If you have started to notice a lean, tilt, or buckling in some of your basement walls, then there are several issues that could be at work. Broadly speaking, however, the most common causes of bowing walls in any basement are hydrostatic pressure and foundation damage.
Hydrostatic Pressure
Hydrostatic pressure is a natural phenomenon caused by the weight of the water in the soil around a property. All homes are subject to hydrostatic pressure, and all homes are designed to withstand it. Of course, even the best designed property has a threshold for pressure. When hydrostatic pressure becomes too great for a home, it can cause bowing walls. This happens because of how it exerts lateral pressure.
Most basement walls are made of concrete, and concrete has a low tensile strength when compared to its compressive strength. Hydrostatic pressure tests its tensile strength by exerting lateral pressure, which is the main cause of a bowing wall. Many things can increase hydrostatic pressure around a home including poor drainage, heavy rainfall, underground water sources, and localized flooding.
Foundation Damage and Movement
Alternatively, bowing walls can be caused by foundation damage and movement. When this happens, it occurs because of the direct connection between basement walls and a property’s foundation. Any sinking, lateral movement, or fragmentation in the foundation can lead to an excess of pressure or a lack of support to the basement walls. This will then cause bowing, leaning, or buckling over time. Foundation movement and damage are also highly influenced by soil saturation.
Sudden flooding, heavy storms, or poor perimeter drainage can all contribute to foundation movement by making the soil unstable, marshy, or weak. In the cases of serious and dramatic flooding (for example, during a storm surge), the force of water hitting a home can also cause foundation movement. Any movement in your property’s structure poses a risk of cracking, fragmentation, and destabilization over time.