Bowing walls can be recognized by spreading cracks, cosmetic damage, and visible unevenness in the surface of the walls themselves. This issue can be caused by a number of different factors, but the most common and likely are issues with a property’s foundation and issues in the soil.
Your property’s foundation is hugely important to its entire structure. Any damage to your foundation, no matter how slight, can cause serious issues throughout the structure, health, and safety of your home. As such, bowing walls are just one example of secondary damage which can occur as a result of foundational issues.
The most common foundational problems are subsidence and settlement. Both issues include sinking of some kind, either widespread (the entire home) or localized (just one portion of your home). Subsidence, for example, is a process by which the whole property, or a large portion of it, sinks into the ground while settlement is a process which causes chunks of a foundation to break away and sink into voids beneath the property. Either way, the main issue tends to be in the soil.
Most of the main structural issues in a property tend to be caused by problem soil in some way or another. Expansive soils, for example, contract and expand depending on their water content. Settlement is most often caused by dehydration of expansive soil, but can also be caused by soil washout and erosion.
Bowing walls, however, can also be caused by excessive soil saturation and the hydrostatic pressure which this can cause. The weight and pressure exerted by very wet soil, especially expansive soil, can overwhelm any wall over time, especially if it is made of poured concrete which has very low tensile strength in comparison to its compressive strength.