The frequency at which windows should be replaced depends on various factors like the type of window material, the quality of installation, and the climate in your area. On average, windows can last between 15 to 30 years. However, it’s essential to regularly inspect and maintain your windows to ensure their efficiency and performance. Signs that indicate you may need to replace your windows include drafts, difficulty opening or closing, condensation between panes, increased energy bills, and visible damage or rot.