Shattered glass is an obvious indicator of the need for window repair and replacement. There are far more common issues, however, such as leaks, cracks, and failures in the window pane material that are significantly less obvious than a baseball-sized hole. If not repaired or replaced quickly and correctly, both can leave you literally out in the cold. Locating a leak can be difficult, and when you do find the issue, what to do next can be even more challenging. Keep in mind the following common causes of inefficient windows. If you find one of these common issues, be sure to.