Slab Leak Detection & Under-Foundation Repair
A slab leak is a leak in a water or sewer line buried beneath a home's concrete foundation slab. Detection pinpoints the leak through the slab using acoustic listening, infrared imaging, and pressure testing, so repair opens one targeted spot instead of breaking up large sections of floor.
5 Urgent Warning Signs
- ⚠️ A warm or damp spot on the floor, or flooring that buckles or darkens in one area
- ⚠️ The sound of running water when no fixture is on
- ⚠️ A water meter that keeps spinning with all taps closed (the classic meter test)
- ⚠️ A water bill that jumps without a change in use
- ⚠️ Cracks in walls or floors, doors that start sticking, or musty smell near the slab — especially on expansive clay soil
4-Step Technical Protocol
Step 1: System isolation
shut off fixtures zone by zone and run the meter test to confirm a supply-side leak and which line it is on.
Step 2: Acoustic / thermal location
electro-acoustic listening discs and FLIR infrared cameras narrow the leak to a small area through the slab.
Step 3: Targeted access
open only the pinpointed section of floor; confirm the failed fitting or pipe section visually before repair.
Step 4: Flow verification
pressure-test the repaired line, re-check the meter with all fixtures off, and restore the floor.
Frequently Asked Questions
How do I know it is a slab leak and not a normal plumbing leak?
Do the meter test: turn off every tap and appliance, then watch the meter. If it still moves, water is escaping somewhere in the system. Warm floor spots, running-water sounds with everything off, and unexplained bill jumps point specifically under the slab.
Does the whole floor have to come up?
No — that is the point of acoustic and thermal detection. A located leak is usually repaired through one small opening. Full-slab work is only for lines that have failed in multiple places, in which case rerouting above the slab is often discussed instead.
Why do slab leaks happen more in some cities?
Expansive clay soil (Jackson's Yazoo clay, Little Rock's high-plasticity clay) swells when wet and shrinks when dry, flexing rigid copper lines until pinholes form and pulling joints apart. Homes on that soil are the highest-risk group.
🛠️ Standard Trade Equipment
Electro-acoustic listening discs / ground microphones, FLIR infrared cameras, line-isolation pressure gauges, electronic line locators, concrete cutting tools for targeted access.
📍 Available Service Hubs
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