What is a Slab Leak?
A slab leak is a hot or cold water line leak which is located somewhere under the concrete building slab. Here in Albuquerque and Rio Rancho slab leaks are found on the west side of Albuquerque and in Rio Rancho where poly butylene piping was used to plumb the house. There are also occasional slab leaks found in the north east heights closer to the mountain. These houses are plumbed in copper and the pipe becomes corroded causing the pipe wall to thin out. This copper corrosion is often associated with a combination of elevated sulfate or chloride content in the soil in conjunction with poor drainage.
How do I know I have a slab leak?
The most obvious indication is water surfacing inside the house or around the edge of the concrete slab outside.
A leak under the concrete slab can run for weeks or even months without a single drop of water showing up above ground. Usually the home owner will find out they have a slab leak after they receive an unusually high water bill. The water company will also call and let you know they have detected high usage.
Other signs are:
- A hot area on the floor.
- A sudden drop in your hot water temperature.
- A drop in water pressure.
- Hot water heater running all the time.
- A sound of water running inside a wall but no visible signs of any water.
How do I know where the leak is?
A leak almost always needs to be professionally located. The lines are pumped up with a gas, holes are drilled in different areas around the house and special gas detection equipment sniffs for the gas underground. Gradually the source of the leak is narrowed down and a good location company can pinpoint a leak within a few square feet.
How is a slab leak fixed?
Once the leak has been located the flooring needs to be removed. Carpet can usually be pulled back but tile or laminate needs to be broken out. After that a hole is jack hammered through the concrete slab above the location of the leak. Once an adequate hole through the concrete has been made the plumber will dig down to the source of the leak. When leak is found and the pipe is exposed and the bad section is cut out of the line and replaced. The water is turned on the repair is pressure tested. If there is no sign of anymore leaking the sand is back filled and compacted and the concrete is replaced. The process can take 3-4 hours for an easy leak to over a day for more difficult repairs.
Copper line slab leaks are sometimes not repairable. The copper becomes so thin and corroded that cutting and soldering in a new piece is impossible. In this case the line is usually re-routed through the walls from one manifold to another. Another option in this case is a whole house repipe.