slab leak crack in ground sign

Slab Leaks: A Costly Problem

Don’t let a slab leak get the best of you! Early detection is key to preventing further damage.

A slab leak, also known as a foundation leak or concrete slab leak, is a plumbing industry term for a leak within the waterline piping below the concrete floor of your home or business. Slab leaks are an issue in homes and buildings of all ages, and can quickly become a very costly problem. Not only does a slab leak waste an excessive amount of water, but a leaking pipeline system can quickly cause damage to the foundation of your home or business, not to mention compromise your entire structure.

Read the full post here…

Slab Leak Symptoms

  • The sound of running water, even though all water is turned off
  • A hot spot on the floor
  • Cracks in walls or floors
  • Mildew or excessive moisture underneath carpets
  • Water on the floor
  • Wet baseboards
  • Wet planters near the building
  • Water coming out below the water heater, but the platform is dry
  • Sudden, unusually high water bill

Slab Leak Causes

There are a number of factors that can cause a slab leak. Here are the big ones:

  • Electrolysis. Electrolysis is a chemical reaction between copper piping, soil composition, and electrical current that causes the copper to corrode and start leaking.
  • Improper Wrapping of exposed piping is another common cause of water pipe erosion. Water running through the system causes the pipes to move slightly, especially hot water lines. The expansion and contraction combined with an improperly exposed pipe can damage the pipe causing it to leak.
  • Kinked or Nicked Line refers to a water pipe that was damaged during the original install, or by a workman from a different trade such as concrete slab laying. This weak spot in the line, combined with temperature changes, corrosion and other various factors can wear through, eventually causing the pipe to fail, resulting in a leak.
  • Ground Shifting is another common cause. After a foundation has been laid, a structure is built on top and then furnished and used. This causes the ground below to settle under all that weight over time, causing shifting that will eventually break water lines. Earthquakes large and small can also cause the ground to move.

Slab Leak Detection

When your business isn’t getting enough hot water, it might not be a problem with your water heater. You could have a slab leak.

Reliable Water Services’ Asset Control Specialist Chad Spurrier explains, “When you have water escaping in a slab leak situation, your hot water is constantly flowing and constantly causing your water heater to fire. That constant firing reduces the life of your water heater. If the hole in your piping is large enough, your water heater can’t keep up. The water heater will stay fired and never shut off, but you still won’t get enough hot water flowing through your faucets.”

The bottom line here is that slab leaks are no joke. If you suspect a slab leak, always hire a qualified plumbing technician to accurately and completely diagnose the problem.

A company specializing in slab leak detection will use one of several non-destructive detection techniques, such as:

  • Acoustic Survey
    • Electronic amplification equipment designed to “hear” leaking sounds and determine exactly where the leak is. A microphone designed to hear through the floor can pinpoint the exact location of the leak.
  • Line Tracing Equipment
    • Electromagnetic pipeline locators enable technicians to visualize the copper piping plumbing layout, and determine where the leak is located within the system
  • Isolation
    • Both ends of the leaking pipeline are exposed and the leak is stopped by the technician. It is then replaced after the leak has been properly identified, capped and no longer leaking.
  • Hydrostatic Pressure Testing
    • By filling the pipe system with a dyed water, leaks can be detected by adding pressure to the system. If there is a pressure loss, then there’s definitely a leak in the system, and the colored water will help to determine exactly where the leak is located.

By using proper modern tools of detection and identification, a skilled technician can find and diagnose your exact problem. If they’re doing things right, they’ll save time and money, while minimizing property damage. Sometimes, only a single tile may need to be removed and replaced.

Unfortunately, slab leaks are contagious: where there’s one crack or leak, there’s usually more. Moreover, repairing one slab leak can result in increased pressure on the pipes down the line (especially weak points like elbows), causing more slab leaks both immediately and over time.

Slab Leak Solutions

Also unfortunately, slab leak detection and repair can be costly. However, the safety and functionality of your structure depends on accurate detection and efficient repair.

  • Spot Repair
    • Opening up the slab at the area of the leak to repair the leaking pipe.
  • Re-Pipe or Reroute
    • Replacing the entire leaking pipeline. This is most effective for older plumbing systems that have a history of leaking.
  • In-Place Pipe Coating
    • If the plumbing system has a series of small leaks and it would be cost prohibitive or too inconvenient to dig up the slab, the in-place epoxy pipe coating is the best option.
  • PEX Replacement Piping
    • PEX stands for: crosslinked polythyrene. A proven replacement for copper piping, PEX piping is flexible, durable and has been successfully used for over 20 years. It won’t pit, scale or corrode and offers very good freeze-damage protection due to its flexibility.

Don’t let a slab leak get the best of you!

Early detection is key to preventing further damage. Remember, not all plumbers are qualified or even offer slab leak detection. Your best bet is to research the options available to you in your area, and hire an expert.


Image courtesy Flickr user gabriel amadeusAll images licensed for use under the Creative Commons.