Slab Leak Repair
A leak under concrete gives you almost nothing to work with: a warm patch, a sound, a bill. Locating it precisely is what decides whether the repair is one square foot of floor or a room.
Common in Georgia subdivisions built on slab from the 1990s onward.
Under the concrete
What a slab leak is, and how it shows itself
In a slab-on-grade house the ground floor is a poured concrete pad, and the water supply lines either run within that pad or beneath it in the fill. When one of those lines fails, the water has nowhere visible to go. It saturates the ground under your house, works its way along the underside of the slab, and only eventually produces a symptom you can see.
The things that give it away:
- A warm spot on the floor. The single most recognisable sign, and it means a hot water line. You can often feel it barefoot before you can measure it.
- Running water with everything turned off, sometimes heard as a faint hiss through the floor at night.
- A water bill that stepped up without a change in household use.
- Damp carpet, lifting vinyl or tile, or a hairline floor crack that stays wet.
- Low water pressure throughout the house as supply escapes before it reaches the fixtures.
- The water heater running constantly because it is reheating water that never reaches a tap.
- A musty smell, or mould appearing at the base of a wall where moisture is wicking up through the slab.
Georgia specifics
Why slab leaks happen in Georgia houses
Slab construction became common in Georgia subdivisions from roughly the 1990s onward, and much of that housing stock is now old enough for its first failures. Several local factors stack up:
Clay movement. Georgia red clay swells when wet and shrinks when dry, and it does that seasonally. A slab sitting on it moves, and pipes cast into or under a moving slab are worked at their joints year after year until something gives. This is the background cause behind a large share of slab leaks in the state.
Abrasion. A copper line moving even fractionally against concrete or gravel wears through from the outside. Lines that were laid without a proper sleeve through the slab penetration are the usual candidates.
Water chemistry and pressure. Aggressive water pits copper from the inside, producing pinholes. High municipal pressure, anything much above 80 psi, accelerates every one of these mechanisms, and a failed pressure regulator is a genuinely common contributing cause.
Age and material. Copper under a slab has a long but finite life. Polybutylene under a slab, in houses of the late seventies to mid-nineties, has a shorter one and tends to fail repeatedly.
Before any concrete moves
Nobody should break concrete to go looking
The rule with slab work is that locating comes first and it comes properly. Breaking concrete speculatively is expensive, disruptive and it may not find the leak. A competent slab leak visit follows a sequence:
Confirm the leak exists
Meter test with the house isolated, then isolate hot from cold at the water heater and pressure test each side separately. That establishes there is a leak and which system it is on, half the search eliminated before any equipment comes out of the van.
Narrow the run
The plumber works out where the lines are likely to run based on the fixture layout and the age and style of the house, then uses thermal imaging to read the slab surface. A hot water leak often shows as a clear plume on the floor.
Pinpoint acoustically
Ground microphones pick up the sound of pressurised water escaping and trace it to a point. This is done in quiet conditions, which usually means early morning with the household still. In difficult cases the line is charged with inert gas so the escape point can be heard or detected precisely.
Mark, then decide
The location is marked on the floor with a stated confidence, and only then do you choose a repair route. You should be told how certain the technician is before anyone brings in a saw.
Insist on location before demolition. Any plumber worth using will insist on it too.
Book Slab Leak DetectionThree routes
Break through, reroute, or repipe
Break-through repair
Cut a neat opening in the slab at the marked point, excavate to the pipe, replace the failed section, then backfill and patch the concrete. It keeps the original pipe routing and is often the cheapest option when the location is confident, the pipe is otherwise sound and the spot is not under a kitchen island or a tiled bathroom. The disruption is real: dust, noise, and floor covering that has to be lifted and reinstated.
Reroute overhead
Abandon the failed under-slab section and run a new line through the walls and attic instead. No concrete is broken, the work is often faster, and crucially the new pipe is accessible for the rest of the building life. The trade-off is drywall repair where the line drops down to fixtures, and in an unconditioned attic that new run has to be insulated properly against the freeze nights.
Repipe the house
If you are on your second or third slab leak, or the pipework is polybutylene, repairing individual failures is the most expensive way to arrive at the same destination. A full repipe takes the supply system out from under the slab entirely and puts it somewhere reachable. See whole-home repiping.
Ask for all three priced, not just the one the plumber prefers. It is your floor.
Get Options and PricingThe variables
What actually moves the price
Slab leak repair prices vary more than almost any other plumbing job, and the reason is that the plumbing is often the small part. What drives the number:
- Where it is. Under an open hallway is a different job from under a kitchen island, a built-in wardrobe or a tiled shower base.
- Floor covering. Carpet lifts and relays. Sheet vinyl usually does not survive. Tile has to be cut and matched, and matching a tile discontinued in 2004 is its own problem.
- Depth and slab construction. Post-tension slabs, rare in Georgia residential but not unknown, require particular care and specialist scanning before any cutting.
- Pipe material and condition. A single copper pinhole is one job. Polybutylene is a different conversation entirely.
- How long it has been leaking. Saturated fill, damaged flooring and mould all add scope that has nothing to do with the pipe.
- Reroute complexity. Single-storey with an accessible attic is straightforward. Two-storey with a fixture in an interior wall is not.
Whatever the route, you get the price before work starts, and you approve it before any concrete is cut or any wall opened.
The cost of delay
Why this is not a leak to live with
A slab leak is rarely a midnight emergency, and that is exactly why people leave them. The problem is that unlike a dripping tap, a slab leak gets structurally worse rather than just wasteful.
Water under a slab saturates and softens the fill the concrete is bearing on, and in expansive Georgia clay it also changes how that clay behaves, wetting a soil that swells is not a neutral act. Over months that can mean settlement, floor cracks and doors that stop closing. Meanwhile a hot water leak is heating the ground around the clock, so your water heater runs continuously and the bill compounds. Moisture wicks up into wall plates and skirting, and in Georgia humidity mould follows.
The realistic timeline is weeks, not months. Get it located, understand the options, and decide with real numbers in front of you.
Suspect a slab leak? Locating it is a single visit and it ends the guessing.
Call (866) 559-0826Questions we get on the phone
Answered plainly
Run the meter test with every fixture off, if the meter moves, water is escaping. Then check whether the floor has a warm patch, which indicates a hot line. Rule out toilets, irrigation and the water heater relief valve first, since all three are more common and cheaper to fix. A plumber confirms it by isolating hot and cold and pressure testing each side.
Often, but not always. Rerouting avoids concrete work and leaves the new pipe accessible forever, which is a genuine long-term advantage. Breaking through can be cheaper and less disruptive when the location is confident, the spot is in an open area, and the rest of the pipework is sound. Get both priced and choose with the numbers in front of you.
Many Georgia policies cover the resulting water damage and the cost of accessing the leak, while excluding the failed pipe itself, and policies vary widely on gradual damage. We cannot tell you what yours covers. Document everything from the first day, keep the detection report, and notify your insurer before work begins rather than after.
It can contribute to movement. Continuous water saturates the fill supporting the slab and changes the behaviour of expansive clay beneath it, and over an extended period that can show up as settlement, floor cracks or doors and windows that stick. Most leaks caught within weeks do not get that far, which is the argument for not sitting on it.
It is a pattern, and patterns mean a systemic cause: polybutylene pipe, aggressive water chemistry attacking copper, water pressure above about 80 psi, or a slab that is moving. At that point paying for individual repairs is usually the expensive path, and a repipe deserves a serious look. Have the static pressure checked as well. It is cheap and it is often part of the answer.
Usually not. A break-through repair is a noisy, dusty day or two in one room and the water is off for part of it. A reroute is generally less disruptive but touches more of the house. If flooring and drywall reinstatement follow, that is a separate contractor and a separate schedule, and that is the part more likely to affect living arrangements.
Warm patch on the floor?
That is usually a hot water line under the slab, and it is heating your foundation around the clock.
(866) 559-0826