What Makes Windows and Doors Energy Efficient?
We’ve all heard of ENERGY STAR® and know that energy-efficient windows save on heating and cooling costs. But do you know how your choice of options affects a window’s energy efficiency? Here are some of the elements of your window that help make it energy efficient.
FRAME AND SASH MATERIALS
Companies use a variety of framing materials to reach energy efficiency, including vinyl and wood. Companies that manufacture vinyl windows have low maintenance vinyl frames, and the way they are constructed helps the overall window provide excellent thermal insulation. But remember, not all vinyl is equal – thicker vinyl walls with multiple air chambers improve thermal performance. Wood windows manufacturers create wood frames which provide excellent thermal insulation values and are the right choice for homes that have historical features. A Perfect View Construction carries wood windows are clad with aluminum to reduce maintenance on the exterior.
Weatherstripping is another element that adds to energy efficiency by protecting against air leakage. The lower the air leakage, the better the energy efficiency. The average vinyl window has an air leakage rating of .3 cubic feet per minute (cfm).
Low-E refers to a special coating applied to a pane of glass. By reflecting infrared light, Low-E helps stop temperature transference. In addition to its energy-saving properties, Low-E glass helps reflect UV rays that lead to fading color on interior furnishings.
The glass itself is a terrible insulator. Older windows with only one pane of glass allow heated or cooled air to escape more rapidly. Two panes of glass insulate much better than a single pane because of the air space between the two panes. Triple pane adds another air pocket, enhancing the insulation value even more. Adding gas between the panes improves energy efficiency dramatically.
The air, between the glass panes, works as an insulator because air is a poor conductor of heat. Some energy-efficient windows go one step further and have argon or krypton gas injected between the panes of glass. Still wholly transparent to the eye, these gasses are heavier than air and provide even better insulation. In the case of seal failure causing leakage, both argon and krypton are odorless, transparent, and non-toxic, so there is no worry.
The spacer system offers insulation to the edges of the glass, the area that is most vulnerable to temperature transference.
The American Architectural Manufacturers Association (AAMA) has a history of industry leadership and the development of window and door performance standards. Milgard windows carry the AAMA Gold Label to show they have met their strict requirements, which are tested and certified by a third party. This rigorous testing includes water penetration, air leakage, structural integrity, and Forced Entry Resistance.