Franklin houses where slab leaks happen
Franklin has a wider mix of houses than most towns in Johnson County. Homes around the courthouse square and in the Martin Place Historic District are mostly older houses over basements and crawl spaces. Ranch homes from the 1960s through the 1980s, and the newer neighborhoods on the north and east sides of town, are far more likely to sit on a concrete slab.
Older Franklin houses still turn up slab leaks in a less obvious place: additions. A kitchen extension, a family room or an enclosed porch was often poured as a slab and plumbed with lines that run under it to reach the original house. When those lines leak, the main house shows nothing and the addition’s floor is the only clue.
What a slab leak looks like before anyone finds it
A warm floor
A hot-side leak warms the concrete above it. Tile shows it best: a patch that feels warm under bare feet, often in a hallway, kitchen or bathroom.
A meter that won’t stop
With every fixture off, the small leak indicator on your meter keeps turning. Cold-side slab leaks are usually found this way.
Water you can hear
A faint hiss or rushing sound under the floor at night, when the house is quiet and nothing is running.
Damage at the edges
Damp carpet along a wall, baseboards swelling, or wood flooring that starts to cup near the leak.
A water bill that jumps from one month to the next, with nothing else changed, is often the first sign Franklin homeowners notice. See why is my water bill so high?.
Think you have a leak? Call and tell us what you’re noticing in your Franklin home.
(877) 729-0265Check your meter in five minutes
- Turn off all water useFaucets, toilets, washer, dishwasher, ice maker and any sprinklers. Wait for toilets to finish filling.
- Read the leak indicatorLift the meter pit lid near the curb or sidewalk. If the little triangle or dial is turning, water is moving.
- Close the main shutoff inside the houseIf the meter stops, the leak is inside the house or under the slab. If it keeps moving, the leak is in the buried line outside; see water line leak detection in Franklin.
- Isolate the water heaterClose the cold supply valve on top of the water heater. If the meter stops now, the leak is on the hot side.
How the leak is pinpointed
We work from the meter inward. Closing valves one at a time tells us whether the leak is on the hot side, the cold side or a branch to one fixture group. The suspect line is then pressurized and held on a gauge; a steady drop proves it’s leaking.
Next we trace the route of that line under the slab, because pipes rarely run where you’d expect. Listening along the route with an acoustic ground microphone finds the point where the sound of escaping water peaks, and a thermal camera shows the heat pattern from a hot-side leak on the floor surface. Where the two agree, we mark the floor.
Additions, porches and remodeled kitchens
| Where the leak shows | What we check first |
|---|---|
| Floor of a slab addition is warm or damp | The line that runs from the original house into the addition |
| Kitchen floor near an island sink | The island supply and drain lines that were run under the slab during a remodel |
| Enclosed porch or sunroom | Lines to an outside spigot that were enclosed when the porch was built |
| Bathroom added on a slab | Supply lines and shower valve on the new bath, and where new pipe joins old |
Where old and new pipe meet (galvanized to copper, or copper to PEX) is a common leak point in remodeled Franklin homes.
After the leak is marked
You get photos and notes with the line, the readings and the marked spot. Our plumbing partner can then repair it through one small opening, or reroute the line out of the slab; or you can give the report to your own plumber. See slab leak repair in Franklin for both options.
Slab Leak Detection: questions from Franklin homeowners
Do older Franklin homes get slab leaks?
The main house often doesn’t, because many older homes sit over basements or crawl spaces. Slab additions, enclosed porches and remodeled kitchens on those homes do, and so do ranch homes from the 1960s on and newer subdivisions.
How can I tell a slab leak from a leak in the yard?
Turn off all water, then close the main shutoff valve inside the house. If the meter stops, the leak is inside or under the slab. If it keeps going, the leak is in the buried line between the meter and the house.
Will you break my floor to find the leak?
No. Detection uses valve isolation, pressure testing, acoustic listening and thermal imaging. Only the repair needs an opening, and it’s made at the marked spot.
What if there’s more than one leak?
Pressure testing shows whether the line still loses pressure after the first leak is found. If it does, we keep searching, and the report lists each location.
Guides that go deeper
Sources: Indiana American Water; Town of Bargersville Water Utility; Indiana 811; Indiana Administrative Code, Title 327. Updated October 1, 2026.