The Leak Detection Survey, Step by Step

The survey starts with a conversation about what you have noticed and when, followed by a look at the meter with every tap and appliance off. If the meter moves, water is escaping on your side of it. A test strip on any water we can reach tells us whether it is mains, heating or waste water. Each system is then pressure tested in turn: the cold mains, the hot water, the heating circuit and, where there is underfloor heating, each loop at the manifold. By the end of this stage we usually know which system is leaking, and the search narrows from the whole property to one pipe run.

Then the locating kit comes out, in the order the pipe run calls for. The thermal camera goes over floors, walls and ceilings along the suspect run, with the heating on for warm pipes. The acoustic ground microphone follows on mains-pressure pipes, and tracer gas goes into any drained section that is plastic, buried or silent. Bathrooms get a dye test in the bath, shower tray and basin so a failed seal or waste is not mistaken for a pipe leak. A borescope is pushed into voids through existing gaps. The leak is then marked on the surface and photographed.

Most home surveys take between two and four hours, and we say before the visit if the property or the symptoms suggest longer. To prepare, have the heating on and know where the stop tap is. Clear access to the boiler, the meter, the airing cupboard and any manifold, and gather any photographs of the problem over time. The report follows, with the systems tested, the methods used, the readings, thermal images, photographs and the marked location. If nothing is found, the report still records what was ruled out, which is itself useful evidence.