Since glass is 87% of a window, it must have "SUPER" insulating qualities.
Single Glass- It provides only a thin barrier to the outside and can account for considerable heat loss and gain.
Double Glass- Better insulating value since multiple layers of glass increase the window's ability to resist heat flow.
Triple Glass - Even more energy efficient, usually with gas sealed in the frame, adds weight and expense to the window. Provides excellent sound-proof near airports and highways.
Clear Glass - Has been the traditional choice for windows but the development of better glazing has made possible the use of higher quality glass to help control heat loss and condensation.
Low Emissivity Glass (Low-E) - THis special type of glass has a special coating to reduce the heat transfer back through the window. This coatings reflect 40 - 70% of the heat that is normally transmitted through clear glass, while allowing the full amount of light to pass through.
Heath-Absorbing Glass - This contains special tints that allow it to absorb as much as 45% of the incoming solar energy, reducing heat gain. Some of the absorbed heat, however, passes through the window by conduction and re-radiation.
Reflective Glass - This has been coated with a reflective film and is useful in controlling solar heat gain during the summer. It also reduces the passage of light all year long, and, like heat-absorbing glass, it reduces solar transmittance.
BRISTOL SUPER TRIPLE-E - A-Plus with BR50 Spacer System feature 4 components that dramatically reduce energy loss:
1. Three layers of double strength glass.
2. Injection of ALPHA-10, a high performance odorless, colorless gas.
3. Four layers of Solar Ban 60 Low-E Coatings - Permits certain light waves to pass depending on the season:All year - Lets most visible light in so your home is bright and cheery while blocking up to 73% of harmful UV rays.
Winter - Lets in sun's short light waves. After entering, these waves turn into heat generating long waves, which are reflected back into the room.
Summer - Keeps out the long waves of light that otherwise would enter your home as troublesome heat.
4. All glass layers aresealed together with a "warm-edge" spacer system.