Slab leaks on North Texas clay

Much of the Metroplex sits on Blackland Prairie and similar clay soils that swell when wet and shrink in drought. Most newer DFW homes are built slab-on-grade with water and drain lines under the concrete. Soil movement can crack slabs and stress those pipes, and a pipe leaking under a slab can also soak the soil and make movement worse.

Warning signs

• A water bill that jumps without explanation
• Warm spots on the floor (a hot-water line leak)
• The sound of running water with everything off
• Damp carpet, cracked tile, or swelling wood flooring
• New cracks in drywall, sticking doors, or gaps at window frames
• The water meter's leak indicator moving with all fixtures off

What to do

1. Turn off all fixtures and watch the meter's leak indicator.
2. If it moves, close the main and call a licensed plumber with leak-detection equipment. Check the license at tsbpe.texas.gov.
3. Photograph damp areas and call your insurer about their process.
4. If flooring, walls, or cabinets are wet, a restoration contractor can measure moisture and dry the structure.
5. If you see foundation signs, ask a structural engineer or foundation specialist for an independent opinion before agreeing to repairs.

Repair options

Plumbers may tunnel under the slab, cut through the floor, reroute lines through walls or the attic, or repipe. Ask each plumber to explain the options in writing. Policies often treat the resulting water damage differently from the cost of fixing the pipe or the foundation, so ask your insurer.

How our referral works

We are a referral service, not a contractor. When you send a request, we connect you with an independent restoration contractor who serves your city. You contract with and pay that contractor directly, and you are always welcome to choose someone else.

How to check a contractor in Texas

• Texas does not issue a statewide license for general water damage restoration, so ask about training and track record. Many firms train crews to IICRC standards; ask which certifications their technicians hold.
• Plumbing work requires a license from the Texas State Board of Plumbing Examiners. Look the plumber up before work starts.
• Mold assessment and remediation above a small-area threshold require licenses from the Texas Department of Licensing and Regulation, and the assessor and remediator on a job generally must be different companies.
• Some cities require registration or permits for certain repairs. Ask whether permits are needed.
• Ask for proof of liability insurance, a written estimate, and a written contract. Read any assignment-of-benefits or direction-to-pay form before you sign.

Related: water damage · slab leaks · frozen pipes · hail and roof leaks · flash floods · mold · guides

Guides: What Winter Storm Uri Taught DFW Homeowners · Hard Freeze Prep Checklist for DFW Homes · Documenting Hail and Storm Damage in North Texas · Clay Soil, Foundations, and Hidden Leaks

Common questions

Can drought cause slab leaks?

Clay soil shrinks in drought and swells after rain. That movement can stress foundations and the pipes in them.

Is a slab leak an emergency?

A hot-water leak or visible water should be handled quickly. Close the main if you cannot isolate it.