R-Value equals resistance to heat flow. The higher the number the better.
Well insulated walls have an R-Value of 13, why should settle to have your windows any less.
Mainly used in storm windows.
R-.8
Double Pane Insulated Glass:
Ordinary windows.
R-1.8
Double Insulated with Low E:
Reflects Heat from it's source.
Blocks out 60% UV Rays.
Increases R-Value.
R-2.5
New Three Dimensional Low E :
Two coat Low E.
Krypton Gas
Warmer Glass Temp.
Reflects Heat from it's source.
Blocks out 80% UV Rays.
Increased R-Value.
R-5
An Excellent $Value$
Triple Two Coat Low E:
Glass Temp. Warmer.
Reflects Heat from it's source
Blocks out 80% UV-Rays.
R-Value increases.
R-7
