Foundation cracks can spread over time, especially during temperature fluctuations or increased moisture (humidity, precipitation, etc). The cracks may get longer and wider, further compromising the structural integrity of your home or business. Water may seep through foundation cracks and cause moisture damage, including the potential growth of mold or mildew. The shape and behavior of your foundation cracks can help point to their cause.
Horizontal cracks travel from wall to wall and are indicative of uneven pressure placed on the foundation wall. This kind of strain can cause tilting and bowing of foundation walls over time.
Diagonal cracks indicate uneven settling over time. The crack can travel diagonally along the foundation as distinct parts of the home settle at different rates.
Stair-step cracks are similar to diagonal cracks because they can also be caused by differential settlement. Soil pressure can also cause these cracks to form along mortar joints, giving it that stair-step appearance.