A slab leak happens when a water line under your concrete foundation begins leaking. These leaks can be hard to see at first because the water may stay under the floor, travel through the slab, or show up far away from the actual source.
If you suspect a slab leak, the goal is not to start breaking concrete immediately. The goal is to look for warning signs, shut off water if damage is active, and schedule professional slab leak detection so the source can be narrowed before repairs begin.
Common Signs of a Slab Leak
- Warm spots on the floor: This can happen when a hot water line leaks under the slab.
- High water bills: A sudden increase may mean water is running continuously.
- Water meter movement: If all fixtures are off and the meter is still moving, a hidden leak may be active.
- Damp flooring or baseboards: Moisture can travel up through floors, walls, and trim.
- Musty odors: Hidden moisture can create odors before water is visible.
- Sound of running water: You may hear water movement even when fixtures are off.
- Low water pressure: A leak in a pressurized line may reduce normal flow.
Step 1: Check Your Water Meter
Turn off faucets, showers, toilets, washing machines, irrigation, and any appliance using water. Then check your water meter. If the meter continues moving, you may have an active water leak somewhere in the system.
This does not prove the leak is under the slab, but it is an important clue that water is escaping from a pressurized line.
Step 2: Look for Floor and Wall Clues
Walk through the home and look for warm flooring, damp carpet, loose flooring, water near baseboards, bubbling paint, or staining on walls. A slab leak can travel before it becomes visible, so the wet area is not always directly above the leak.
Step 3: Listen for Water Movement
When the house is quiet and no fixtures are running, listen near bathrooms, kitchens, laundry rooms, water heaters, and flooring where you suspect a problem. A slab leak may create a faint hissing, rushing, or running-water sound.
Step 4: Avoid Guessing or Breaking Concrete Too Early
Breaking into flooring or concrete before detection can lead to unnecessary damage. Professional slab leak detection may use acoustic listening, pressure testing, thermal imaging, moisture readings, and line tracing to narrow the likely source.
Step 5: Schedule Professional Slab Leak Detection
If you have meter movement, warm floors, damp flooring, or unexplained moisture, professional slab leak detection can help locate the suspected leak area before repair work begins.
View our slab leak detection service or call (727) 666-5334 for help.
When It Becomes Urgent
If water is actively spreading, damaging flooring, or appearing near electrical areas, shut off the main water supply if safe and call for urgent help. If the source is unclear but water damage is active, emergency leak detection may be the right next step.