How to Find Exactly Where a Copper Pipe Is Leaking Under a Slab

Read your water meter and compare the usage from one month to the next. If you notice a significant jump in usage that can't be explained in others ways, you may have a leak somewhere in your system.

Observe the floor covering on top of your slab. A leak can often result in a wet spot on carpeting or rugs right over the area of the leak.

Walk across the slab floor barefoot if there is no carpeting or flooring on the slab. A leak in a copper hot water pipe can sometimes result in a hot spot above the leak.

Listen for the sounds of running water when none should be running. You may be able to hear a large leak with an unaided ear, but smaller leaks cannot be heard without the assistance of professional equipment.

Contact a professional. In most cases, a copper pipe leak cannot be located with any degree of certainty without the use of professional equipment. A professional plumbing contractor will bring in pipeline location equipment to determine exactly where your pipes are located under the slab. She will then use an amplified microphone system to listen for a leak under the slab.