What is Low-E glass?

Low-E stands for low emissivity, or low thermal emissivity and is a surface treatment on the glass that lowers the levels of radiant thermal energy.

Simply taken from Wikipedia, this coating helps “keep heat on the side of the glass where it originated, while letting visible light pass. This results in glazing with better control of energy – heat originating from indoors in winter remains inside (the warm side), while heat during summer does not emit from the exterior, keeping it cooler inside.”

Pella offers three different levels of low-E glass outlined below. Additional information can be found here.

  1. Natural Sun Low-E: Intended for very cold climates, this provides some infrared light (warm light) through, but still blocks 69% of the UV light.
  2. Advanced Low-E: Recommended for most climates and blocks more infrared light for warmer climates, and blocks 84% of UV light. This is the grade of Low-E that is quoted STANDARD with ThermaScreen quotes.
  3. SundDefence Low-E: Most effective low-E and intended for very bright and hot desert climates. Blocks the most infrared light, and 94% of UV light.

Additional information on how low-E affects temperatures here is a short video from Pella where they show the differences between normal glass and low-E using a thermal camera.

Please feel free to contact us for more information.