A window may be made insulative through the addition of sealed, properly suited coverings. Window coverings are commonly considered blinds, but they are no longer restricted to only blocking the passage of light into a room. Blocking heat passage with a movable item (open/close), such as a window covering, allows a home or business owner to reap the benefits of high efficiency (insulative) windows without the expense. Multiple layers can be integrated into the system to give immense flexibility to the user; allowing solar light to fill a room while restricting heat (reducing summer air conditioning and lighting loads), restricting light and heat passage (dark room or theater conditions) or restricting light passage while allowing heat passage (dark room with comfortable outside temperature). The remaining option (free light and heat passage) is accomplished by any or all layers to expose the glass surface.