University of Florida

Home > Health and maintenance > Solve problems > Roots damaging buildings

Roots damaging buildings

oak tree very close to house

First check to see if tree roots are causing the problem. Do this by excavating soil from next to the foundation to determine if roots are under or near the building. Many roots simply grow to the foundation and are deflected to grow laterally along the foundation. They often grow around the building but not under it.

Building foundations can crack without help from trees. Buildings set on clay soils can crack in dry weather as soil shrinks. Sometimes the clay is several feet beneath the sandy top soil. Add water to the soil around your home to help raise the soil back up. Some of the cracks in the walls may close as a result of this treatment.

Tree roots near a building could cause damage in two ways:

  • raising up the building
  • shrinking the soil by extracting water from it. Soil shrinkage and the resulting building subsidance is most common in clay soil.

Possible solutions: Try adding water to the soil next to the foundation before attempting to solve the problem by cutting roots. Soil (especially if the clay content is high) may swell back to its original level and close the cracks. If the cracks appear to be the result of lifting, then you might consider cutting roots. Caution is advised as cutting large roots can result in trees toppling over. Roots larger than about one inch are considered large.

See: more on cutting roots.