by C. Sherman Henes and Cassi Henes
Most soil in the Front Range can be classified as a swelling soil. This means that the soil contains a high percentage of certain types of clay that absorb vast quantities of water. This can cause the soil to expand 10% or more as moisture enters it, usually during winter snow melt and spring run off. The soil can then exert pressures of 20,000 psi or greater on foundations, slabs, and other structures. Now, this soil also contracts when the moisture evaporates during our hot summer months, causing extreme differences in the pressure being generated on your foundation, driveway, or patios.
The way that our soil dries also important to understand. In Colorado, we have 255 days of sun on average, which tends to dry out the top layers of soil. With clay, the top layers will become hard and impermeable and the bottom layers will remain moist. This can explain why you might have a moist, musty basement, but be having trouble keeping your lawn from burning. It’s also one of the reasons why we experience flash flooding in Jefferson County.
If you’re noticing that your basement walls appear to be bowing or cracking, Peak Structural Specialists would be happy to sit down and go through your options with you. Many times, a solution can be as simple sprinkler positioning or grading. We’re here to help you resolve these problems, so please contact us today for a no obligation consultation and estimate.