Slab Leaks in Las Vegas

Why This Valley Gets Them

Nearly every home in Clark County is built slab-on-grade — poured directly onto the ground, with no basement and no crawl space. Water supply lines run under or through that concrete. It is a sound construction method for this climate, but it has one consequence: when a supply line fails, it fails somewhere you cannot see or reach.

Add the valley's hard water and the picture completes itself. Decades of roughly 280 ppm water moving through copper pits it from the inside until a pinhole opens. Older neighbourhoods with original copper are where this shows up most — Spring Valley in particular has enough of it that locals treat it as a known local problem, and the Spring Valley page goes into why.

Hot lines fail first and most often. They run hotter, scale faster, and expand and contract more, so if you are going to get a slab leak it is usually on the hot side. That is exactly why a warm patch on the floor is the signature symptom.

The Warning Signs

• A warm area on the floor with no reason to be warm. The most recognisable sign there is.
• A water bill climbing without a change in habits. Slab leaks run continuously.
• Running water audible with everything off — usually noticed at night.
• Damp carpet, lifting tile or warping wood in one area, especially without a nearby fixture.
• Pressure dropping across the house.
• A musty smell from moisture in flooring or subfloor.
• Cracking in walls or flooring — late-stage, indicating the soil beneath has been affected.

The Meter Test You Can Run in Ten Minutes

Before calling anyone, this is worth doing yourself and it costs nothing:

• Turn off every tap, appliance, ice maker and irrigation zone in and around the house.
• Find the water meter, usually in a box near the street.
• Note the reading, or watch the low-flow indicator if the meter has one.
• Wait fifteen to thirty minutes without using any water.
• Read it again.

If the meter has moved, water is escaping somewhere. That is not proof it is under the slab — it could be irrigation, a toilet flapper or a hose bib — but it converts a suspicion into a fact, and it is genuinely useful information to have before anyone quotes you.

How They Get Located and Repaired

Finding the leak comes first, and modern location is largely non-invasive: acoustic listening equipment, pressure isolation to narrow down which line is involved, and thermal or electronic tracing. The point of paying for proper detection is to avoid opening concrete in the wrong place. The leak detection page covers the process.

Repair generally takes one of three forms:

• Spot repair. Open the slab at the leak, repair the pipe, close it up. Least disruptive overall when there is a single failure in otherwise sound pipe.
• Reroute. Abandon the under-slab section and run a new line overhead or through walls. Avoids breaking concrete and takes that run out of the slab permanently. Often the sensible answer when the pipe is old but only one section has failed.
• Repipe. Where a home has had several slab leaks, the pipe is telling you something. Replacing the supply system — typically in PEX — ends the cycle rather than treating it one pinhole at a time. See the repiping page.

Costs vary widely with access, location and method, so treat any figure quoted before an inspection with suspicion. What is not in doubt is the urgency: this is water running into the ground under your foundation, continuously, and it does not get better on its own.