Simply put—Foundation damage is caused by soil movement. The three directions the foundation can move is: up, down, or inward from the exterior soil pressure pushing against your concrete foundation wall. Your foundation can experience all three types of movement, – at the same time. The potential movement of your foundation depends upon the soil conditions around your home. These soil conditions range from not expansive to very expansive depending upon where you live. The average potential for soil expansion is around four inches, but can be as high as twelve inches in some areas. This amount of movement can severely damage your foundation and home. It is very important to maintain the integrity of your foundation.