Windows can present an efficiency challenge in most homes, and energy-efficient window treatments and coverings help close the gap. Heat is both gained and lost through window glass. Summer sun radiating through windows carries an abundance of solar energy into the house, making your A/C run longer to meet thermostat settings. During winter, indoor heat radiates out through windows, increasing heating costs. New windows with heat-resistant glazing are an expensive option. However, homeowners also can reduce heat gain and loss by utilizing these cost-effective, energy-efficient window treatments and coverings:
- Awnings provide simple shade that can cut solar energy infiltration by 65 percent on south-facing windows and more than 75 percent on the west side of the home. Today’s synthetic fabrics reflect more sunlight and resist deterioration better than canvas.
- Blinds are effective at blocking summer sun and the heat energy it carries, reducing it by as much as 45 percent when closed. They’re less effective at reducingheat loss in winter.
- Draperies can be effective heat-stoppers if they’re the right color and hung close to the window. Heavy, light-colored drapes with white backing reduce summer heat infiltration by up to one-third. Drapes closed at night also can cut heat loss by 10 percent – regardless of color.
- High-reflectivity films applied to the glass itself reduce heat gain year-round. The silver, mirrored films reflect the most heat energy, while the more transparent or colored varieties are less effective. Films also are most efficient when applied to east- or west-facing windows that receive the most hours of daily sun exposure. Interior light and outside visibility also are affected in all seasons, and the reduction of winter heat gain can be a drawback of reflective films if you rely on the sun’s heat in winter to help warm rooms.
- Mesh screens are made of a fine, tightly woven polyester that’s almost invisible to the naked eye. Mounted on the outside of the window, these screens cut heat gain by diffusing solar energy instead of reflecting or blocking it.
For more information on energy-efficient window treatments and coverings in the Baltimore area, please contact us at Griffith Energy Services, Inc.
Written by Kevin Spain