Customer Care: Frequently Asked Questions
What would you determine as the most important issue when dealing with energy performance?
Today's windows are tested in almost every conceivable condition and in most cases quality windows perform almost identically. You will hear the term R and U values used in almost every window discussion, however; most quality windows are so close in performance as far as R and U values are concerned, it has almost become a mute point. So for that reason I would say that D.P. rating (Design Pressure) is the single most important factor. D.P. rating measures a windows ability to withstand air and water infiltration under pressure. The higher the D.P. rating the better the window.
