Window Retrofits, Not Replacements, Are Cost-Effective

A new study shows that retrofits to old windows can provide nearly the same savings with far lower initial costs.

“Saving Windows, Saving Money: Evaluating the Energy Performance of Window Retrofit and Replacement,” from Preservation Green Lab and other groups, compared retrofit options to replacement windows and typical existing single-pane windows in five cities in hot, cold, and moderate climates across the U.S. Retrofit options included weatherstripping, interior films, interior panels, insulated cellular shades, exterior storm windows, and combinations of those options. In all five cities, the combination of storm windows with insulated shades yielded approximately 90 percent of the energy savings of replacement windows at about half the cost. (For more on choosing the right window attachment, see “Making Windows Work Better,” EBN June 2011.)