When you consider energy efficiency, perhaps the most critical part of any window is the insulating glass system. It only makes sense: the glass has the largest surface area.
To understand how windows can help, you must first understand that energy is lost through windows in three major ways: conduction, convection and radiation.
The framing of all Windgate windows is made from vinyl, a natural insulator. To prevent energy loss through conduction, all insulated glass units utilize Duralite© “warm edge” technology. Using a low-conductance spacer, this method assures maximum resistance to energy flow.
Energy can also be lost through natural convection currents that can form within the insulating glass. That’s why Belmont® glass is 3/4″ thick, shown by government testing to be the optimum dimension to prevent these convection currents.
Radiation occurs when long wave heat energy moves toward cold areas.
The most effective barrier to radiation is an optimal special Low “E” coating, a standard part of our InnovativE® glass.
This special coating actually reflects the long wave radiation back to its source.
This is important to understand, as radiation affects energy consumption, no matter what part of the country you call home.
The concerns of home owners in the North are quite different than those in the South.
In the North,where heating is a concern, glass must allow maximum solar gain, while preventing heat loss.
NFRC Ratings with Low E and Argon-Gas Fill
| Product Series | Operating Style | U-Value w/ Low-E & Argon Gas | Solar Heat Gain Coefficient | Visible* Light Transmission |
|---|
| Belmont | Double Hung | 0.27 | 0.28 | 0.53 |
| Belmont | Single Hung | 0.27 | 0.29 | 0.56 |
| Belmont | Double Horizontal Slider | 0.27 | 0.28 | 0.54 |
| Belmont | Single Slider | 0.27 | 0.29 | 0.54 |
| Belmont | Picture Window | 0.27 | 0.30 | 0.57 |
| Belmont | Casement/Awning | 0.27 | 0.27 | 0.51 |
| Belmont | Patio Doors | 0.27 | 0.30 | 0.57 |
*Architectural drawings and structural tests/ratings available upon request
