All About Slab Leaks and How It Affects Your Foundation

Many homes in Texas are built on a slab foundation. If you live in the eastern and central parts of the state, your slab foundation will likely be constructed on expansive clay soil. Leaky plumbing under a slab foundation built on expansive clay soil is the “perfect storm” for expensive foundation damage. On top of the problems of a damaged foundation, plumbing leakage under your foundation can also cause direct water damage to the inside of your home. Let’s get into slab leaks and how it affects your foundation in more detail below.

What Is A Slab Leak?

Plumbing is kept out of sight behind walls and under floors. If your home is on a slab foundation, then the plumbing hidden under your floor is located beneath the slab foundation. When this plumbing leaks, it’s called a slab leak.

How Does A Slab Leak Affect Your Foundation?

There are two ways that a slab leak can damage your foundation. If you have a big leak, it can quickly saturate the soil beneath your foundation. This waterlogged soil gets washed away and leaves behind a large void. The part of your foundation above this void then lacks support which stresses the foundation and causes it to crack and drop.

If you live in an area with expansive clay soil, then moisture changes cause this soil to undergo large volume changes. When its moisture content increases, it expands. When the soil dries out, it contracts. Therefore, another way that a slab leak damages your foundation is when a leak slowly penetrates into the surrounding soil. This increased moisture content expands the soil and creates a bulge beneath your foundation. The foundation then becomes stressed and cracks.

What hasn’t been mentioned yet are the causes of the plumbing leak beneath your slab foundation. This leak may be caused by old plumbing or by an installation mistake such as improper joins between the piping and fittings. However, sometimes the leak is caused by the soil expanding in response to prolonged wet weather or contraction during a drought. Even trees can send roots next to or underneath your foundation and extract moisture which in turn makes the soil contract. These soil volume changes may cause the foundation to distort and crack. This shifting and cracking of your foundation may then damage nearby plumbing and cause a slab leak.

Therefore, a slab leak can either be caused by bad plumbing, in which case it endangers your foundation, or it’s a symptom of foundation damage caused by something else such as a drought.

What Are The Symptoms Of A Slab Leak?

When water from a slab leak penetrates the foundation into your home, then you will notice water appearing on your floor with no “apparent” explanation. Sometimes this water manifests itself by spongy floors, distorted and buckling floor boards, and wet carpeting. Mold and mildew may also take hold and your home will have a bad odor. Other signs to look out for include unusually warm or even hot areas on your floor caused by a leaking hot water pipe.

Sometimes you may even hear the sound of constant running water. A water heater that is constantly running may indicate a possible slab leak. However, you should keep in mind that other problems can also cause your water heater to behave this way. An unusually high water bill is also an indicator of excessive water usage which may be caused by a slab leak.

If you notice the above symptoms, it’s important that you do something about it as soon as possible. Ignoring them will likely lead to yet more problems including possible foundation damage. Contact us at Perma-Pier Foundation Repair for a free evaluation.

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