06/11/13

New Efficient Windows Collaborative Website Offers Expanded, Updated Features

Last year, over 200,000 people turned to the Efficient Windows Collaborative (EWC) website for accurate, unbiased information on window energy performance. This spring, the Collaborative released a new version of the website, which includes updated  and detailed window selection tools.

Importance of Efficient Windows

Windows play an important role in a home’s energy performance. In areas that require primarily heating, efficient windows can prevent significant heat loss, and in areas that require primarily cooling, efficient windows can prevent substantial heat gain. Not only do more energy-efficient windows save money on heating and cooling, but in doing so they can also allow for a much smaller HVAC system, improve home comfort (primarily through reducing drafts), and reduce condensation. The Efficient Windows Collaborative has more detailed information on the benefits of efficient windows.

Unlike choosing many other high efficiency products or components, the energy efficiency of a window will depend on the home’s location and the orientation of the window on the house, among other factors. Importantly, different energy performance features are desirable in different climates—the window that provides the best performance in one location and orientation, may not in a different location or orientation.  

Updated Window Selection Tool

The EWC Window Selection Tool for new construction and replacement windows takes user input on the home’s location, orientation, and window shading to provide information on the energy performance, comfort, and condensation provided by various window types. The tool provides estimates of annual energy costs associated with the window types, broken apart by heating and cooling. The cost information also helps consumers request and evaluate estimates by quantifying the impact different choices will have on their home’s operating costs.

The new release of the tool updated the information on window energy performance with additional window options and new performance data, and expanded the information to include analysis of each window type’s comfort and condensation. The EWC relied on Lawrence Berkeley National Laboratory’s RESFEN 6 for the updated data. The tool also now considers window area, shading, and orientation, which increases the accuracy of the recommendations and savings estimates.

New Design Guidance

The EWC also provides guidance to homeowners in designing a home with energy-efficient windows and skylights. The new guidance is broken into three climates (cold, mixed, and hot) and explains the various design factors, such as window area, orientation, and shading will impact the performance of the home’s windows.

In addition to design guidance, the EWC has also updated information on various window technologies such as the gas fills, frame types, and operator types.

Whether you are replacing your windows or building a new home, the Efficient Windows Collaborative provides tools and information on selecting windows that provide lower energy costs and greater comfort. With updated backend analysis and design guidance, new options in the Window Selection Tool, among other features, the new release can help you more easily and accurately choose energy-efficient windows and skylights.

The Efficient Windows Collaborative

The EWC works to advance the selection of high efficiency windows and skylights as a coalition of window, skylight, and component manufacturers in addition to industry stakeholders and other affiliates. Members include some of the largest manufacturers in the industry such as Andersen Windows & Doors, Pella Corporation, Ply Gem, and Marvin Windows and Doors, among others. The Collaborative is jointly administered by the Alliance to Save Energy and the University of Minnesota Center for Sustainable Building Research.

The EWC plays an important role in helping consumers understand window energy performance features and metrics by translating product data into understandable, actionable and scientifically grounded window performance information and recommendations.