What is Low-E Glass?
Low-E glass became available in 1979 and has been gaining in popularity ever since. It is treated glass that conducts visible light while controlling the passage of heat. Low- E stands for low emissivity. This glass is an energy efficient way to control the heat being allowed in and out of a home or environment. Different types of low-E glass are available to meet the needs of varying climates. Heat transferred through glass is measured by the U-factor. This is the rate at which glass conducts non solar heat flowing through it. The lower the U-factor rating, the more energy efficient the glass. Low-E glass allows visible light to pass through it but blocks heat-generating ultraviolet light, requiring less artificial heating or cooling to keep a room at the desired temperature. Low-E glass works by reflecting heat back to its source. All objects and people give off varying forms of energy, affecting the temperature of a space. Long wave radiation energy is heat, and short wave radiation
Windows , Low-e Glass . Try Windows & Exterior Walls for related news, articles, blogs, events and online resources. Today’s tip is about low-e glass, (the “E” stands for emissivity) which is being increasingly being specified for commercial windows because low-e glass can help save energy. Introduced in 1979, low-e glass works by preventing the sun’s heat energy from entering a facility through the windows. Low-e glass uses an ultra thin metallic coating on or in the glass to reflect the sun’s rays. There are two types of windows with low-e glass: Standard low-e and solar control low-e. Windows can come with either standard low-e glass, which has a visible transmittance of about .78 and a solar heat gain coefficient of about .54. Solar control low-e glass, generally used in hot climates, has the same visible transmittance, but with a solar heat gain coefficient as low as .4 – which is, on balance, a pretty good number. Solar control low-e glass works by blocking certain wavelengths of
In summer months, Low E glass keeps cool air inside while keeping hot air outside, and in winter, Low E keeps warm air in and cold air out. It also blocks up to 84% of the ultraviolet rays, which can fade carpets, draperies and artwork. In addition, the insulating glass unit is filled with Argon gas adding even more thermal efficiency. At HP Exteriors and Simonton Windows® we recognize energy efficiency is a key issue in the comfort and costs of running a home.
