As the water in concrete evaporates, the cement and gravel in concrete dry into a hard slab. Cracks in your concrete are often a byproduct of this drying process, and don't always indicate a structural concern. It is imperative to fix these cracks as soon as you find them, as structural problems may occur if your foundation cracks multiply and grow. If your home has sunken or unlevel floors, you may have a problem with your foundation. Your property’s value and safety will be compromised by such structural problems, so hire a foundation specialist to help you diagnose and fix them.