Pre-Purchase Leak Survey

Most surveyors are clear about what they do not do. A homebuyer report will note damp readings and visible staining, but the pipework is usually described as not tested, and the heating as not tested or only switched on briefly. Hidden leaks sit squarely in that gap. A supply pipe losing water under the front garden or a heating circuit slowly dropping pressure may show nothing on the day of a viewing. The same goes for an underfloor heating loop leaking into a screed. The seller may not know either. Finding it after completion means you own the problem and the cost.

The leak survey covers the parts the building survey leaves out. We read the meter with every outlet off and pressure test the cold mains, the hot water and the heating circuit. Each underfloor heating loop is isolated at the manifold and tested on its own. The heating runs while the thermal camera goes over floors and walls, and moisture readings are taken at suspect areas and around bathrooms. Baths, showers and basins get a dye test. Where something looks wrong, the acoustic microphone or tracer gas is used to locate it, so the report says where the problem is, not just that there is one.

Timing matters. The survey needs the seller or agent to allow access for a few hours with the water and heating on. It is best done after your offer is accepted and before exchange, when the findings can still affect the price or the conditions. The report sets out the systems tested, the results, the readings and the thermal images in plain language, so your solicitor or the agent can pass it to the seller without interpretation. It can be used to ask for the repair to be done before completion or for an adjustment to the price.