About us
How a leak gets established rather than guessed
London Leak Detection 247 is a survey led practice. Most of the properties we are called to have already had someone look at them, and the reason the leak is still there is almost never a lack of effort. It is that nobody eliminated the systems in order, so every opinion since has been a guess with a confident voice.
The work, described plainly
We survey buildings to establish where water is escaping and to prove it well enough that somebody can be asked to pay for the repair. The instruments are acoustic correlators and ground microphones, thermal cameras, a 5% hydrogen tracer gas rig, calibrated moisture meters and per circuit pressure test equipment. None of them is the answer on its own, which is the whole point of carrying all of them.
Our engineers hold plumbing qualifications as well, so where the finding is straightforward and access allows, the repair can follow in the same visit. That is a convenience, not the business model. The diagnosis is what you are buying, and it has to stand up whether we do the repair or your own contractor does.
Coverage runs across all 33 London boroughs. The borough pages on this site set out the housing stock in each one and how it tends to fail, because the construction is what decides the method, and knowing it before we load the van is part of doing the job properly.
Who instructs us
- Landlords with a tenant reporting damp and a plumber who found nothing
- Freeholders deciding whether a riser or a demised pipe is at fault
- Managing agents needing an independent finding before a service charge argument
- Leaseholders with water arriving from a flat that denies having a leak
- Surveyors wanting an instrumented second opinion on a moisture reading
- Owner occupiers whose boiler keeps losing pressure for no visible reason
The chain of evidence
Every survey runs the same five links in the same order. Skipping one is how firms end up marking a floor they cannot defend.
01. Symptom is described, not diagnosed
What the meter does with the stop tap closed, what the boiler pressure does overnight, where the staining sits relative to the room above. We take the observations and leave the conclusion open, because a symptom that everyone has already agreed is "the bathroom waste" is the one nobody re-tests.
02. Systems are eliminated one at a time
Heating circuits, hot and cold supply, the incoming main and the boiler itself are isolated and pressure tested separately. Testing the whole property as one lump tells you a leak exists. Testing circuit by circuit tells you which one, and that is the difference between a survey and a shrug.
03. Method is chosen by material, not by habit
Copper and steel carry leak noise, so acoustic correlation is the first reach. Plastic and PEX absorb it, so the job moves to tracer gas. A hot pressurised run under screed reads well on thermal. Every operator has a favourite instrument; the building is supposed to pick it, not the operator.
04. Nothing is signed off on one reading
A thermal anomaly is a temperature, not a leak. A moisture peak is where water surfaced, which under screed can be metres from where it left the pipe. Before we mark a point we corroborate it with a second, independent method, and if the two disagree we keep working rather than average them.
05. The finding is written down properly
Cause and origin, the method that established each, moisture readings by room with the scale named, photographs keyed to the marked point, and the scope of opening up a contractor would need. Written so that someone who was not there can rely on it, because usually they were not.
Where we draw the lines
We do not open anything speculatively
Lifting a floor to see what is under it is not detection, it is demolition with optimism attached. If our instruments cannot narrow the point, we say so and the detection fee is waived rather than converted into exploratory joinery.
We separate the finding from the repair
The survey is quoted and settled on its own, and you are welcome to take the report to your own contractor. A firm that only gets paid when it finds something expensive has a reason to find something expensive, and that is a structural problem, not a character one.
We report findings that do not suit the client
Plenty of surveys end with the leak sitting in the party who commissioned us. Condensation misread as a leak, a shower tray seal rather than a pipe, a boiler component rather than the flat upstairs. We write what the instruments said, which is the only reason the report is worth anything in a dispute.
We name the limits of what we measured
Where a circuit could not be isolated, where access blocked a scan, where a reading was taken through a finish that affects it. A report that pretends to certainty it does not have gets picked apart the first time someone challenges it.
Send us what has already been ruled out
Previous plumber reports, meter behaviour, boiler pressure history. Knowing what has been tested already is how we avoid charging you to repeat it.
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