Slab Leak Signs in Katy Homes: What to Look For

What a slab leak is

Many Houston-area homes are built on a concrete slab poured directly on the ground. In some homes, water supply lines or drain lines run in or under that slab. Supply lines in many homes run through the attic or walls instead, so not every house has this exposure. If a pipe in or under the slab cracks, corrodes or separates at a joint, water escapes into the soil or up through the slab.

A pressurized supply line leak is the kind most people mean by "slab leak." Drain line leaks under a slab are a different problem, though they can also cause damage and sometimes odors.

Common signs of a slab leak

No single sign proves a slab leak. Several together are a stronger reason to call a plumber.

An unexplained jump in your water bill

If your usage rises and you have not changed your habits, a hidden leak is one possible cause. Compare recent bills with the same months last year.

The water meter moves when everything is off

Turn off every faucet and appliance that uses water, including the ice maker and irrigation. Look at your meter. Many meters have a small leak indicator, often a dial or triangle, that spins when water is flowing. If it moves with everything off, water is going somewhere. A leak on the yard side of the meter or a running toilet can also cause this, so it is a clue, not proof.

The sound of running water

You may hear a hiss or trickle in the quiet of the night when nothing is on.

Warm or hot spots on the floor

A leak in a hot water line can warm the slab. You may notice a floor that is warmer than the rest, especially on tile, or notice the water heater running more often.

Damp or discolored flooring

Look for wet carpet with no clear cause, buckling or cupping wood or laminate, loose or cracked tiles, or damp spots that return after they dry.

Musty smells or mold

A persistent musty odor, or mold along baseboards and the lower part of walls, can mean moisture is coming from below. See our page on mold after water damage.

Low water pressure

A drop in pressure at some or all fixtures can be a sign, though it has many other causes.

Cracks in walls, floors or the slab

Moving soil can crack things, and leaks can add to it. Cracks alone do not mean a leak. They are worth having looked at.

Water at the foundation edge

Pooling or soggy soil along the slab edge when it has not rained can point to a line leaking outside.

Why slab leaks happen in the Houston area

The causes are general, and each home is different.

• Clay soil. Much of the Houston region sits on expansive clay. It swells when wet and shrinks when dry. That movement can stress a slab and the pipes in or under it over time.
• Dry spells and wet spells. Big swings in moisture, which the Gulf Coast often sees, increase soil movement.
• Pipe age and material. Older copper can corrode. Some homes built roughly from the late 1970s into the mid 1990s may have polybutylene supply pipe, which has a history of failures. Ask a plumber if you are unsure what you have.
• Water chemistry and pressure. High water pressure or aggressive water can wear pipes faster.
• Rubbing and settling. A pipe that rubs against concrete, rock or another pipe can wear through.
• Construction issues. Poor bedding or pipe damage during building can show up years later.

Newer homes often have post-tension slabs. Do not drill or cut into one. Tell any contractor if yours is one, because cutting a tendon is dangerous.

How plumbers find a slab leak

Finding it is a plumber's job. Texas plumbers are licensed by the Texas State Board of Plumbing Examiners. Check a plumber's license status before you hire.

Common methods include:

• Pressure testing. The plumber isolates the lines and checks whether pressure holds.
• Acoustic or electronic listening. Sensitive microphones pick up the sound of escaping water through the slab.
• Thermal imaging. A camera can show temperature differences, which helps with hot water lines.
• Line tracing and camera inspection, where a drain line is the suspect.
• Moisture meters to track dampness in flooring and walls.

A good plumber will tell you what they found, where, and show you the evidence.

Repair options, in general terms

The right fix depends on what is wrong, where, and how many lines are affected. A plumber should explain the options and give a written estimate. In general terms:

• Spot repair. The plumber opens the slab above the leak, repairs the pipe, and patches the slab. It can make sense for one clear failure.
• Rerouting. The plumber abandons the leaking line and runs new pipe through walls or the attic. It can make sense if the line has several problems or is hard to reach.
• Repiping. In some homes with failing pipe, replacing larger sections is discussed.
• Lining or other methods are sometimes offered. Ask about the pros, cons and what is covered.

We are not giving prices here. Costs vary widely with access, the number of leaks and the flooring above. Get written estimates and compare what each includes.

What restoration involves afterward

Fixing the pipe stops the water. It does not dry the house. If water has come up into the home, a restoration company typically:

1. Checks moisture in floors, walls, cabinets and subfloor
2. Removes wet flooring, baseboards or drywall that cannot dry in place
3. Sets drying equipment and monitors until readings return to normal
4. Cleans and treats affected areas
5. Documents the work for you and your insurer

Slab leaks often involve slow moisture, so mold may be a concern if the leak has gone on a while. See our page on slab leak water damage and our overview of water damage restoration in Katy. For cost context, read the restoration cost guide.

Insurance notes

Coverage for slab leaks varies. Many standard policies cover sudden and accidental water damage from plumbing, but some limit or exclude damage from long-term leaks, and some exclude the cost of reaching the pipe, such as tearing out the slab. Wording differs from policy to policy.

Check your policy, call your insurer and talk with your agent before you authorize major work if you can. Document everything, keep your plumber's report, and keep receipts. More in our guide on homeowners insurance and water damage in Texas. The Texas Department of Insurance has consumer help at tdi.texas.gov.

What to do first if you suspect a slab leak

1. Do the meter test described above.
2. Close the main water shutoff if you believe water is actively escaping and you cannot stop it. Know where the valve is.
3. Turn off the water heater's power or gas if you will have the water off for long, so it does not run dry. Check your manual or ask a plumber.
4. Stay out of wet areas near electricity. Do not touch outlets or cords near wet floors.
5. Take photos and video of any damage and the meter reading.
6. Call a licensed plumber to confirm and locate the leak.
7. Call your insurer to ask about your policy.
8. Call a restoration company if water has reached the living space. You can request help and we work to connect you with an independent local pro. The pro's own schedule sets the timing.

Sources

• Texas State Board of Plumbing Examiners, plumber licensing (tbpe.texas.gov and the state licensing search)
• Texas Department of Insurance: tdi.texas.gov
• U.S. Environmental Protection Agency, mold and moisture: epa.gov/mold

This is general information. Your home and policy are specific to you.