Energy-efficient window film targets the glass, usually the weakest point in a home's thermal envelope. By reducing the solar energy passing through the pane, film lowers the heat load that builds up in sunlit rooms and eases the work your cooling system has to do to hold a steady temperature. That same treatment cuts glare and filters ultraviolet light, so comfort improves on more than one front. For many Tallahassee homes it is a far less disruptive option than replacing glazing, since the existing windows stay in place. The effect depends on which film is used and on the glazing it is applied to — single pane, double glazed, laminated or already coated glass all behave differently — so identifying the existing glass is the first step. A Kepler dealer can advise on what suits your windows before anything is specified.