Efficient Windows Collaborative (EWC) members have made a commitment to manufacture and promote energy-efficient windows. This site provides unbiased information on the benefits of energy-efficient windows, descriptions of how they work, and recommendations for their selection and use. Take a look to learn more!


  • Steve Selkowitz, head of the Building Technologies Department at Lawrence Berkeley National Laboratory speaks on"Energy-Saving Windows A Legacy Of '70s Oil Crisis" on National Public Radio (NPR). Listen now»
  • The fall edition of EWC's newsletter, Word on Windows is now available. View now»
  • A multiple benefits fact sheet is now available which combines several measurable attributes (annual energy cost, peak demand, winter and summer thermal comfort, and condensation) to assist in the window selection process. View now»
  • The third edition of Residential Windows: A Guide to New Technologies and Energy Performance is now available and provides updated and expanded information on window properties and technologies, as well as new sections on such key topics as window installation, energy efficiency, and building codes. More information»
  • The EWC has developed toolkits for manufacturers, designers, and builders who seek to provide their customers with low energy costs and comfort through efficient windows. See toolkits»
  • Let utilities help you finance more energy-efficient windows for your home. Download an overview of Utility Programs that Offer Incentives and Rebates for Energy-Efficient Windows»
  • Decision makers in the low-income housing sector can find options for financing energy efficiency measures through this web portal presented by the EWC. Download "Improving Energy Performance in Low-Income Housing"

Efficient Windows Collaborative

This site is sponsored by the EWC with support from the U.S. Department of Energy's Windows and Glazings Program
and the participation of industry members.

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