U-Value and the Energy Star® Program
A new government program funded by the Department of Energy and presided over by the National Fenestration Rating Council, known as Energy Star, measures a windows value by its conductivity. In the northern one-third of the United States, Energy Star mandates that a window must have a .35 or lower U-value in order to be compliant.

All our windows meet and exceed that standard in testing. In fact, initial tests showed our windows meet the .35 Energy Star U-Value goal with just Low 'E' glass, whereas most windows require the addition of Argon gas to achieve a .35 rating. With Argon, our windows tested at .32 U-Value. To see the test data click here.

Air Infiltration
The American Architectural Manufacturer's Association says that if a window leaks .30 cubic meters of air per lineal foot of crack or less in a 15 mph wind test chamber, that's a good window. All our windows meet and exceed that standard in supplier generated testing. Test results range from 10-90% better than the limit, depending on the style, type and size of the window tested.

Water and structural load testing are both available. If you desire, please ask your sales representative and they will obtain that information for you.