Established by the US Department of Energy and the Environmental Protection Agency, the ENERGY STAR program defines thermal efficiency levels for three different climate regions of the country. The regions are divided by their need for reducing heating costs (northern), reducing cooling costs (southern), or providing the best balance of savings for both (north/central and south/central). Products receive an ENERGY STAR label for the region or regions for which they qualify. It’s easy to remember that WD USA’s windows with the SunPro glazing systems have qualified for the ENERGY STAR label in every region.
NFRC label lets you compare
The National Fenestration Rating Council (NFRC) sets standards for reporting energy
performance information based on independent testing, so you can compare windows with confidence. In face, this is the data that the ENERGY STAR ratings are based on. When you compare, you’ll see that WD USA’s windows are among the leaders in thermal efficiency. What’s more, they transmit a high level of visible light for a natural view, and they beat industry standards for air leakage by 100 percent. Learn the measurements that matter:
U-value measures heating efficiency.
This is a window’s ability to block the flow of heat through the glazing system, and retain the heat in the room. The lower the U-value, the better the efficiency. For an easy reference, WD USA’s proprietary SunPro Low “E” glazing system with a low-conductance spacer and argon gas between the panes has a U-value of 0.30, so it is almost twice as efficient as an ordinary double-pane glass system with a rating of 0.50.
Solar Heat Gain Coefficient measures cooling efficiency.
This is a window’s ability to block the infrared heat from the sun, and maintain a cooler temperature in the room. The lower the coefficient, the better. WD USA’s SunPro system has a rating of 0.30, so it is almost twice as efficient as an ordinary double-pane glass system with a 0.58 rating.