The Roots of Your Foundation Problems
What You Should Know About Tree Roots, Soil, and Your Foundation, and How To Prevent Damage in the Future
Most of us appreciate the value of a few trees in the yard. They provide shade and, visually, they break up the monotony of an empty lawn. But, trees are able to do what they do so well by virtue of a root system that can, under certain circumstances, present a potential problem for the structural integrity of your house’s foundation. What should you know about tree root damage that could help you mitigate disaster further on down the road?
- How tree roots affect your soil
- Concrete settlement and other factors that can cause foundation damage
- How you can prevent root damage
How Tree Roots Work and How They Affect Your Soil
Roots constantly extend themselves in search of water and nutrients in the soil to provide sustenance for the trees they support. This constant root movement also shifts around the soil that the roots are working within. Which type of soil your foundation sits on will generally determine the amount of shifting going on near or under the foundation of your house.
There are two main types of soil that will be affected by tree growth and root movement. The first type is soil that has a high clay composition. As roots extend further into clay soil, rather than shifting around, the clay compacts and becomes denser.
The other type of soil lacks the easily compressible clay and is composed primarily of looser dirt and rocks. This type of soil shifts around the root, allowing the root more freedom to move through it without compressing the dirt into densely packed soil.
Weather conditions will also affect the state of your soil and your root systems. A heavy rain season can leave your soil saturated and your roots expanded as they soak up water. Conversely, a drought can cause both roots and soil to contract. Both of these conditions – soil and root expansion and contraction – can damage the structural integrity of the soil.
It’s helpful to know what type of soil your foundation has been built upon as it can be a good predictor of what type of trouble you should keep an eye out for in the future.
Why does soil type, more so than the presence of actual tree roots, make for such a great predictor of potential damage in the future? Because, even for all of the grief we’re giving tree roots thus far, changes in the condition of the soil cause the most damage to a home’s foundation, usually in the form of settling concrete.
Tree root damage, generally, is damage inasmuch as it causes soil to shift, which in turn can cause concrete to settle. It can play a hand in foundation damage, but it generally isn’t the direct cause of it. Likewise, other factors like gardens, drainpipes, and poorly insulated basements can cause soil dehydration as well, resulting in concrete settling.
Sometimes, settling concrete is only a cosmetic problem; cracks forming across the surface of a foundation might not be anything more than unsightly. But, when soil expands and contracts, your foundation can shift and crack on top of it. Depending on how severe the settling is, the structure of your home could be compromised. Concrete settling can cause walls to sink and crack, support beams to shift, and ceilings to sink in.
Preventing Tree Root Damage
Before you go hacking down all your trees within a 50 ft radius of your house, consider some other steps you can take to prevent damage to your house. The first thing you’ll want to do is to actually confirm that you even have any roots near the foundation. Roots tend to grow horizontally and close to the surface, but when they run into the backfill soil near your foundation, they can begin to grow downward. You can sometimes find them by digging a foot or two under the surface of the soil within a few feet of the foundation. If you find a suspect root, you can cut it off. Installing a root barrier can prevent regrowth.
Of course, this assumes that your house already shares space with preexisting trees. What about planting new trees? Pick out a slow-growing species that isn’t known for its aggressive rooting proclivities. Oaks and sugar maples tend to grow slowly, while silver maples, willow trees, and elms tend to grow more quickly with deep roots.
How large is your yard? Since trees can grow roots up to three times its height, you’ll need to provide adequate space for the root systems. You might be wise to consider a different landscaping option: either smaller tree species or something else altogether.
Finally, and this was brought up earlier, it would benefit you to know what type of soil you’re working with. An analysis of your soil type and foundation status can provide some conclusive evidence as to whether or not tree root damage is a threat to your foundation.