Plumbing Advice
7 Signs of a Slab Leak in Your Arizona Home
By Kenneth Parks ·
Most Phoenix homes sit on a concrete slab, and in a lot of them, the water lines run under or through it. When one of those lines leaks, the water goes into the ground and the slab, not onto your floor, which is why slab leaks can run for months before anyone notices. Here's what to watch for.
1. Your Water Bill Jumped
The most common first sign. Nothing changed in the house, but the bill is up 30 or 50 percent or more. A slab leak runs 24 hours a day, so even a small one adds up.
2. The Meter Moves With Everything Off
Turn off every fixture and appliance, including the ice maker and irrigation, and watch the water meter. Most meters have a small leak indicator dial. If it's turning, water is leaving the system somewhere.
3. A Warm Spot on the Floor
If the hot line is leaking, the water warms the slab above it. A patch of tile or concrete that's noticeably warm underfoot, especially in a hallway or near a bathroom, is a classic hot-side slab leak. Pets often find it first.
4. Damp Flooring, Buckled Wood or Lifted Tile
Moisture wicking up through the slab shows up as a damp area on carpet, cupping in wood or laminate, or tile that sounds hollow and starts to lift.
5. You Can Hear Water Running
With the house quiet and everything off, a faint hissing or running sound near the floor or in a wall.
6. Low Water Pressure That Came On Gradually
A leak pulls pressure off the whole system. If the shower has slowly gotten weaker, and it's not a clogged head or a failed regulator, a leak is on the list.
7. Mold, Mildew or a Musty Smell With No Obvious Source
Moisture under a slab feeds mold at the base of walls and under flooring. If you smell it and can't find it, it may be below you.
Why Slab Leaks Happen Here
Phoenix homes from the 60s through the 90s often have copper lines under the slab. Copper reacts with the soil and the concrete, and with the minerals in our water. Ground movement and the original installation add stress. Eventually a pinhole opens up. Once one line has leaked, the others in the same slab are usually in similar shape.
What to Do Next
Don't start breaking floor. A slab leak is located with acoustic and pressure equipment to within a foot or two, so the repair is one small opening, or better, none. Once it's located there are three options: a spot repair at the leak, a reroute that abandons the leaking line and runs a new one overhead, or a whole-home repipe if the house has a history. We'll show you the location and give you real prices for each. Many homeowner policies cover the access and repair, so keep the documentation.
Slab leak detection and repair