I am concerned that in the IECC 2012 codes, the maximum U-values in northern U.S. climates have been lowered to 0.32, making the use of high solar heat gain coefficient (SHGC) windows more difficult, since high SHGC windows have increased U-values due to slightly increased radiative heat transfer in the near infrared. In sunny northern and central U.S. climates that are predominately heating, and where houses are not shaded, my calculations show an advantage of going with higher SHGC's, which would also increase the U-values.
I am looking for a list of window companies that still provide high SHGC, low-e windows, that I can include in a report on the subject. My current list includes the following (probably compiled from discussions in this forum): Pella (Designer Series only), Thermotech, Inline, Fibertec, Serious, Milgard, Accurate Dorwin, Gienow, and Marvin. This list does not need to be all inclusion, since there are a zillion window companies, but I would like to include some of the major players. Thanks for the help. |