Cracks of varying widths and angles are common concrete slabs. Most of these cracks are small and harmless. Some cracks that are longer and wider may have more of an impact on the slab floor.
Concrete cracks generally occur due to either shrinkage, expansion, or settlement. When the concrete is poured, if it dries too quickly the slab shrinks from the water loss and it will exhibit cracks that are usually random in direction or located along a control crack joint. These usually do not impair the performance of the slab but look unsightly and can eventually allow water seepage. Expansion cracks occur when the slab heats up and expands into another slab, wall or other obstruction. The resulting forces that resist the expansion can cause cracks in the slab. Settlement cracks occur when the soils beneath the slab were not properly graded and prepared prior to the pouring of the slab or from erosion beneath the slab itself.
Do I Need to Fix This?
All of these cracks need to be monitored and assessed for water and insect infiltration and future slab failure. Shrinkage cracking and checking due to quick curing of the concrete are generally cosmetic in nature, but can grow over time and should be monitored. Expansion and settlement cracking usually will continue to worsen over time and should be evaluated by a concrete repair professional who can provide options for restoring your slab for ultimate performance and to mitigate water and insect intrusion.
There are multiple, plausible solutions for cracks in slab floors. Some solutions are smaller in scale, others can be intrusive and a larger scaled project. For a customized solution, contact a trained profession for an assessment fitted to your situation.