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U.S. Department of Energy
Office of Scientific and Technical Information

Window annual energy rating systems: What they tell us about residential window design and selection

Conference ·
OSTI ID:687646
; ;  [1]
  1. Enermodal Engineering Ltd., Kitchener, Ontario (Canada)
Residential window annual energy rating systems have been developed in Canada and the US. These systems combine window properties of solar heat gain coefficient, U-factor, and air-infiltration into a single number representative of the energy performance for each of the heating season and the cooling season. These systems provide a simple means for designers to select the best energy performing window for low-rise residential buildings over the heating and cooling seasons. The two systems, which rank windows in the same order, give different information on optimum window design and selection than just a simple U-factor comparison. These systems show the importance of a high window SHGC in cold climates and a low SHGC in hot climates. The impact of window air infiltration is surprisingly small relative to the solar heat gain and heat conduction losses.
OSTI ID:
687646
Report Number(s):
CONF-980650--
Country of Publication:
United States
Language:
English