Leaking pipes under the foundation are commonly caused by corrosion, especially in the iron water lines used prior to the 1970s. There was also a period when certain types of copper lines prone to pinholes were used. But any type of pipe can become leaky due to any sort of ground movement, excessive water pressure, or water hammer (“banging pipes” due to sudden pressure changes).
So how do you know if you have a slab leak? Here are some important clues.
If you hear sounds of running water with nothing turned on, that’s an emergency!
But there may also be no symptom other than a jump in usage on your monthly water bill. But there’s still progressive harm, and all leaks can suddenly worsen.