Signs you need acoustic leak detection
Most people who end up with an acoustic survey have noticed one of these:
- The water meter keeps moving with every tap, toilet and appliance turned off.
- The water company has written to say usage is high, or that a leak has been found on your side of the boundary.
- The boiler keeps losing pressure and needs topping up every few days, with no drips at the radiators.
- You can hear water running in the walls or under the floor when nothing is on. (Our guide to hearing water running with the taps off covers the checks to do first.)
- A damp patch keeps spreading on a floor or wall, or a patch of lawn stays wet in dry weather.
- Pressure at the taps has dropped, or a pool is losing more water than evaporation explains.
Finding the leak before anything is dug up
The whole point of listening is to find the leak from the surface. Without a leak survey, the choices are to guess where the pipe has failed and start digging, or to replace the entire run. Both are slow, messy and expensive when the pipe runs under a block-paved drive, a kitchen floor or a mature garden.
With a survey, the engineer narrows the leak to a small area first. The aim is to open only that area and leave the rest of the drive, floor or lawn alone.
Acoustic detection alongside tracer gas and other methods
On a buried supply pipe under mains pressure, listening is often the first thing an engineer does after proving the leak, because it can cover a long run from the surface. On other jobs it is the second method: tracer gas may find the general area and listening pins it down, or the other way round. Several of the case studies on this site, such as the Dinmore and Bollington jobs, show exactly that, with two methods pointing at the same spot before anything was dug up.
When another leak detection method goes first
- Very slow leaks that make little sound are usually found with tracer gas.
- Leaks on heating pipes in a warm floor can show up clearly on a thermal camera with the heating running.
- Water coming in from outside, through a roof or wall, is traced with moisture mapping and thermal imaging.
- Non-pressurised pipes such as drains are checked with cameras and dye.
You do not need to know which method your leak needs. The office asks the right questions when you call and books the survey to suit what you describe.

