Design Options for Low-Conductivity Window Frames

The window industry's commercialization of low-emissivity coatings and low-conductivity gas-filling over the past few years has helped to drastically reduce heat transfer rates through the glazed areas of windows. However, few changes have taken place in the design and construction of window frames and edges, leaving these elements to account for most of the heat transfer through today's state-of-the-art windows. This paper presents design and material requirements for the manufacture of low conductivity window frames obtained through the use of finite element computer modeling. Such frames will compliment and not degrade today's most-energy-efficient insulated glass units.