Slab leaks: what they are, how we find them, and what repair costs

Water under your foundation can run for weeks before you see damage. Early detection saves thousands.

How slab leaks differ from cabinet leaks

Supply lines run through or under the concrete slab before they branch up to fixtures. When one of those lines pinholes, water spreads under the foundation — you may see none of it inside for a long time. Warm spots on the floor, unexplained moisture at the baseboard, or a spinning meter with everything off are slab-leak hallmarks. Cabinet leaks show up faster and cost less to reach.

Detection methods we use

Acoustic listening gear locates the hiss of escaping water through concrete. Pressure decay tests isolate which line is losing pressure. Thermal imaging picks up warm-water leaks under tile. We combine methods so we're not jackhammering on a guess. The goal is to confirm the leak, mark the location, and quote repair before anyone cuts concrete.

Reroute vs spot repair vs repipe under slab

Spot repair — open the slab at the leak and fix that section — works when the pipe is otherwise healthy and access is reasonable. Rerouting the line through walls or attic bypasses the slab entirely; often the better long-term fix on older copper under concrete. Full under-slab repipe is the last resort when multiple leaks or brittle pipe make patches pointless. We lay out all three with realistic timelines.

Insurance and documentation

Some homeowner policies cover leak detection and access; many exclude the pipe repair itself. Document the meter test, our detection report, and photos before and after. If you've had one slab leak, the same line may fail again — we tell you when rerouting beats filing a second claim in two years.