Thermal Performance Data

Earthwise/ American Window Thermal Performance

ProductTotal Unit
U- Factor
Total Unit
SHGC
Visible Light TransmittanceUV
Block
The Horizon, Yellowstone or PrimeLok Single HungClear: 0.49
Low E and Air: 0.34
Clear: 0.59
Low E and Air: 0.31
Clear: 82%
Low E and Air: 57%
Clear: 42%
Low E and Air: 84%
The Solaris, Yosemite, or PrimeLok Double HungClear: 0.49
Low E and Air: 0.35
Clear: 0.58
Low E and Air: 0.30
Clear: 82%
Low E and Air: 54%
Clear: 42%
Low E and Air: 84%
The Horizon, The Solaris, Yellowstone, Yosemite or PrimeLok Single SliderClear: 0.49
Low E and Air: 0.34
Clear: 0.55
Low E and Air: 0.31
Clear: 82%
Low E and Air: 56%
Clear: 42%
Low E and Air: 84%
The Horizon, The Solaris, Yellowstone, Yosemite or PrimeLok Picture WindowClear: 0.49
Low E and Air: 0.33
Clear: 0.62
Low E and Air: 0.32
Clear: 82%
Low E and Air: 59%
Clear: 42%
Low E and Air: 84%
The Eclipse, Grand Mesa or TruLokClear: 0.49
Low E and Air: 0.35
Clear: 0.58
Low E and Air: 0.30
Clear: 82%
Low E and Air: 54%
Clear: 42%
Low E and Air: 84%
The Solstice, Grand Teton or GrandLokClear: 0.49
Low E and Air: 0.35
Clear: 0.58
Low E and Air: 0.30
Clear: 82%
Low E and Air: 54%
Clear: 42%
Low E and Air: 84%
The Aurora or Cascades Casement / AwningClear: 0.45
Low E and Air: 0.31
Clear: 0.56
Low E and Air: 0.31
Clear: 82%
Low E and Air: 72%
Clear: 42%
Low E and Air: 84%

Terminology

Emissivity is a measure of a surface’s ability to emit long-wave infrared radiation or room temperature radiant heat energy. Emissivity varies from 0 (no emitted infrared) to 1 (100% emitted infrared). The lower the emissivity, the lower the resultant U-Value.

U-Value is the amount of heat transmitted by the window. The lower the number, the more efficient the window is in reducing winter heat loads and costs. Expressed in Btu/hr.ft2.F.

R-Value designates a window’s resistance to heat flow. This number is the inverse of the U-Value: the higher the number, the more efficient the window in reducing winter heating costs. Expressed in hr.ft2.F/Btu.

Solar Heat Gain Coefficent is the fraction of incident solar radiation entering a home through the windows. The lower the number, the better the window is at preventing solar gain – critical to reducing summer cooling costs.

Ready to get started with American Window?