Water Leak Detection in London
Clear Flow locates hidden water leaks across every London borough using non-invasive thermal imaging, tracer gas, and acoustic detection — no drilling, no lifted floorboards, no guesswork. We identify the exact source before recommending any access work. Same-day appointments available.
What Does Professional Leak Detection Involve?
We are detection specialists, not plumbers. The difference matters: we assess first, select the right instrument for your building and pipe type, identify the precise source, and only then recommend any access work — if it is needed at all.
Water leak tracing requires calibrated equipment matched to the substrate. A thermal camera will not see through dense concrete; a tracer gas probe will. An acoustic correlator can triangulate a mains pipe escape through tarmac; a moisture meter maps the spread after the source is found. We carry every tool and deploy the combination that suits your specific situation — not the first one to hand.
Every investigation ends with a written survey report: annotated photographs, the confirmed leak location, and recommended next steps. That report is accepted by all major UK home insurers for Trace & Access claims and can be submitted directly to your loss adjuster.
Our six detection methods:
Types of Water Leak We Locate Across London
Hidden leaks present differently depending on pipe type, building construction, and how long the problem has been developing. These are the scenarios our London teams are called to most often.
Underfloor Heating Leaks
Pressurised UFH circuits lose water slowly — symptoms are cold patches in the floor, falling system pressure, and energy bills that don't match usage. Tracer gas is the primary detection method, accurate to within centimetres through concrete and screed without lifting a single tile.
Central Heating System Leaks
Pinhole corrosion in a sealed heating system causes slow pressure loss that is impossible to trace visually. We isolate each circuit, test under pressure, and narrow the escape point to a specific pipe run or fitting before any access work is considered.
Mains Water Supply Leaks
A concealed supply pipe losing pressure raises bills, saturates ground-floor construction, and can undermine foundations silently for months. We locate the escape point and produce a report suitable for Thames Water enquiries and home insurance submissions.
Ceiling & Inter-Floor Leaks
Water appearing at a ceiling rarely originates directly above — it travels along joists and pipe runs before emerging. Thermal imaging maps the spread and pinpoints the source without disturbing the ceiling or the floor above.
Trace & Access Insurance Claims
If your home insurance includes Trace & Access cover, your insurer pays for both the detection survey and reinstating any surfaces opened. We produce the report your insurer requires and can liaise directly with your loss adjuster.
Flat Roof, Drain & Boiler Leaks
From soil pipe failures and flat roof waterproofing breaches to boiler connection drips and waste pipe corrosion — our engineers carry the full range of diagnostic tools for every leak scenario a London property presents.
Leak Detection Across All 32 London Boroughs
Clear Flow covers every London borough — from Barnet and Enfield in the north to Croydon and Bromley in the south. We also operate across Surrey and Kent. If you are unsure whether we cover your postcode, call us and we will confirm immediately.
North London
Victorian terrace plumbing, new builds in Barnet, converted flats throughout Islington and Camden — our North London teams cover all construction types.
East London
From period properties in Hackney to large residential estates in Newham, acoustic and tracer gas detection works through any substrate our East London teams encounter.
South & South-East London
Covering Bromley, Croydon and the South-East corridor through to the Kent boundary — same-day availability and the same detection standards throughout.
South-West London
From converted Victorian stock in Lambeth and Wandsworth to riverside properties in Richmond and Kingston — we cover the full South-West.
West & Central London
High-value period and new-build properties across Kensington, Westminster, Brent, and the City — discreet, insurance-ready, no unnecessary disruption.
Surrey & Kent
Our South-East coverage extends beyond the M25 into Surrey and Kent — Guildford, Woking, Epsom, Reigate, Sevenoaks, and Tunbridge Wells.
Why London Property Owners Choose Clear Flow
Most leak detection companies carry one or two methods. We carry six, and we match the right combination to your specific situation for a faster, more accurate result.
Book a Survey- Same-day appointments
Most London bookings are attended and completed within 24 hours of your call.
- Six detection methods
We select the right combination for your specific pipe type and building construction — not the first tool available.
- No access work until confirmed
We do not open a wall or lift a floor until the exact leak point is identified and agreed with you.
- Insurance-approved written reports
Annotated photographs and full survey findings — accepted by all major UK home insurers for Trace & Access claims.
- DBS-checked, directly employed engineers
No subcontractors. Every engineer on your property is vetted, employed, and trained to the same standard.
- All 32 London boroughs, Surrey & Kent
One company, complete coverage. No area surcharges within our standard service zone.
Trusted Across London
Absolutely quality service and what plumbers should exemplify. Turned up when they said, was kind, answered all my questions and wasn't being dodgy with anything. Skilful and efficient! Would highly recommend.
The technician arrived on time, was polite, and explained the process clearly before starting. They used advanced, non-invasive equipment to locate the leak quickly without causing any unnecessary damage to my property.
Really impressed with the service. They responded quickly and were able to accurately detect the leak without causing unnecessary damage. Professional, efficient, and clearly experienced — would highly recommend to anyone dealing with a hidden leak.
Wayne and his colleague came and within an hour found the leak deep underneath my cellar and came up with a perfect plan which made the pipe redundant and re-routed it the following morning. An excellent option if you're having a problem with a leak you cannot find.
Called Wayne Monday and he was round Tuesday evening — came out of hours to help me out. Very professional, punctual and great with communication. Fair priced too. Will definitely recommend and use again.
Contacted them and they were at the property within an hour. Honest, well priced and gave a detailed report that will likely save me hundreds of pounds. Will definitely recommend and if necessary will use again.
Wonderful efficient service — came out the same day, nothing was too much trouble. Engineers were professional and polite, explained the problem and persevered until the blockage was cleared. Would highly recommend this company.
The staff were so professional and friendly. The technician was nice and informative — he advised me the leak was outside and wrote me a report which I sent to Thames Water. In a few days they sent a repair team and found the leak. Clear Flow are great at what they do.
I received a letter from Thames Water about high water usage. Wayne arrived on time, was so professional, guided me through what he was doing and advised me of the next steps. He also wrote me a report to send to the water board. 100% recommend.
Leak Detection in London — Common Questions
Not sure what to expect, or whether your situation qualifies? These are the questions our London customers ask most often.
How much does leak detection cost in London?
The cost depends on property size, number of pipe circuits to test, and which detection methods are required. We provide a fixed price before any work begins — no call-out charges added after the fact. Most domestic investigations are priced as a single fixed fee with no hidden additions. Contact us for a quote specific to your situation.
Do you offer same-day or emergency leak detection in London?
Yes. We offer same-day appointments across all London boroughs and operate a 24-hour call-out service for urgent situations including visible flooding or active mains leaks. Call us directly and our team will prioritise your booking. Most London jobs are attended within a few hours of your call.
What is the most accurate method for finding a hidden water leak?
It depends on the pipe type and building construction. Tracer gas is typically the most precise — accurate to within a few centimetres through concrete, screed, and soil. For ceiling leaks and inter-floor issues, thermal imaging usually gives the clearest result. In most investigations we combine two methods independently to cross-confirm the source before marking the access point.
Is leak detection covered by home insurance?
Many home insurance policies include Trace & Access cover, which pays for both the detection survey and reinstating any surfaces opened during the investigation. We produce the survey report your insurer requires and can liaise with your loss adjuster directly. If you are unsure whether your policy includes this cover, call your insurer before booking — we can advise on the documentation they will need.
Do you need to lift floors or open walls to find the leak?
No. Our detection methods — thermal imaging, tracer gas, and acoustic sensors — work entirely from the surface. We do not open walls, lift floors, or break tiles during the investigation. Any access work only happens after the exact leak point is confirmed and agreed with you, and only to the minimum extent required for the repair.
How long does a leak detection survey take in London?
Most domestic properties take one to three hours on-site. More complex situations — larger properties, multiple pipe circuits, or restricted access — may take longer. We give you an estimated duration when you book, along with a clear fixed price.
Which London boroughs do you cover?
We cover all 32 London boroughs, from Barnet and Enfield in the north to Croydon and Bromley in the south, including the City of London, East and West London, and all inner London areas. We also serve parts of Surrey and Kent. If you are unsure about your specific postcode, call us — our team can confirm immediately.
What happens after you find the leak?
We issue a written survey report with the confirmed leak location, annotated photographs, and recommended next steps. For most domestic leaks our engineers can carry out the repair on the same visit. Where structural drying, specialist reinstatement, or insurance coordination is required, we work with trusted contractors and manage the process end to end.
What is the difference between leak detection and trace and access?
Trace and access is the insurance industry term for locating a hidden leak (the "trace") and reinstating any building fabric opened to access the pipe (the "access"). Leak detection refers specifically to the investigative phase — finding the source. If your home insurance includes Trace & Access cover, it pays for both the detection survey and the making-good work. We handle both.
GOT A LEAK?
WE'RE READY.
Same-day and emergency appointments available across London and the South East. Most leaks found and fixed in a single visit.