Our Specialty

When heat or light energy is absorbed by glass it is either shifted away by moving air or re-radiated by the glass surface. The ability of a material to radiate energy is known as emissivity. In general, highly refective matierals have a low emissivity and dull darker colored materials have a high emissivity. All materials, including windows, radiate heat in the form of long-wave, infrared energy depending on the emissivity and temperature of their surfaces. Radiant energy is one of the important ways heat transfer occurs with windows. Reducing the emissivity of one or more of the window glass surfaces improves a window's insulating properties. For example, uncoated glass has an emissivity of .84, while PPG's solar control Solarban 70XL glass has an emissivity of 0.02.

This is where low emissivity or low-e glass comes into play.

Low-e glass has a microscopically thin, transparent coating - it is much thinner than a human hair - that reflects long-wave infrared energy (or heat). Some low-e's also reflect significant amounts of short-wave solar infrared energy. When the interior heat energy tries to escape to the colder outside during the winter, the low-e coating reflects the heat back to the inside, reducing the radiant heat loss through the glass. The reverse happens during the summer time. To use a simple analogy, low-e glass works the same way a thermos does. A thermos has a silver lining, which reflects the temperature of the drink it contains back in. The temperature is maintained because of the constant reflection that occurs, as well as the insulating benefits that the air space provides between the inner and outer shells of the thermos, similar to an insulating glass unit. Since low-e glass is comprised of extremely thin layers of silver or other low emissivity materials, the same theory applies.

The silver low-e coating reflects the interior temperatures back inside, keeping the room warm or cold. Similarly, Reflective Coated Glass is obtained by fusing a metallic oxide coating into the surface of the float glass as it is being made. Its pyrolitic coating makes the glass very hard-wearing and resistant to most severe weather conditions, aimed at satisfying structural requirements of engineers and creativity of architects. It is a highly reflective glass designed for any building where it is necessary to limit solar heat buildup and therefore reducing air conditioning cost. In the same manner, it limits light transmission, hence, reduces glare inside the building.