If you’re a landscaper, then you probably know that soil in the eastern half of Texas is known for its high clay content. What you may not realize, however, is what this can mean for homes and structures. As clay soil shrinks, it dries out; and when it gets wet, it expands. This shrink/swell action can generate enough force to cause major damage to walkways, building foundations, and patios.
You can control soil expansion in three basic ways:
- Keep water off the soil – Collect rainwater from roofs in gutters and pipe it away from buildings. You should also direct water away from structures and soil should slope away from buildings for at least five feet out from a wall. Make sure trees and large shrubs are at least ten feet from buildings since roots suck moisture from the soil which can cause shrinkage and collapse.
- Mix lime or other anti-expansion products into the soil – This is an especially good thing to do for the soil that’s under a building’s foundation. However, you’ll need to keep all irrigation at least five feet away since water will leach lime and other materials out of soil.
- Replace clay soil with a non-expansive one – You can remove clay soil and then replace it with severely compacted layers that have lime added to them. Alternatively, you can have non-expansive soil brought in from someplace else and then make the switch. You’ll still have to make sure that you don’t plan anything within five feet of any structure where the soil has been so replaced.
Effective irrigation begins with an understanding of the kind of soil to be watered.
