Expansive Clay Soils in Texas: Locations, Risks, and the Cost of Damage

Expansive Clay Soils in Texas: Locations, Risks, and the Cost of Damage

Expansive clay soil posses a serious threat to homes, infrastructure, and landscapes across

Texas. Known for their ability to swell with moisture and shrink during dry conditions, these soils

can cause significant structural damage. For homeowners, builders, and public officials alike,

understanding where expansive clay soils are most common in Texas—and the financial

impact they can cause—is key to protecting investments and mitigating damage.

In this blog, we will explore the regions in Texas where expansive clay soils are found, the

risks they present, and the staggering dollar amounts associated with damage caused by these

soils.

What Are Expansive Clay Soils?

Expansive clay soils contain a high percentage of minerals like montmorillonite or bentonite,

which have the unique ability to absorb large amounts of water. When wet, these soils swell,

expanding significantly, and during dry periods, they shrink and crack as the moisture

evaporates. This constant movement places pressure on structures such as foundations, roads,

and pipelines, leading to costly damage over time.

Where Are Expansive Clay Soils Found in Texas?

Texas is home to some of the most expansive soils in the country, with large portions of the

state covered by soil types that are prone to swelling and shrinking. The regions most affected

by expansive clay soil in Texas include:

1. Dallas-Fort Worth Area: The DFW metroplex sits atop vast layers of expansive soil,

particularly in suburban areas. Known as the Houston Black clay and Austin chalk

formations, these soils expand rapidly with moisture and shrink significantly during dry

spells.

2. Central Texas: Cities such as Austin, Waco, and San Antonio are all built on top of

expansive clay known as the Eagle Ford Shale. This soil type, combined with Texas’;

unpredictable weather, causes constant soil movement, leading to foundation damage.

3. East Texas: Expansive clays are also prevalent in the Blackland prairies of East Texas,

affecting areas like Tyler and Longview. The soils here contain high concentrations of

clay minerals, and the humid climate further contributes to their swelling.

4. Houston Area: The Houston region is built on a mixture of expansive clays, particularly

the Beaumont clay, which is notorious for foundation problems. The city’s coastal climate

results in frequent shifts between wet and dry conditions, causing extreme soil

movement.

5. West Texas: While West Texas is generally drier, expansive clay soil still poses a threat,

particularly in the Permian Basin. Even small amounts of rainfall can cause swelling in

the region’s clay soils, which can still cause foundation and infrastructure issues over

time.

The Financial Impact of Expansive Clay Soil Damage

The financial impact of expansive clay soil in Texas is staggering. Each year, these soils cause

billions of dollars in damage to homes, roads, pipelines, and other infrastructure. Here’s a look

at some of the ways expansive soil can cause costly problems:

1. Home Foundation Damage: One of the most common forms of damage caused by

expansive soils is to home foundations. As the soil beneath the foundation swells and

contracts, it causes cracks in the foundation walls and floors. According to estimates,

homeowners in Texas spend between $4,000 and $12,000 on average for foundation

repairs due to expansive soil movement. In severe cases, the cost can exceed

$20,000.

2. Infrastructure Repairs: Expansive clay soil also causes significant damage to roads,

bridges, and pipelines. Roads built on expansive soil are prone to cracking and

buckling, while underground pipelines can be damaged by shifting soil. The Texas

Department of Transportation (TxDOT) spends millions annually on road repairs

because of expansive soils. Nationwide, it is estimated that expansive soil causes

between $2 billion and $15 billion in infrastructure damage each year, with Texas

bearing a large portion of this cost.

3. Insurance Claims: Many homeowners in Texas file insurance claims for foundation

damage caused by expansive soil. Unfortunately, standard homeowners' insurance

policies typically don’t cover damage from soil movement, leading to out-of-pocket

expenses for repairs. The Texas Department of Insurance reports that foundation

repair claims related to soil movement are among the most frequent and costly types of

homeowner claims in the state.

4. Commercial and Public Buildings: Expansive soil damage extends beyond homes to

commercial buildings, schools, and hospitals. These structures, like homes, are

vulnerable to foundation cracking and structural damage caused by soil movement.

Repair costs for large commercial buildings can reach hundreds of thousands of

dollars.

Preventing Expansive Soil Damage in Texas

Given the prevalence and risks of expansive clay soil in Texas, taking preventive measures is

essential. Here are some steps homeowners and builders can take to minimize damage:

 Soil Testing: Before building a home or commercial structure, soil testing can determine

whether expansive clay soils are present. This allows builders to take necessary

precautions such as soil stabilization.

 Clay Soil Stabilization: One of the most effective ways to manage expansive soil is

through chemical soil stabilization. Chemical Soil Stabilization can reduce the soils’

ability to shrink and swell, making it more stable for building.

 Drainage Systems: Proper drainage around homes and structures can help control

moisture levels in the soil, reducing its tendency to expand and contract. French drains,

gutters, and sloped landscaping can all help direct water away from foundations.

 Regular Monitoring: For homes already built on expansive soil, regular monitoring of

the foundation for signs of cracking or shifting is essential. Catching problems early can

reduce repair costs.

Conclusion

Expansive clay soil is a hidden yet serious threat to homes and infrastructure across Texas.

From the bustling cities of Dallas and Houston to rural areas, these soils can cause significant

and costly damage. With billions of dollars spent annually on repairs, it’s important for

homeowners and builders to understand the risks and take preventive steps.

By stabilizing the soil, improving drainage, and monitoring structures for signs of movement,

Texas residents can protect their investments and minimize the financial impact of expansive

soil damage. Awareness and action are key to reducing the long-term costs associated with

these challenging soils.