Not necessarily. Oklahoma has a lot of clay in the soil, and it is common for the soil to shift during extreme weather, especially our hot summers. This shifting over time can cause foundations to shift, resulting in cracks. In addition, or high winds can cause walls to shift and crack even if the foundation is solid.
There are primarily two ways cracks develop in the exterior walls.
Much of central Oklahoma has clay based soil, which expands and contracts depending on weather and soil moisture content. And many Oklahoma homes are built using concrete stem walls and slab foundation. When the clay expands and contracts, the concrete foundation and slab can end up with cracks. To deal with these cracks, piering companies will drive piers into the ground beneath the slab, shoring up the home and helping to stop the movement of the concrete slab and foundation.
Sometimes the concrete slab can crack while the foundation does not. This is not as worrisome since the home is primarily supported by the foundation. When looking for cracks, a qualified and experienced home inspector will look for cracks in the actual foundation. These may require piers, while cracks in the concrete slab alone may not need piering. Piers are easily installed and cost around $1,000 per pier, and a typical home may take 2-10 piers to shore up a cracked foundation.
Another major cause of cracks in Oklahoma homes is our strong winds. It is not unusual to experience 70-100 mph winds at least once per year. While most homes are designed to withstand these straight line winds, they may shift slightly and form cracks near windows, garage doors or large, flat sided walls. We often see these around garage door openings, since the wall at the garage door opening is small and does not provide much structural support. These types of cracks do not benefit from foundation piering.
If you have questions about exterior wall cracks, then you will want an experience structural engineer to examine the home and provide recommendations on repairs if necessary. Sometimes repairs are not necessary, but other times they can run tens of thousands of dollars. You will want to know about any needed repairs before agreeing on a sales price.