What is Low E Glass Windows?
One of the biggest buzz words in the replacement window market in the Buffalo, NY area is "Low E Glass", but just what is it? Low E is short for low emissivity. Emissivity is a measure of how much radiant heat is transferred by the glass surface. The less radiant heat transferred, the better. This window glass product is coated with a thin, transparent layer of silver, tin, or zinc sandwiched between layers of metal oxide. During the winter, it keeps the heat in, and during the summer, it keeps the heat out.
There are 2 types of low E glass, hard coat and soft coat. Hard coat is an older process where the coating is applied when the glass is still molten. Soft coat low E is applied after the glass is manufactured. Soft coat is about 20% better in reflecting radiant heat, and is the preferred choice of the wise consumer.
The panes of glass in double pane and triple pane windows are usually filled with argon or krypton gas. These gases are heavier than air and do not move around as much. This does not allow heat to be transferred as easily through the window glass. Krypton gas is a little better than argon gas at doing this, but is quite a bit more expensive, and is not used as often as argon gas.
Because of the warmer temperature the interior pane of glass will maintain in a double pane window, there will be less condensation that forms on your windows. This will help your house maintain a higher humidity level for greater comfort. The condensation that forms on your windows is frequently the cause of great damage to your sashes.
Another advantage of Low E glass is the fact that it will block twice as many ultraviolet light rays as ordinary clear single pane glass. This will reduce the fading that the sun causes on your drapes, carpets, and furniture.