Plumbers find hidden leaks with non-invasive tools: acoustic listening equipment, infrared cameras, pressure testing of isolated pipe sections, and moisture meters.

Finding Leaks Without Tearing Up Your Home

Hidden leaks happen behind walls, under floors, in ceilings, and beneath slab foundations. Instead of cutting into surfaces blindly, a leak detection specialist narrows the search to a specific spot first, so one small access hole replaces a demolished bathroom.

Step One: Confirming There Is a Leak

The first job is proving water is escaping and which system it is coming from. Plumbers close every fixture and watch the water meter. If the leak indicator keeps moving, water is leaving the pipes somewhere. Closing the valve on the water heater separates a hot-side leak from a cold-side leak, and isolating the irrigation system rules it in or out. A pressure test on a closed section shows whether it holds and which branch is losing water. Drain and sewer lines are not pressurized, so those are checked with a camera, dye, or a separate test.

The Tools That Pinpoint the Location

  • Acoustic listening equipment: Sensitive ground microphones pick up the hiss of pressurized water escaping a pipe, even through a concrete slab, and can locate the leak within inches.
  • Infrared thermal imaging: A leaking hot water line warms the slab or wall above it, and a cold line leak shows as a cooler, evaporating patch. The camera makes those temperature differences visible.
  • Pressure testing: Isolating hot, cold, and individual branches to confirm which line is failing.
  • Moisture meters: Confirm which drywall, flooring, or subfloor is actually wet, and how far the water has spread.
  • Video camera inspection: A camera on a flexible line travels through drains and sewer pipes to find cracks, separations, and root intrusion.
  • Tracer gas: In tough cases, a harmless gas is pushed into the drained line and a sensor finds where it escapes.

Signs You Might Have a Hidden Leak

  • A water bill that climbs with no change in habits
  • The sound of running water when nothing is on
  • Warm spots on a tile or concrete floor
  • Damp carpet, buckling wood floors, or cracked tile
  • Musty smells, mold, or peeling paint on walls and ceilings
  • A sudden drop in water pressure
  • An unusually green patch of lawn or soggy soil near the foundation
  • New cracks in the foundation or doors that no longer close cleanly

Why Slab Leaks Are So Common in Central Texas

Most Austin and San Antonio homes sit on slabs with water lines running beneath the concrete. Expansive clay soils swell when it rains and shrink in drought, moving the slab and stressing those pipes. Add hard water from the Edwards Aquifer and Highland Lakes, which contributes to pinhole corrosion in copper, and the constant expansion of hot water lines, and slab leaks can run for months before any sign reaches the surface.

What You Can Check Yourself vs. When to Call

You can do the meter test, put food coloring in each toilet tank to catch a leaking flapper, look under every sink, check the water heater drain pan, and walk the yard after the irrigation runs. If the meter moves with everything off, you feel a warm spot on the floor, or moisture appears with no visible source, stop there. Anything under the slab or inside a wall needs professional equipment, and cutting blindly causes more damage than the leak. If water is actively flowing, shut off the main and call.

Leak Detection From Radiant

Radiant has located and repaired hidden leaks for Austin and San Antonio homeowners since 1999. Our licensed technicians use modern leak detection equipment to find the source with minimal disruption, and we are available 24/7. You approve upfront pricing before any work starts, there are no surprise fees, and our Home Comfort Guarantee backs the repair. Call or schedule online before a small leak becomes a big one.