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Advances in film and thin-glass technology have made lightweight quad-pane windows a cost-effective alternative to typical double-pane windows.
Researchers from the National Renewable Energy Laboratory found 24% average HVAC savings compared to high-performing double-pane windows. View full-size infographic. [PDF - 282 KB]
Reference above to any specific commercial product, process or service does not constitute or imply its endorsement, recommendation or favoring by the United States Government or any agency thereof.