Hard Coated Low E Glass U Values
Hard Coat, Air, 3 chamber profile

1.90

Hard Coat, Air, 5 chamber profile

1.80

Soft Coated Low E Glass U Values
Radley Eclipse 3 chamber profile 1.73 standard
Radley Eclipse 3 chamber profile Argon gas 1.57 option
Radley Esthetique 5 chamber profile 1.63 standard
Radley Esthetique 5 chamber profile Argon gas 1.47 option

The top table is based on an average window size and design and the U values for that window fitted with Pilkington Low E by A N Other Windows. The lower table Radley standard Esthetique window would save 10% or more on your heating costs. Many windows, dependent on size and design, will show even greater savings. A computer generated report will be available for every purchase made.

 
The thermal performance of a building material is measured by its U-value. This measures the ability of an element to slow down the transmission of heat. The lower the U-value, the greater the thermal insulation achieved.