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Mr Leak

24 hours a day, 7 days a week · 1 hour response target

We find the leak.
Not the whole floor.

Leak detection specialists for Sussex, Surrey and London. Thermal imaging, acoustic correlation and tracer gas locate hidden water leaks to the exact point — before anyone lifts a floorboard or opens a wall. Same-day response, and a report your insurer will accept.

Find it, fix it, stop the damage.

No call-out fee · No emergency surcharge · From £54.00 + VAT · 12-month workmanship guarantee

Survey in progressLive
  • 01Thermal imagingΔ −4.8 °C at ceiling void
  • 02Acoustic correlationPeak at 742 Hz, joist 4
  • 03Moisture mapping98% WME over 380 mm
  • 04Tracer gasH₂ confirmed at joint

Source located

Compression joint · 1.4 m from the stain

01 · Day one

A joint starts to weep

A compression joint on a heating pipe in the floor void begins to seep — a few millilitres an hour. Nothing is visible in either room. Nothing is audible. The only record anywhere is a boiler that needs topping up slightly more often than it used to.

Loss rate
0.6 l / hr
Visible signs
None
Time undetected
11 weeks
Scroll to follow the leak

What we do

Every kind of leak, and the proof to go with it

From a weeping heating joint under a screed floor to a mains supply pipe under a driveway, and the trace-and-access report that gets it paid for.

All services

How we find it

Ten ways to find water without breaking anything

No single instrument finds every leak. We arrive with all of them and work through the property system by system until the evidence agrees.

  • 01

    Thermal imaging camera survey

    A radiometric camera reads surface temperature through plaster, screed and tile to reveal the cold plume of an escaping supply pipe or the warm track of a heating leak.

  • 02

    Acoustic leak correlation

    Ground microphones and digital correlators listen for the specific hiss of pressurised water forcing its way out of a pipe, then triangulate the exact point.

  • 03

    Tracer gas testing

    A harmless hydrogen and nitrogen mix is introduced into drained pipework, escapes at the fault, and is picked up at the surface by a gas sensor.

  • 04

    Moisture mapping and salts analysis

    Pin and pinless meters chart how wet a structure is, and a salts test tells us whether the water arrived from a pipe, from the ground, or from the weather.

  • 05

    Pressure and flow testing

    Isolating and pressurising each circuit in turn proves which one is losing water, and how fast, before anything is opened up.

  • 06

    CCTV drainage survey

    A self-levelling camera crawls the drain run and records exactly what is broken, where it is, and how deep.

  • 07

    Borescope inspection

    A camera on a flexible probe goes through a hole the size of a pencil to look inside a void, wall or ceiling.

  • 08

    Tracer dye testing

    Non-staining fluorescent dye is added to one water source at a time so the escaping water carries a colour-coded label.

  • 09

    Pipe and cable tracing

    A signal generator puts a tone on the pipe and a receiver follows it, so we map the route and depth before anyone digs.

  • 10

    Roof integrity and voltage testing

    Low-voltage electronic testing finds breaches in a flat-roof membrane that are invisible from the surface.

Why Mr Leak

Straight answers, published prices, evidence you can hand over

Leak detection attracts guesswork, because guessing is cheap and the customer rarely finds out until the floor is already up. We work the other way round: non-invasive methods first, a specific location rather than a probable one, and a written record of how we proved it.

Our rates are on the website rather than quoted on the doorstep. There is no call-out fee and no emergency surcharge, and if the job is going to run longer than expected we tell you on site rather than letting the clock run.

£54.00
From, per half hour + VAT
1 hour
Response time target
24/7
Emergency line, no surcharge
12 mo
Workmanship guarantee

What it costs

Charged by the half hour, half an hour minimum. No call-out fee.

  • Weekdays7am – 6pm, Monday to Friday£54.00+ VAT
  • Evenings & weekends6pm – 9pm weekdays, plus all day Saturday and Sunday£69.75+ VAT
  • Late night9pm – 7am, every day£90.00+ VAT

5% off 4 hours or more · 10% off 8 hours or more. All prices exclude VAT at 20%.

Insurance claims

Your policy almost certainly pays for this

Trace and access cover is in nearly every UK buildings policy. It pays for finding the leak and for the damage caused by getting to it — and most people never claim it, because they do not know it is there.

  • Calibrated moisture readings and dated photographic evidence
  • A stated methodology, so a loss adjuster can follow the reasoning
  • A clear causation finding: escape of water, damp, or weather ingress
  • A schedule of access and reinstatement costs

Leak detection report

Escape of water — findings

Resolved
Cause
Failed olive, 15 mm compression joint
Location
First floor void, joist 4, +742 mm from party wall
Method
Thermal imaging, acoustic correlation, tracer gas
Moisture before
98% WME across 380 mm
Moisture after drying
14% WME
Pressure test
Held 1.5 bar for 30 minutes

Where we work

74 towns, cities and boroughs

Engineers based in Brighton and working across Sussex, Surrey and every London borough. Pick your area to see what we typically find in the housing stock near you.

All areas

Leak detection in Sussex

Our home patch. From our Brighton base we cover the coastal strip from Littlehampton to Eastbourne and inland through the Mid Sussex towns, with a one hour response target across the county.

Leak detection in Surrey

Centred on Dorking and reaching from the Mole Valley across to Guildford, Woking and the Thames-side towns, covering the whole of east and mid Surrey.

Leak detection in London

All 32 London boroughs plus the City, covered by engineers working across the capital seven days a week, including overnight attendance for commercial and managed properties.

Questions

The things people ask before they call

How much does leak detection cost?

Weekday surveys start at £54.00 + VAT with a half-hour minimum charge, and there is no call-out fee. Evenings and weekends start at £69.75 + VAT and late nights at £90.00 + VAT. Longer jobs are discounted: 5% off from four hours and 10% off from eight. Most domestic leaks are found within one to three hours.

Will my home insurance pay for leak detection?

Usually, yes. Almost every UK buildings policy includes trace and access cover, which pays for finding the source of an escape of water and for the damage caused by getting to it. Our reports are written to the standard loss adjusters work to, and we invoice so the cost can be submitted with your claim.

How quickly can you get to me?

We answer the phone 24 hours a day, 7 days a week and target a 1 hour response across Sussex, Surrey and London. There is no surcharge for an emergency, though the hourly rate does vary by time of day.

Will you damage my property to find the leak?

No. Thermal imaging, acoustic correlation, tracer gas and moisture mapping are all non-invasive, and we use them first as a matter of course. An opening is only made once the evidence points at one specific place, and it is normally small enough to fill and touch in.

How do I know if I have a hidden water leak?

The reliable test is your water meter. Turn off every tap and appliance, note the reading, and check it again after two hours with nothing used. If it has moved, water is escaping somewhere. Other common signs are a rising bill with no change in usage, a boiler that keeps losing pressure, a warm or cold patch on a floor, a musty smell, or the sound of running water when everything is off.

Can you repair the leak once you have found it?

Yes. Our engineers carry repair materials, so most leaks are fixed on the same visit as the survey and then pressure tested before we leave. Workmanship is guaranteed for 12 months, and any larger works are quoted at a fixed price before starting.

Do you cover my area?

We cover the whole of Sussex from Littlehampton to Eastbourne and inland through Mid Sussex, all of east and mid Surrey from our Dorking coverage, and every one of the 32 London boroughs plus the City. If you are not sure, call and ask — we will tell you straight away.

What is the difference between damp and a leak?

A leak is clean water escaping from a pipe or the building envelope. Rising damp is ground moisture drawn up through the fabric, and condensation is airborne moisture settling on a cold surface. They look almost identical on a wall, but only escape of water is normally covered by insurance, and each needs a completely different remedy. A salts test on a plaster sample tells them apart in one visit.

Do I need to be at home for the survey?

Someone over 18 needs to give us access and be there while we work, and it helps enormously if that person knows the history — when it started, what has been done already, and where the stop tap is. For managed blocks and commercial sites we can work with a key holder or agent instead.

What should I do right now if water is coming through my ceiling?

Turn the water off at the internal stop tap, and turn off the electricity at the consumer unit if water is anywhere near lights or sockets. Keep out from under a bulging ceiling. Photograph everything before you move it, because your insurer will ask. Then call us.

Think you have a leak? Let us find it.

Non-invasive survey, same-day response and a written report your insurer will accept. No call-out fee, and no charge for advice over the phone.