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Sweetwater Plumbing Blog

What Causes Slab Leaks?

You may have heard about slab leaks before and not understood exactly what it meant. In plumber lingo, a slab leak is a pipe leak that occurs under a concrete or granite slab. Usually, it refers to a leak that happens in the foundation of a house, although this leaking can occur in other places. But as a homeowner, the type you’re most likely to encounter is the concrete foundation type.

How do these leaks start?

There are many different ways for leaking to start in pipes down in a home’s foundation. The most frequent cause is a shift in the soil below the foundation—something that often occurs in California because of earth tremors. These ground shifts, even if tiny (such as quakes you might hardly notice), will result in the concrete slab shifting as well, and this can easily cause one of the pipes in the slab to break. Even changes in moisture level can make the clay under a home expand and contract, which may be enough to shift the foundation and damage the piping.

Another cause of these leaks is corrosion. Although most plumbing today is made from corrosion-resistant copper, there are chemicals that get into the water supply that trigger a specific type of corrosion that weakens copper and leads to leaking.

Why are slab leaks a problem?

Any plumbing leak is a problem because it wastes water and leads to water damage, which is expensive to fix. But slab leaks present a number of specific problems. They often lead to the development of mold below a house, and this creates an indoor air quality problem if allowed to go on long enough. Slab leaks can also lead to significant damage to the lower structure of a house, rotting away wood supporting beams.

However, you don’t have to let the situation get that bad: as soon as you notice a rise in your water bills that you cannot explain, call our plumbers to perform slab leak detection and see if you need repairs done.

Sweetwater Plumbing serves Fullerton and throughout Southern California. We don’t charge by the hour, we charge by the job!

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