Window technologies have advanced dramatically and prices for these windows have dropped significantly. Look for windows with the ENERGY STAR label. Heat gain and loss through windows accounts for up to 50% of a home's heating and cooling needs. Many technological improvements have been made in recent years that have advanced the insulating quality of windows including: Advances in window technology such as double glazing and low-e coatings substantially reduce heat loss and gains. Look for ENERGY STAR or National Fenestration Roofing Council (NFRC) labels to be sure you are getting high-efficiency windows.

(Energy Star website)

The WDMA Hallmark Certification Program gives specifiers a method of identifying windows, doors and skylights which are manufactured in accordance with WDMA standards. The WDMA Hallmark is considered a mark of excellence among architects, contractors and other specifiers and is accepted industry-wide. WDMA Standards are referenced by HUD/FHA in their Minimum Property Standards and by many other government agencies in their construction specifications.

(WDMA website)

National Fenestration Rating Council (NFRC) is a non-profit, public/private organization created by the window, door and skylight industry. It is comprised of manufacturers, suppliers, builders, architects and designers, specifiers, code officials, utilities and government agencies. NFRC provides consistent ratings on window, door and skylight products.

(NFRC website)

See Sun's Performances Ratings

Sun also participates in the following certification programs and testing standards:

SIGMA (Insulated Glass Manufactures Association)
ASTM