Georgetown’s geology and climate are primarily to blame for the prevalence of foundation damage in the area. We’ll discuss the specific causes of under-home problems below and provide some insight into the effects each has on the concrete under your structure.
The Georgetown area is notorious for its many types of problematic soil. Interstate 35 offers a convenient piding line between the expansive clay soil to the east and the rapidly-draining soil to the west. Both soil types create several problems for concrete foundations.
The dirt to the east of I-35 falls in the Blackland prairie and is predominantly Houston Black. Houston Black is well-known around the world for its abundance of clay. Clay soil is problematic for three primary reasons.
The first issue is that it swells when it gets wet. When rain falls in Georgetown, the ground around your home expands and places undue stress on your foundation.
Unable to flex, the concrete can crack if the hydrostatic pressure from the soil becomes too intense. This movement often results in structural damage that is costly to repair.
The second problem is that the soil loses volume when it loses its moisture content. The ground under and around your home’s foundation can shrink at varying speeds, sometimes leaving portions of your foundation without adequate support.
The unsupported sections can crack off of your foundation and sink into the earth. Structural damage is a typical result of this differential settling.
Lastly, clay-rich soil in Eastern Georgetown can retain moisture more readily than typical dirt, leaving your concrete exposed to moisture for a prolonged time.
Water intrusion and the many associated issues are possible during periods of heavy or frequent rainfall in the area.
The soil west of I-35 has the opposite problem: it’s very sandy and drains rapidly. The loose soil can easily be eroded, sometimes creating voids under or around your concrete foundation.
These voids can contribute to differential settling, and they can also fill with rainwater and increase the risk of water intrusion.
Wet Season & Frequent Drought
Georgetown residents enjoy bright, sunny days for most of the year and experience just over 36 inches of rainfall annually. However, much of the precipitation occurs between March and May, as well as in October. These months bring approximately double the monthly average throughout the rest of the year.
The wet season in Central Texas leaves home foundations more prone to the issues with the already problematic soil. It saturates the clay soil in Eastern Georgetown, increasing the likelihood of excessive hydrostatic pressure, flooding, and water intrusion.
The concentrated precipitation also poses problems for the sandy soil west of I-35, as it promotes underground erosion, differential settling, and water and moisture problems.
These wet months are punctuated by arid weather, sometimes leaving the area without any rain at all for weeks or months at a time.
Drought conditions are common during these dry spells, and they frequently leave the soil without any moisture at all. When clay soils around your foundation dry and shrink away from the concrete, the risk of differential settling beneath your home is significantly higher.
Finally, there has been a substantially heightened construction rate in response to an influx of new residents into the Austin and Georgetown areas over the past decade or so. Unfortunately, some builders in the region take shortcuts to keep up with the increasing demand.
Improper soil preparation, backfilling, and compaction during the construction process can leave your home’s foundation at an even higher risk of problems related to the soil and weather patterns.
Specifically, damages from differential settling and excess hydrostatic pressure are more common when the ground has been inadequately prepared prior to foundation pouring.