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Title: Demonstration of the Performance of Highly Insulating (R-5) Windows in a Matched Pair of Homes

Improving the insulation and solar heat gain characteristics of a home’s windows has the potential to significantly improve the home’s overall thermal performance by reducing heat loss (in the winter), and cooling loss and solar heat gain (in the summer) through the windows. A high-quality installation will also minimize or reduce air leakage through the building envelope, decreasing infiltration and thus contributing to reduced heat transmission through building envelope. These improvements all contribute to decreasing overall annual home energy use. In addition to improvements in energy efficiency, highly insulating windows can have important impacts on occupant comfort by minimizing or eliminating the cold draft many homeowners experience at or near window surfaces that are at a noticeably cooler than the room air temperature. Energy efficiency measures, such as highly insulating windows, also have the potential to decrease peak energy use in a home, which can lead to measurable peak load decreases for a utility service territory if implemented on a large scale. High-performance windows now feature triple-pane glass, double low-e coatings, and vinyl insulated frames to achieve U-factors as low as 0.2 , as compared to double-pane clear glass windows with a U-factor of 0.67, which are common in existingmore » homes across the United States. The highly insulating windows (as they will be referred to in this document) are now available from several manufacturers and show promise to yield considerable energy savings and thermal comfort improvements in homes.« less
Publication Date:
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Resource Type:
Resource Relation:
Conference: Thermal Performance of the Exterior Envelopes of Whole Buildings XII, December 1-5, 2013, Clearwater, Florida
ASHRAE, Atlanta, GA, United States(US).
Research Org:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org:
Country of Publication:
United States
building energy efficiency; residential retrofit; high performance windows; Low-E; R-5; highly insulating