Vinyl Window Frame
Vinyl window frames made their first appeared in Germany during the 1950s as wood, aluminum, and steel were scarce after World War II. They gained popularity in the United States during the energy crisis of the 1970s. Vinyl window frames are made from polyvinyl chloride (PVC) with ultraviolet light (UV) stabilizers that prevent solar light from degrading the material.
Look for windows with other energy efficiency features, such as multiple panes, argon-filled and Low-E coatings.
The insulating value of windows is usually rated by the whole window U-factor and the lower the value, the better. Energy Star rated windows should have a U-factor of 0.27 Btu/hr-sq ft °F or less for Northern climates.
Vinyl window frames are cost-effective, energy-efficient, do not need to be painted or refinished, are low maintenance, and are highly recyclable.
Early window frame materials included wood, iron, and lead. Of those, wood is still used today, and metal frames have graduated to aluminum, stainless steel, and coated steel, with insulation breaks to cut heat loss. Lead is no longer commonly used in window frames.