured for UK insurers and routinely accepted without a follow-up visit.

How do I find a leak detection specialist near me in London?

Ask three things before you book anyone: whether the rate is hourly and capped, whether no find no fee is genuine, and what equipment is actually coming. A firm charging a low hourly rate with no cap can bill more hours than a capped one and still leave without a result. We quote a fixed hourly rate that is never exceeded, and if we attend a confirmed live leak and cannot locate it, there is no fee. Proximity matters less than it sounds, we hold same-day slots across inner London and reach anywhere inside the M25 the same or next day.

What does a leak detection survey include?

A standard survey starts with the symptoms and the meter, then works through acoustic listening, thermal imaging and calibrated moisture mapping, adding tracer gas where a leak stays stubborn. You get the leak marked to centimetres, photographs of what the cameras and meters showed, and a written summary of cause and origin. Where the claim needs it, that becomes a trace and access report structured for UK insurers.

Which areas do you cover?

All 32 London boroughs, the City of London, and everywhere else inside the M25, which takes in the near parts of Essex, Hertfordshire, Surrey, Kent and Buckinghamshire. Same-day appointments are usually available in inner London, and next-day almost everywhere else.

What should I do if a shower or bathroom is leaking through the ceiling below?

Stop using that shower or bathroom immediately and turn off the water at the isolating valve or stopcock. A stained, bulging or dripping ceiling below a wet room usually means water is escaping from the shower tray seal, waste, or a supply pipe under the floor. Catch drips, move valuables clear, photograph the damage for your insurer, then book a detection visit, we trace whether it is the seal, the waste or a pressurised pipe before anyone opens the ceiling.

Water coming through the ceiling: what to do

Can I ignore a small ceiling water leak, or is it serious?

Never ignore it. Even a small brown patch means water is already sitting in the ceiling void, and plasterboard that stays wet loses strength and can sag or collapse without much warning, sometimes within days if the leak is active, sometimes over weeks with a slow drip. Treat a spreading stain, a soft or bulging area, or drips as urgent. A stain that is dry and unchanged may be historic, but it still needs the source ruled out.

Read the full ceiling leak guide

How can I tell if water is leaking slowly without me knowing?

The reliable checks are your water meter and boiler pressure. Turn off every tap and appliance, note the meter reading, wait an hour and check again, any movement means water is escaping. A combi boiler that keeps losing pressure, an unexplained rise in your bill, warm patches on the floor, a musty smell or faint running-water sound are the other classic signs of a slow hidden leak. Two or more together is a strong prompt to investigate.

Does home insurance cover finding and fixing a leak?

Most UK buildings policies cover sudden escape of water and include trace and access, the cost of locating a hidden leak and making good the floors or walls opened to reach it, with typical caps of £5,000 to £15,000. Gradual leaks, wear and poor maintenance are commonly excluded, and the repair of the failed pipe itself is often your responsibility. Our reports are written to distinguish a sudden failure from gradual wear, which is what keeps a claim payable.

Leak Detection 24/7
020 7123 8560