Specialist Leak Detection
Leak Detection Specialists
in London, Non-Invasive
Advanced thermal imaging, acoustic detection, and tracer gas technology. We pinpoint hidden leaks across all 32 London boroughs and the City without causing damage to your property. No find, no fee.
Covering EC, E, N, NW, SE, SW, W postcodes across all 32 London boroughs and the City
Call 020 3912 0200Contact Us
Tell us about your leak and we'll get back to you with a free, no-obligation quote. For an active leak, ring us now.
How We Work
What We Do
Specialist Leak Detection Services
Water Leak Detection
Unexplained damp patches, rising water bills, or the sound of running water? Our specialist equipment locates hidden leaks without damage to your property.
Heating Leak Detection
Boiler losing pressure? Underfloor heating not performing? We pinpoint leaks in central heating, underfloor circuits, and radiator pipework.
Insurance Trace & Access
Full trace and access investigations with insurer-approved reports, thermal imaging evidence, and moisture readings. We liaise directly with your loss adjuster.
Why Choose Us
Specialist vs General Plumber
Most plumbers guess where the leak is and start digging. We use advanced technology to find it first - saving you time, money, and your property.
The Old Way
General plumber approach
Our Way
Specialist leak detection
Active Leak?
Every minute counts. Call now and speak to our detection team, day or night.
020 3912 0200Not Urgent?
Book a scheduled detection survey at a time that works for you.
Book OnlineThree Simple Steps
How Our Leak Detection Works
You Call Us
Ring us or fill in the form. Describe what you're experiencing and we'll advise on the best approach - same-day visits available.
We Detect
A specialist arrives with thermal imaging, acoustic, and tracer gas equipment. We pinpoint the leak without unnecessary damage.
You Get a Report
You receive a clear report showing exactly where the leak is. We can repair it on the same visit in most cases, or provide a detailed quote.
What Non-Invasive Leak Detection Actually Means
Non-invasive leak detection means finding the leak before anything is opened up, rather than opening things up in order to find it. The distinction matters because the damage done searching for a leak is often worse than the damage the leak has caused. A plumber without detection equipment has one honest method available: lift the floor where the damp is worst and work outwards. That is frequently the wrong place, because water travels along joists and under screed and surfaces a long way from where it escaped.
Non-invasive detection uses instruments instead. Acoustic sensors listen for the escape, thermal cameras read temperature differences through the floor surface, moisture meters map how wet the structure is and where that wetness ends, and tracer gas is introduced into the isolated pipe and picked up at the surface where it rises. Nothing is cut until the position is known, and then only at that position.
This is also the sense in which the trade uses electronic leak detection. It is not a single machine and it is not a guarantee. It is the same idea named after the instruments, and the question that decides whether it works on your leak is whether the method chosen can reach it. Acoustic equipment is electronic and still struggles on a plastic pipe under deep screed. Anyone selling the label rather than the survey is worth a second question.
What non-invasive does not mean is that nothing is ever opened. Reaching a leak to repair it usually requires access. It means the opening is one small area chosen on evidence, instead of a room taken apart on a guess.
Six Signs You Have a Hidden Water Leak
No single symptom proves a hidden leak. Two or three together usually do, and most of these cost nothing to check before you call anyone.
The water meter moves with everything turned off
The most reliable test there is. Close every tap and appliance, read the meter, wait thirty minutes without using any water, read it again. Movement means water is escaping somewhere between the meter and your taps.
The boiler keeps needing topping up
A sealed heating system holds its pressure for months. Topping up more than two or three times a year means the system is losing water, and buried heating pipes are one of the places it goes.
A patch of floor is warm for no reason
Where there is no underfloor heating, a warm stripe or patch usually means a hot water pipe below is leaking and heating the screed around it.
The water bill rose and nothing else changed
Compare like quarters rather than consecutive ones. An unexplained rise of twenty per cent or more on the same household usage is worth investigating before the next bill.
A musty smell with no visible damp
Water trapped under a floor or behind a wall smells long before it shows. If a room smells damp and looks dry, something behind the surface is wet.
A stain that grows whether or not it rains
Timing is the tell. A mark that darkens after rain and dries back between downpours is usually the building fabric. One that spreads steadily in dry weather is usually plumbing.
Which Leak Detection Method Your Leak Needs
The survey is a diagnosis, and the diagnosis starts with which system is losing water. That is usually readable from the symptom before anyone arrives. Every van carries all of the equipment below, so the method is chosen on site rather than sold in advance, and where the first one is inconclusive we move to the next in the same visit.
| What you are seeing | The survey it points to | Why that one |
|---|---|---|
| A damp patch on a wall, ceiling or solid floor, mains still under pressure | Acoustic leak detection | A pressurised pipe leaking into the structure makes a continuous noise. Ground microphones and a correlator find where it is loudest. |
| A warm patch underfoot, or one heating zone that will not hold pressure | Thermal imaging leak detection | Infrared shows the buried pipe runs through the floor surface, and a leak reads as a bloom of heat the wrong shape for a pipe. |
| The meter creeps with the internal stopcock closed | Water mains leak detection | The loss is on the buried supply pipe outside. Correlation and tracer gas locate it under a drive without lifting the whole run. |
| Boiler pressure falls and no water is visible anywhere | Central heating leak detection | The circuits are isolated and tested separately, which rules the boiler and its expansion vessel in or out before any floor is touched. |
| A stain that reacts to the weather rather than to water use | Damp and mould survey | Frequently not plumbing at all. Moisture mapping separates a leak from condensation or penetrating damp before anyone pays for the wrong repair. |
| An insurer or loss adjuster has asked for evidence | Trace and access survey | The same investigation, written up as the report a claim is decided on, with readings, images and a conclusion on cause. |
Not sure which line is yours? Call 020 3912 0200 and describe what you can see. You will be told which survey it is and what it costs before anything is booked.
Transparent Pricing
Clear Pricing, No Hidden Fees
We agree the price before any work begins. No surprises, no extras. Here's what London homeowners typically pay.
Standard Leak Detection
Thermal imaging, acoustic detection, and moisture mapping. Fixed price agreed before we start
Heating Leak Detection
Central heating and underfloor heating systems. Pressure testing and thermal imaging included
Trace & Access (Insurance)
Full investigation with insurer-approved report, photos, and moisture readings
Mains Water Leak Detection
Acoustic and tracer gas methods to locate supply pipe leaks with minimal excavation
Moisture Mapping Survey
Comprehensive moisture survey with detailed report. Ideal for damp investigations
Emergency Leak Detection
24/7 emergency response. Same equipment and expertise, available any time day or night
No Find, No Fee Guarantee
If we can't locate the leak, you don't pay for the detection. Repair costs are quoted separately if needed. Many straightforward repairs can be completed on the same visit.
Average London leak detection: \u00a3300–\u00a3600. Our prices include the full report.
Case Studies
Recent Detection Jobs Across London
Taken from our engineers' reports, with their own photos from the day.
7 litres a minute lost under a suspended timber floor
The gas reading concentrated at one spot, and the floor there had visibly sunk compared with the boards around it. No comparable reading anywhere else in the property.
Read the job →
25 litres an hour from old underground pipe in a church hall
Old imperial-sized plastic supply pipe running underground beneath the main hall, with heavy gas escaping where it joins a stopcock. With the water turned back on, the leak was seen running from that joint.
Read the job →
Boiler losing pressure straight after every top-up, and no leak
No leak anywhere in the heating pipework. The pressure loss was water leaving through the boiler's pressure relief valve, consistent with a failed expansion vessel.
Read the job →
Part of the Emergency Repairs London Group
Specialist Leak Detection Backed by London's Trusted Home Services Provider
Leak Detect London is the dedicated leak detection arm of Emergency Repairs London, a 24/7 home repairs company in London. Leak Detect London focuses on one job: finding hidden leaks, water damage and damp without tearing the property apart.
We invested in the best leak detection technology available - thermal imaging cameras, acoustic listening equipment, tracer gas systems, and moisture mapping tools - so we can find leaks non-invasively and save our customers from unnecessary damage and cost.
Whether you're in Westminster or Wandsworth, Hackney or Hounslow, you get engineers who use the same non-invasive methods and write up every survey in a clear report.
We've also expanded into South Yorkshire – visit Emergency Repairs Doncaster for 24/7 plumbing and repairs across Doncaster.
Free Quote
Get a No-Obligation Leak Detection Quote
Tell us what's happening and we'll come back to you with a clear price for the investigation. No pressure, no hidden fees. Or if it's urgent, just ring us. We pick up 24/7.
Prefer to talk? Call 020 3912 0200Service Area
All 32 London Boroughs + the City
Our leak detection specialists are based across London. We reach every borough listed below, and we also cover areas within the M25.
Give us a ring with your postcode. We cover more than what's listed and can usually confirm in seconds.
020 3912 0200All London Boroughs
Specialist Leak Detection Across All 32 Boroughs + the City
From central London to the outer boroughs, our engineers are on call 24/7 to locate and resolve hidden leaks.
Expert Guides
Practical advice from our London leak detection specialists.
Boiler Keeps Losing Pressure but No Visible Leak? How to Find Where the Water Is Going
11 min read
How Thermal Imaging Finds Hidden Water Leaks
Trace and Access Cover Explained: What It Is and What It Costs
Underfloor Heating Losing Pressure? The Checks That Find the Leaking Loop
Underground Water Leak Detection: Finding a Leak on Your Supply Pipe
Water Coming Through the Ceiling: What to Do in the First Hour
FAQ
Frequently Asked Questions
Got a question not answered here? Call us on 020 3912 0200 - we're available 24/7.