Hi-R Low-E Window Retrofit System

High performance or “Hi-R” windows use advanced technology to deliver up to a seven-fold improvement in a window’s thermal performance. At a GSA test bed location in Provo, Utah, Hi-R panel retrofits, which are installed on top of existing windows, reduced heating loads by up to 41%. View full-size infographic. [PDF - 242 KB]

GPG Findings 007, December 2013, Highly Insulating Window Panel Retrofit. Opportunity: How much energy is lost through inefficient windows in commercial buildings? 23% energy used to heat and cool buildings is lost through inefficient windows. Technology: How do Hi-R Window Panel Retrofits save energy? Improve thermal performance with low-e window panels. Pre-manufactured like storm windows; simplifying installation. Measurement and Verification: Where did M and V occur? Lawrence Berkeley National Laboratory assessed the impact of Hi-R panel retrofits on heat-load reduction and employee comfort in Provo, Utah federal office building. Results: How did Hi-R Window Panel Retrofits perform in M and V? 41% heating savings in winter. Estimated savings for entire building heating and cooling: 11%. Quick installation. Improved visual and thermal comfort. Less than 9 years payback for triple-pane; double pane will be shorter. Deployment: Where does M and V recommend deploying Hi-R Window Panel Retrofits? Buildings in cold climates with single-pane windows. Double-pane retrofits recommended, as triple-pane offers diminishing returns. Site-specific evaluation is critical. [PDF - 242 KB]


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Last Reviewed: 2022-09-01