What Are the Signs of a Water Leak Under a Concrete Floor?

A hot water pipe under the slab can make a patch of floor feel warm to your bare feet. This warmth is often the first clue, especially in cooler months. You may also notice the floor feels uneven or slightly raised in one area.

Cracks in tile or grout, or a popping sound when you walk, can signal that water is pushing up from below. Laminate or hardwood flooring may start to cup or buckle. These changes happen slowly, so check your floors regularly for any new imperfections.

The sound of running water when all taps are off is a strong sign of a leak. You might hear a faint hiss or a continuous drip under the floor. This sound can be easier to notice at night when the house is quiet.

Your water meter can confirm a leak. Turn off all water inside and outside, then check the meter reading. Wait an hour and check again. If the reading changed, water is escaping somewhere, and a slab leak is a likely suspect.

Finding a leak under concrete requires specialized equipment. Pros use electronic listening devices and moisture meters to pinpoint the exact spot. This approach avoids unnecessary digging and reduces disruption to your floor and foundation.

Once the leak is located, the work usually involves accessing the pipe, repairing it, and drying the affected area. The process can take days, depending on the extent of the damage. The pros can also document the damage for your insurance claim. Policies vary, and your insurer decides what is covered.