What is a slab leak?
Most houses in Delray Beach are built slab-on-grade: the floor is a concrete slab poured directly over compacted sand, with water supply lines and drain lines laid in the sand before the pour. When one of those pipes fails, water escapes into the fill beneath the house instead of dripping somewhere you can see. That hidden location is what separates a slab leak from an ordinary plumbing leak, and it is why the leak has to be located with instruments before anyone breaks concrete.
Slab leaks fall into two groups. Pressure-side leaks happen on the copper, galvanized, CPVC or PEX lines that carry hot and cold water, and they run every hour of the day because the line is always under city pressure. Drain-side leaks happen on the cast iron or PVC drain lines under the floor; they only leak when water goes down a drain, so they do not move the water meter and are confirmed with a hydrostatic plumbing test instead of a pressure test.
Signs of a slab leak in your home
- A water bill that climbs while your household usage stays the same, or a water meter that keeps moving with every fixture turned off.
- A warm or hot spot on a tile or wood floor, which usually points to a leak on the hot water line.
- The sound of running water inside a wall or under the floor when nothing in the house is on.
- Damp carpet, cupping or lifting wood flooring, loose tiles, or white mineral deposits along grout lines and baseboards.
- A water heater that runs far more often than it should.
- New cracks in the slab or walls, or doors that begin to stick, after water has washed sand out from under part of the floor.
- A musty odor, or water collecting along the outside of the foundation when there has been no rain.
If your meter shows a leak but nothing inside the house is wet, the leak may be on the main water line between the meter and the house rather than under the slab. Our water leak detection service separates the two before any repair is proposed.
Why slab leaks are common in Delray Beach
Several local conditions work against pipes buried under a slab here:
- Housing age. Much of Delray Beach was built between the 1950s and the 1980s, when soft copper runs under the slab were standard practice. After forty to seventy years, those lines develop pinholes from the inside out.
- Sandy fill and a high water table. The sand beneath the slab shifts slightly as groundwater rises and falls through the rainy season, and a pipe resting against concrete, rebar or rock wears thin at that contact point.
- Hot water expansion. Copper expands and contracts every time hot water runs through it. Where the pipe is locked in concrete, that movement abrades the pipe wall, which is why hot-side slab leaks outnumber cold-side leaks.
- Coastal groundwater. Homes near the Intracoastal Waterway and the ocean sit in groundwater that is more corrosive to buried copper and cast iron.
- Water pressure. Pressure that runs high, or a pressure-reducing valve that has failed, puts constant extra load on pipes that are already thin.
- Cast iron drains. Under-slab cast iron drains in older homes corrode along the bottom of the pipe and crack, letting wastewater move through the sand under the floor.
How we find a slab leak
Meter and pressure check
We confirm that water is being lost and read the static pressure of your plumbing system.
Line isolation
We separate the hot side from the cold side, and the house from the main line, to identify the exact pipe that is leaking.
Line tracing
An electronic locator follows the pipe's route through the slab, because pipes rarely run where plans show them.
Acoustic listening
Ground microphones pick up the sound of pressurized water escaping through the pipe wall and narrow the search to a small area.
Thermal imaging and moisture mapping
A thermal camera shows the heat pattern of a hot water leak, and moisture readings show how far water has travelled.
Marking and options
We mark the leak point on the floor and explain every repair option before any concrete is opened.
Slab leak repair options
The location of the leak, the condition of the rest of the pipe and the floors above it decide which repair makes sense. We explain every option that fits your house and you choose.
| Repair method | How it works | Best suited to |
|---|---|---|
| Direct spot repair | We open the slab at the marked leak point, replace the damaged section of pipe, pressure test the line and patch the concrete to floor level. | A single leak under an accessible area, on pipe that is otherwise in fair condition. |
| Tunneling | We dig beneath the foundation from outside the house to reach the leak, so interior floors are not broken. | Leaks near exterior walls, or under stone floors, cabinets and tubs that are costly to disturb. |
| Reroute (bypass) | We abandon the failed line under the slab and run a new PEX or copper line through the attic and walls to the same fixtures. | Hot water lines with a history of leaks, or leaks under areas that should not be opened. |
| Whole-house repipe | We replace every supply line in the home and retire all of the original under-slab piping. | Homes with repeated slab leaks, or aging copper, galvanized or polybutylene pipe throughout. See repipe services. |
For a single pinhole on otherwise healthy pipe, a spot repair is the sensible choice. For a second or third leak on the same copper system, a reroute or a repipe avoids opening the floor again the next time the old pipe fails.
What happens after the repair
Every repaired line is pressure tested before the concrete is patched or the tunnel is backfilled. Where the slab was opened, we compact the fill, patch the concrete to floor level and leave the surface ready for your flooring installer.
If water has spread under flooring or into walls, drying should start the same day to prevent mold, and we show you which areas are wet so a water mitigation company can place equipment where it is needed. If sand under the slab has washed out, we tell you so a structural engineer can check the foundation. Our foundation leak repair page explains that situation in detail.
Does homeowners insurance cover a slab leak?
Many Florida homeowners policies pay to access the leak, meaning breaking and restoring the slab (often listed as "tear out and access"), and to repair sudden water damage, while excluding the failed pipe itself. Coverage differs between policies and carriers, so check your declarations page or ask your agent. We record the leak location, the detection results and photographs of the damaged pipe so your adjuster has the evidence the claim needs. Read more about how we document every job.
Plumbing services in Delray Beach
Slab leaks are one part of the work we do. Every service below is available across Delray Beach, and the complete list is on our plumbing services page. When you are ready, our contact page covers what to have on hand when you call.
- Water Leak Detection
Pinpoints hidden leaks under slabs, in walls and underground before anything is opened.
- Foundation Leak Repair
Stops leaks that are washing out the sand beneath your slab and threatening the foundation.
- Pipe Leak Repair
Repairs pinhole, fitting and cracked-pipe leaks inside walls, ceilings and cabinets.
- Sewer Line Repair
Camera inspection and repair of the drain and sewer line from your house to the city main.
- Water Line Repair
Repairs or replaces the underground service line between the water meter and your home.
- Repipe Services
Replaces aging supply pipe with PEX or copper routed through the attic, off the slab.
- Burst Pipe Repair
Stops the water, replaces the ruptured section and checks the system for the cause.
- Hydrostatic Plumbing Testing
Tests the drain lines under your slab for leaks with water, plugs and a camera.
- Emergency Plumbing Services
Around-the-clock response to active leaks, sewer backups and main line breaks.
Delray Beach neighborhoods we serve
Slab leak questions
Can a slab leak be repaired without breaking up the floor?
Often, yes. Tunneling reaches the leak from outside the foundation, and a reroute replaces the failed line through the attic and walls, so interior floors stay intact. A direct spot repair through the slab is the most efficient choice when the leak sits under an open, accessible area such as a hallway or closet.
How long does slab leak repair take?
Locating the leak usually takes a few hours. A direct spot repair is normally completed in one working day, followed by concrete patching. Tunneling and reroutes typically take one to three days, depending on the depth of the pipe and the layout of the house.
Is a slab leak an emergency?
A leak on a pressurized water line runs 24 hours a day, so it keeps adding water under your slab until it is stopped. If you see water surfacing, hear water running under the floor or feel a warm spot that is spreading, close the main shutoff valve and call. Our emergency plumbing services cover slab leaks at any hour.
Can a slab leak damage my foundation?
Yes, over time. Water moving under a slab carries away the sand that supports the concrete, leaving voids that lead to settlement and cracking. Finding the leak early keeps a pipe repair from becoming a structural repair. See foundation leak repair for what happens when a leak has already affected the soil.
Why is one spot on my floor warm?
A warm spot on a tile or wood floor usually means a hot water line is leaking beneath it. Close the cold water supply valve on top of your water heater to slow the leak, and call us to confirm the location with thermal imaging and acoustic listening.
Should I repipe after one slab leak?
Not automatically. A single leak on pipe that is otherwise in good condition is usually handled with a spot repair or a reroute of that one line. If the pipe shows widespread thinning or you have had more than one leak on the same system, a whole-house repipe is worth considering.