There are several signs that your windows may need to be replaced. Here are some of the most common signs: 1. Drafts and air leaks: If you feel drafts around your windows or notice air leaks when they are closed, it may be a sign that your windows need to be replaced. 2. Difficulty opening and closing: If you have trouble opening or closing your windows, it may be time to replace them. This could be due to warped frames or other damage. 3. Condensation: If you notice condensation forming between the panes of your double-paned windows, it may be a sign that the seal has failed and the window needs to be replaced. 4. Energy bills are higher than normal: If your energy bills have increased and you haven't changed your habits, it could be due to poor insulation from your windows. Replacing your windows with energy-efficient ones can help reduce your energy costs. 5. Visible damage: If your windows are visibly damaged, such as cracked glass or rotting frames, it's time to replace them.