Age is an important consideration as windows become less efficient with time, and we encourage area homeowners to install energy-efficient windows proactively based on the expected lifespan of their current windows. You should also watch for signs that your windows are wearing out sooner than expected. Draftiness that cannot be corrected with new weatherstripping is a telltale sign. You should also replace windows that are difficult to open or close or no longer secure, and windows with non-superficial damage to either the frame or glass should be replaced as soon as possible.