How does concealed leak detection work?

The damp patch shows where water has arrived. To find where it escaped, an engineer checks the pipework, follows the evidence and compares results from the methods that suit your property.

Need help finding a hidden leak?

Call 0333 567 2641

Monday to Friday, 7:30am to 6:30pm. The office will tell you which methods suit your leak.

4.7 Excellent on Trustpilot from 1,620 reviews of ADI Leak Detection

Start with the symptoms

A moving water meter, falling boiler pressure and a damp ceiling point to different investigations. The engineer asks when the problem started, checks accessible fittings and works out which water or heating circuit could be involved. Condensation, rainwater and an overflowing appliance can also leave damp patches.

Check which pipe or circuit is losing water

Where the system allows it, individual sections can be isolated and pressure tested. This helps separate a supply pipe problem from internal plumbing, or one heating loop from another. Pressure loss needs interpreting alongside the condition of valves and test connections.

Follow the route and the spread of water

Moisture readings help map the affected wall or floor. A thermal camera records surface temperature differences, which can help trace warm pipe routes and areas affected by moisture. Neither instrument can see through a wall or identify every leak on its own.

Narrow the search with suitable detection methods

A ground microphone can pick up the noise of a pressurised leak beneath a floor or drive. If the leak is too quiet, or the pipe carries little sound, tracer gas testing may provide another clue. Gas introduced into suitable isolated pipework can escape at the defect and be detected at the surface. Access, floor construction and the route the gas takes affect the result.

A borescope can help inspect an accessible void through an existing opening or an agreed small access hole. The equipment guide explains what each instrument contributes.

Compare the evidence before opening up

Water can travel along a joist or beneath tiles before it becomes visible. Engineers compare the suspected pipe route, moisture pattern and detection readings to select the area to investigate. Further tests may be needed when the results disagree.

Discuss access, repair and the report

Locating a concealed leak aims to reduce exploratory damage. Repair will usually need access to the pipe, and the size of the opening depends on the construction and the work required. Discuss the proposed access and repair with the engineer before work starts. ADI provides a report of the investigation and findings, with photographs, which you can share with your insurer.

Customers who watched it done

“…used thermal imaging cameras, sensors, and specialised water detection equipment to locate the leak…”

Eunice, Trustpilot review, 2 March 2025

“…he managed to trace the leak to a small hidden space under the stairs.”

Stephen B., Trustpilot review, 19 February 2023

“No visible signs of where the leak was so called ADI.”

Nigel P., Trustpilot review, 18 December 2025

Read ADI customer reviews

Common questions

Why use more than one leak detection method?

Moisture can spread away from a leak, sound can travel along pipes, and tracer gas can emerge through an easier path in the floor. Comparing test results helps the engineer interpret those clues and select an area to investigate.

Can a concealed leak be found without damaging the floor or wall?

Many checks can be made from the surface or at accessible fittings. The aim is to reduce exploratory opening, but an inspection hole may still be needed and repairing a concealed pipe usually requires access. The engineer should discuss proposed access before work begins.

Will I get a report for my insurer?

ADI provides a report of the tests and findings, with photographs, which you can share with your insurer. Check any requirements with your insurer before authorising work; a report does not establish that your policy covers the cost.

Call 0333 567 2641

Mon to Fri, 7:30am to 6:30pm