What's normal settling, and what's a sign of real trouble?
Our home is nine years old, and recently we have observed cracks above the doorframes that are about 10 inches long. The doors don't close, and our sliding doors are having problems, too. How can we tell the difference between cracks caused by normal settling of the house and cracks that indicate a structural problem?
— Eleonore, Williamsburg, VA
Tom Silva replies: Most houses settle somewhat after being built, as the soil compacts under the foundation and the framing dries out. Normally this results only in hairline cracks at wall junctions or between sheets of drywall. But any cracking that prevents doors or windows from operating isn't normal. Any crack that appears suddenly isn't normal. And any crack that continues to grow in width or length isn't normal. All of these situations indicate potentially serious problems that should be investigated immediately by an experienced remodeling contractor or a structural engineer.