Texas has a wonderful pre-history, with mountains rising and eroding, a rich biota of life from sea creatures to dinosaurs. The spectacular geologic past is part of what makes Texas such an interesting state. Its part of why Texas has its rich oil deposits as well. For much of its history, Texas was partially underwater. For three hundred million years, much of Northern and Western Texas was covered by a shallow, brackish sea. The soils of around Dallas and Fort Worth have characteristics the resemble sea bed soils. They are made of very fine particles that have dried into clays, called smectite clays.
Dallas-Forth Worth Soils:
The special kinds of clays found in the soils in the Dallas-Fort Worth area are called expansive clays or expansive soils that have just the right arrangement of molecules to give them great water-absorption capability. When you add water to expansive clays, they swell dramatically, pushing upward and outward with a great force. Then as the expansive clays dry, they shrink back leaving air pockets or areas of potential ground collapse behind.
Expansive Soils in the West:
The problem of expansive soils is actually distributed in a wide belt along the western high plains from North Dakota and Eastern Montana following the Eastern edges of the Rocky Mountains to cover the entire state of Texas. Expansive soils are also very common in eastern North and South Dakota. However, there are two particular bands of problems that run through the Dallas-Fort Worth area.
Texas’ varied weather:
As anybody who lives in the area knows, Texas has a dry climate. However it does get significant rain. In fact, climatologists say that Texas has a more diverse climate than any other state with the possible exception of California. The atmosphere of Texas is in an almost constant state of flux. It’s this coincidence of the fine particulate sea-bed type smectite clay expansive clay soils and the frequent fluctuations between wet and dry conditions that cause the unique foundation problems in Texas, especially in the Dallas-Fort Worth area.
Irrigation to maintain house foundations:
A common method of preventing foundation cracks and basement floors lifting is to maintain a constant moisture level in the soil, not letting it dry out. Some home owners regularly spray their home foundations to keep the surrounding soil moist and in its expanded state. They argue that the use of water is less expensive than the cost of foundation repair.
However, in a time when water conservation has taken a high priority in the state and people are installing water conservation devices in their showers and toilets, the use of large water volumes to maintain the stability of housing foundations seems wasteful.
The other widely recommended approach is to construct a superior system of drainage to keep rain water away from the soils near the foundation.
Some engineers recommend replacing the soil near the foundation of the home with non-expansive materials that could allow for the expansion of surrounding soil. Others recommend adding calcium-based substances, such as calcium oxide, to the soil to reduce its expansion potential. Adding lime to the soil can draw the water out of the expansive clays. Other soil stabilizer products are also being developed.
A recent article in mySA, San Antonio’s Home Page puts some of the blame for foundation problems on shoddy building practices among some Texas builders. The article points to the “dismal record” when it comes to foundation construction in Texas. Texas law allows builders to construct minimally functional foundations that require large volumes of water used in the soils around the house in efforts to keep the foundations from failing. The article blames law makers for allowing the construction of foundations that require artificial irrigation to maintain stability. It maintains that sound construction practices could reduce the need for excessive foundation repair.
Perma-Pier Foundation Repair can help with your foundation problems in Dallas, Fort Worth, Houston and San Antonio. Please contact us to learn more.