Why are there cracks in my concrete slab foundation?

Three reasons for cracks in a concrete slab foundation:

  1. Stress at an outside corner can cause a wedge shaped corner to crack.  This is not a problem.
  2. Surface cracks may have occurred as the cement was curing. This is not a problem.
  3. The crack could be indicative of a foundation problem.  You will need to call a foundation repair company such as Granite for a foundation evaluation.   Such inspections are usually free to the property owner when performed by a foundation repair company.