September 12, 2018

Is Your Home Built On Expansive Soil?

In order to provide structural protection to your expansive soil based property, you need to keep the following in mind: Test and classify soil, design to reduce moisture content and insulate against volume changes, maintain a proper moisture environment.

A person stands next to a brick building

It’s done. You’ve purchased your dream home, taken ownership of the keys, and moved all of your furniture in. Now the hard part begins.

Now you get to worry about the many different things you need to do to protect your home from cracks and foundation damage. A major risk factor for homes in many parts of the country is foundation movement as a result of expansive soil. The amount of movement at a given location depends upon the reactivity of the soil, but it can also vary depending on the weather, the time of year, and even the location of your home on the lot.

Before we plunge into the details of how to cope up with these soil conditions, let’s first explain what expansive soil is.

What is Expansive Soil?

A type of “clay soil,” expansive soil shrinks or swells when it is exposed to moisture.

These soil include a high concentration of minerals that include smectite clays that have a tendency to absorb water. The more water it absorbs, the more it increases in volume. Expanding 10 percent in volume is not unheard of for these types of soils.Not only does this create pressure within the soil itself, but it can also exerts enough force to damage the foundation of any building, sidewalk, concrete slab, patio, or other structure built on top of it.

What Kind of Damage Does Expansive Soil Cause?

The list is long.

Structural damage like cracked foundations, basement walls, and floors are some typical signs that you have expansive soil. In fact, if the structural damage is significant, it can even cause damage in upper floors and roofs.That’s just the swelling, though. Once expansive soil dries out, it shrinks. This shrinkage can remove some of the foundational support of the building and causes further structural damage.

What Should Homeowners Do About Expansive Soil?

Since the repeated contraction and expansion are the cause of structural damage, controlling the expansion is the cause of the damage, limiting that movement is the goal of any effective treatment for expansive soil.

That’s the good news.The bad news is that, once a structure has been built on expansive soil, there is generally no preventing the problem. The foundation has to be reinforced and, often, the entire building will need to be replaced.

For homeowners, the best course of action if a good defense. Keep an eye out for structural damage, watch your walls, and call in the professionals quickly if you suspect expansive soil on your property.It is possible to build a home safely on expansive soil as long as you can maintain stable moisture. In order to provide structural protection to your expansive soil based property, you need to keep the following in mind:

  • Test and classify soil
  • Design to reduce moisture content and insulate against volume changes
  • Maintain a proper moisture environment

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