Water bill climbing, a warm spot on the tile, or the meter spinning with everything off? Before anyone breaks concrete, the leak needs to be found. Call or send a few details, and a local slab leak plumber will get back to you about tracking it down.
Why finding it matters so much
Under a slab, guessing is expensive. Open the floor in the wrong spot and you’ve paid for a hole, a patch, and new tile, and the leak is still running. Good detection is what keeps a repair to one small opening, or tells you a reroute makes more sense than opening the floor at all.
How a plumber finds a slab leak
It usually starts at the water meter. With every faucet and appliance off, a moving meter means water is going somewhere it shouldn’t. From there the plumber narrows it down.
They’ll check whether it’s the hot side or the cold side, often by shutting off the water heater supply and watching the meter again. They’ll pressure test the lines to see which one won’t hold. Then they listen. Water forced out of a pinhole in a pressurized pipe makes noise, and acoustic equipment picks it up through the concrete. A thermal camera can show the warm trail of a hot water leak across the floor.
What you should end up with is a mark on the floor and an answer: which line, where it is, and what your options are for fixing it.
A leak isn’t always under the slab
Sometimes the meter’s moving and the culprit is a toilet flapper, an irrigation valve, or the line between the meter and the house. A good leak check rules those out first, so you don’t pay for slab work you don’t need. You can try a quick version yourself: how to check your water meter for a leak.
Drain leaks are different
Water and gas lines are under pressure. Drains aren’t, so a drain leak won’t move the meter and won’t make the same noise. Those get found with a camera and a hydrostatic test instead. See sewer and drain under the slab.
Ask these before you book
Ask what the detection includes, whether you’ll get the leak location marked and in writing, and whether the price of detection is credited if the same company does the repair. And if you’re filing an insurance claim, ask for a written report of what they found.
Meter moving and you don’t know why? Call or send the details.