Water Leak Detection Techniques

When we suspect that the dampness and water damage in your property is being caused by a leak on a concealed pipe we recommend a water leak detection survey is carried out. The leak could be from the central heating pipework, water main, hot or cold supply or waste water pipe.

A 0.5mm hole in a water pipe could lose 20 litres of water every hour, causing considerable damage to your property. It is essential that the leak is located and repaired as soon as possible. In most cases, your home insurance will cover the cost of ‘Trace and Access’, which is the process of locating and exposing the leaking pipe or pipes. Insurance usually does not cover the cost of the repair of the leaking pipe, but it should cover the cost of remedial works to restore the property to its pre loss condition.

We use the following techniques and technology in out leak detection surveys.

Moisture mapping

The first step of our investigation is to produce a moisture map. This allows us to pull together information gathered by a wide range of tools and techniques into a single, clear, guide to the water problem in your home or business. A moisture map will provide a physical, visible, trace of the edge of the water damage.

Electrical Moisture meters

Using safe electrical pulses, these hand-held devices measure the amount of water in a substance. The result will usually be recorded as a percentage. Moisture meters are an easy, non-destructive option, so are a great first choice in many situations. When using a moisture meter, it is important to understand the scale that the individual moisture meter has, as these can vary, and also to recognise that most materials contain some moisture. This means that the ‘dry zone’ may register a low level of moisture on the meter. This is normal, and it’s why a professional will take measurements at various dry points in the property before working to establish the perimeter of the water damage.

Infra-red heat technology (Thermal Imaging)

Thermal imaging is used to locate a leak without disrupting the surrounding environment through the differential measurement of surface temperatures. This method is particularly suited to locating water leaks in central heating and under floor heating pipework.

Tracer gas used to identify escaping water

Tracer Gas is the process of introducing a non-toxic gas mixture into a pipe which does not harm any pipe work and is used to detect leaks on all pipework, including under floor heating systems.

This specialist gas is pressurised through the pipes and makes its way to the surface, where it escapes allowing us to detect your leak with our gas detector. This allows us to locate your leak to a specific area, even under concrete.

Acoustic leak detection

Acoustic leak detection is used to locate leaks using an ultra sensitive microphones, which ‘listen’ for leak sounds that are generated through the damaged pipe work.

The software differentiates between leak generated sounds and background sound contamination.

Correlators can be used to locate leaks on pressurised pipes, where the location of the leak is not known, and the distances are relatively high. Two sensors are placed in contact with the pipe on both sides of the suspected leak. Those sensors record and transmit the sound by radio to the processing unit. Mathematical algorithms are used to determine the exact location of certain noise profiles (such as hissing leak sound) on the pipe, by correlating the noises that reach both sensors and measuring the difference it takes to travel on the pipe from the leak location to each sensor.

Dye testing

Like tracer gas leak analysis, dye testing involves introducing a foreign element into the system and seeing where it comes out. The tester introduces a water-soluble, non-toxic dye into the system and observes its progress. Dye testing can be used in a number of situations, depending on need. It might be used to visually detect a leak as the dyed water is easy to spot.

Salt testing

On-site salt analysis measures the levels of various salts in the water system or ground at different points across the site. The tests detect the presence of chloride and nitrate salts which can be used to determine the likely source of the water ingress. The test takes just a few minutes. A colour change will indicate if certain nitrates and chlorides salts are present which can help identify the source of the leakage. Tap water contains chlorides, rainwater does not, sewerage contains chlorides and nitrates where ground water only contains nitrates.

In most cases we can excavate and repair the leak on the day of the survey. The cost of the excavation and repair will depend on the location and nature of the leaking pipework. We will provide a quotation of any excavation and repair works prior to carrying them out.

In some cases, the presence of possible asbestos containing materials (ACM) such as thermoplastic tiles and tile adhesive, may prevent excavation works until the substance has been tested. If you have an asbestos register for the property please provide this information to us prior to the survey. Alternatively, we can arrange for the sampling and testing of any suspect materials to determine the presence of asbestos.

Please confirm the location of your internal and external water main stock cock prior to our arrival and if possible, check that they are functioning correctly. If the external stop cock is on a shared main it may not be possible to carry out full assessment without shutting off internal isolation valves in all properties on the shared main. If this is not possible a new external stopcock may be needed in order to isolate the mains water feed to your property and an additional survey visit may be required.

In properties where there is central heating and/or underfloor heating systems present, please have these running for 1 hour prior to our arrival to ensure that thermal imaging assessment can be carried out.

Biocraft offers a wide range of water leak detection and surveys in Reading and throughout Berkshire, Hampshire, Surrey and Oxfordshire. For a professional and reliable assessment, please call us on 0118 943 2111 or email [email protected].