If you suspect you have a leak within your property but are unsure of its exact location, you should turn off your internal mains water stopcock and then check the dial on your meter. If your meter dial is still moving, then you may have a leak within your boundary. If you turn back on your internal stopcock and the meter starts to move this suggests that the leaks is within your property. If the meter does not move it suggests that the leak is not related to any of your pipework and maybe an external source or waste pipe.