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Reducing Heat Gain Through Glass

In Temperature Control by brandon

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Heat from the sun is still in the form of radiant energy when it first hits the glass in a window. As it strikes each of the glass surfaces in a window some of the energy is reflected (still radiant), some is absorbed by the glass (no longer radiant), and the rest is transmitted through the glass and into the room (radiant). To reduce the amount of heat entering the building we must either absorb or reflect a portion of that transmitted radiant heat.

Reflection is preferable to absorption for the following reasons:

  1. Reflection gets the heat energy quickly away from the building for greater effect and
  2. Absorbing the heat causes additional thermal stress on the glass, which is not desirable, particularly in insulated glass units. Absorption of heat on the inner surface of an insulated unit traps the heat inside the room instead of rejecting it. Absorption of solar energy will also reduce the life expectancy of the film itself.

Achieve Improved Temperature Control While Fostering Natural Light

Recent technology allows us to provide window films, which are selectively reflective in that they reject more heat energy than visible light. Scotchtint type LE35AMARL, made by 3M with an “Amber” coating, reflects 60% of the heat passing through an insulated window while letting in much more light than comparable silver or neutral films. And their new “Prestige” technology, which reflects 96% of the infrared energy without any dyes, metals, or ceramics, reduces heat gain through single glass by almost 50% with hardly any effect on visible light. This film is perfect for retail display windows or any application in which the glass should not change in appearance.

Pittsburgh Window Film remains the most trusted name in window film in the Pittsburgh, PA, area since 1975. Our company was started by 3M to provide products from their Energy Control Products division. Over 40 years later, Pittsburgh Window Film is now an independent corporation and one of the longest-standing 3M Premier Elite Window Film Dealers. Our window films address a variety of concerns, including temperature control, fading, glare, privacy, security, and decorative aesthetics. Contact us for a free quote.

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