Slab Leaks: Causes And Solutions

Read on to learn the leading causes of slab leaks and how to fix them

A slab leak is a homeowner’s biggest nightmare. It can wreak havoc on your home in a short time. The water that runs under the house erodes the soil in its way, thus putting strain on the slab and causing it to crack. A cracked slab allows the water to enter your home, and needs to be fixed right away.

Causes Of Slab Leaks

  • Leakage in the water pipe under a concrete slab foundation can result in a slab leak. Since water pipes are located beneath the house, these leaks may go unnoticed. Here are a few causes of slab leaks.

Expansive Soil

  • Expansion and contraction of soil is the common culprit behind slab leaks. As the water level of the soil changes, the soil expands and shrinks. The houses laid on clay and sandy soil foundations are more prone to soil shifting.

The constant movement of soil beneath the foundation can damage water pipes and cause them to crack. The leaking water leads to further soil shifting, thereby triggering a chain reaction that can quickly go unnoticed.

Type Of Plumbing Materials Used

  • The plumbing materials used can contribute to slab leaks. Cast iron and galvanized pipes are prone to rusting and clogging as they age. These pipes are commonly found in older homes. Modern homes use PVC (polyvinyl chloride pipe) and CPVC (chlorinated polyvinyl chloride pipe) as they are resistant to corrosion.

In addition, poor installation of pipes is another common cause of slab leaks. Pipes that are bent or dented during installation are prone to bursting when subjected to water pressure. The damaged areas become weak because of the abrasive property of the surrounding ground.

Friction And External Pressures

  • Water pipes rub against concrete, other lines, and materials during the course of their use. this creates friction and causes the structures to leak over time. Moreover, growing tree roots, earthquakes, soil erosion, and the underground stream can also contribute to slab leaks.

Fixing A Slab Leak

  • If you suspect a slab leak, have experts repair them for you. Professionals use modern equipment, including electronic listening tools, to pinpoint the leak’s location.

Pipe Rerouting

  • Rerouting is the best solution when a short section of the pipe is damaged. It can be worked around by installing a new plumbing line. Rerouting is a quicker and less disruptive solution. However, if the plumbing lines are encased in concrete and cannot be reached, re-piping the whole house is the best way to deal with the problem. Professionals install pipes in places that conceal and protect them, including attics, closets, etc. A little woodwork, such as crown molding, can hide the pipes.

Cutting Through The Slab

  • slab leaksWhen other options are unavailable, professional repairers break through the slab to reach the source of the problem. This method is the most disruptive and expensive. However, not all slabs are alike; some should not be cut through at all as this might lead to severe problems. In addition, cutting through the slab can cause inconvenience for homeowners.

While the work is being done, homeowners may have to live somewhere else. Moreover, the water supply is cut off, and the noise from jackhammers is deafening. There is dust and soil everywhere. The flooring in affected areas has to be replaced, thus making it an expensive method.


  • Tunneling is a slab repair method that helps salvage expensive flooring. The repairers dig working tunnels under a home to reach the source of the problem. In addition, it is the least expensive method and allows homeowners to stay in their homes while work is in progress.

If you have a leaking pipe in the concrete foundation, call us today at 877-727-2259. Our experts from Crack-X will assess the damage and provide necessary repairs. Crack-X is a structural repair company located in Maine and New Hampshire.

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