You may see “step” cracks angled toward the adjacent walls in concrete block foundations, or you may see angled vertical cracks in poured concrete walls.
First, there are shrinkage cracks. When concrete cures, it shrinks as the water evaporates from the wet concrete. You may see small cracks in the mortar joints on block walls, or you may see vertical cracks in the seams between two section of poured walls.
Second, forces pushing the walls from the exterior may cause movement inward. These forces are typically caused by expansion of the soils when they absorb water. You may see a long horizontal crack located about mid-way down the concrete block walls, or you may see a vertical crack angle toward the adjacent walls on poured concrete walls.
Third, unstable soil under the foundation can compress and the foundation could begin to sink downward into the compressed soil. Fill soil, very wet soil, and very dry soil, are all subject to compression, as the weight of the foundation sinks into them. You may see “step” cracks angled toward the adjacent walls in concrete block foundations, or you may see angled vertical cracks in poured concrete walls.
A professional structural repair company can diagnose more specifically what is causing a foundation cracking problem. Using laser levels, measurements can be taken to determine what types of services may be needed to resolve the problem.
Once diagnosed, engineered procedures can be completed that will stabilize the foundation (to keep it from continuing to move), and many times, to straighten or level walls that have moved inward, or have sunk downward.
Go to ohiobasementsystems.com for more information on the services provided to diagnose and repair these problems.