Quick answer
A slab leak is a leak in a water or drain pipe under your home's concrete floor. Common signs are a warm or damp spot on the floor, the sound of running water when every tap is off, a water meter that keeps moving, cracked tile, and a water bill that jumps without a reason. If you see these, do the meter test below, shut off the main valve if water is coming up, and book a plumbing Hero.
Why it matters in older St. Petersburg homes
About half of St. Petersburg's homes were built in 1969 or earlier, based on Census housing data. Many homes on concrete slabs from that era have copper or older pipes running under or through the slab. After decades, pipes can wear thin from water chemistry, movement in the ground, or rubbing against concrete. Cast-iron drain lines under older slabs can also crack or rust through.
The signs to watch for
- A warm spot on tile or flooring, often from a hot water line leak.
- Damp carpet, swollen baseboards, or a musty smell with no visible source.
- The sound of running water when nothing is on.
- A water heater that runs more than usual.
- New cracks in floor tile or walls.
- Low water pressure at several fixtures.
- A water bill that rises with no change in use.
- For drain leaks: slow drains, sewer odor, or damp spots near bathrooms.
The meter test
Turn off every faucet, appliance, and irrigation zone. Find your water meter, usually in a box near the street. Write down the reading or note the position of the leak indicator, wait without using any water, and check again. If it moved, water is leaving the system somewhere.
Next, close the main shutoff at the house. If the meter still moves, the leak may be between the meter and the house. If it stops, the leak is likely inside, possibly under the slab.
What to do first
- If water is surfacing through the floor, close the main water shutoff.
- If a hot water line may be leaking, turn off the water heater supply too.
- Move rugs and furniture away from wet areas and take dated photos.
- Call your insurance agent if there is visible damage, and ask what they need.
- Book a plumbing Hero to locate the leak before anyone opens the floor.
How a Hero finds a slab leak
A plumbing Hero confirms the leak with pressure testing, then locates it with listening equipment, thermal imaging for hot lines, or a camera for drain lines. Finding the exact spot first limits how much floor needs to be opened.
Repair options
The Hero will explain the choices for your home: opening the slab to repair the pipe at the leak, rerouting the line through walls or the attic, or replacing a larger section of old piping if more leaks are likely. In homes with galvanized or very old copper, a rerouted or replaced line can make more sense than a single spot repair. Ask your Hero whether the job needs a permit and which building department handles it.
What raises the risk
Risk tends to be higher when a home still has its original piping, when water pressure runs high, when hot water lines travel a long way under the floor, and after the ground shifts during long, heavy rain. A home that has had one slab leak can have more on the same pipe run, which is why a Hero may talk about rerouting instead of a single patch.
Questions to ask your Hero
- Where exactly is the leak, and how was it confirmed?
- Is it a supply line or a drain line, hot or cold?
- What are the repair options, and what does each one mean for floors, walls, and cabinets?
- Is the rest of the pipe in similar condition?
- Does the job need a permit?
- What does the Hero workmanship warranty cover on this repair?
How HALOFIX handles a plumbing booking
You book once. HALOFIX assigns one credential-reviewed plumbing Hero, and you can see the Hero's profile before arrival. The Hero inspects first, gives an estimate range, and sets the final price after inspection. If the scope changes, the Hero needs your written approval before going further. The booking hold is shown before you confirm, and you can choose the emergency option when water is actively coming in. Dispatch depends on Hero coverage and availability.
FAQ
- How do I know if I have a slab leak? Look for a warm or damp floor, running-water sounds with taps off, a moving water meter, and an unexplained bill increase. The meter test is a simple first check.
- Is a slab leak an emergency? If water is coming through the floor or near electrical outlets, shut off the main valve and choose the emergency option when you book. A slow leak still needs prompt repair to limit damage.
- Do I need to break up the floor to fix a slab leak? Not always. A Hero first locates the leak, then explains whether a spot repair, a reroute, or a section replacement fits your home.
Book a plumbing Hero
Suspect a leak under the floor? See plumbing in St. Petersburg or start your booking.