Replacement Windows Need Replacing Every 10 Years!

All my buyers want new windows but dollar for dollar, do they save enough energy to justify the cost?

Don't be seduced by the newspaper ads promising big energy savings for low priced replacement windows, warns writer Wayne Curtis in Preservation Magazine, the magazine of the National Trust for Historic Preservation.

"Replacement fireplaces and replacement walls would make more sense," Walter Sedovic, a New York architect who specializes in preservation, told Curtis in the January 2008 Green issue of Preservation. Replacement windows are "easy to construct, easy to transport and easy to sell," Sedovic says, "but they don't really make sense for the energy conscious."

Curtis went to the Whole Building Design Guide for the proof: Older single pane windows have an insulation factor of R1, the Guide says. Modern double glazed windows offer R3. "Taking a window from R1 to R3 will not provide sufficient energy savings to offset the cost of replacement windows and associated waste,"the Guide says. Restoring and maintaining old windows makes more sense, Curtis concludes.

We call them replacement windows because we keep replacing them! Sedovic credits his colleague John Seekircher with coining that phrase.

"...Only 10 to 12 percent of total air infiltration in a building is through the windows," Sedovic told Curtis. "The cold isn't being transferred through the glass. It is through the openings in and around the sash. The energy loss is mostly through the roof and through the sill," Sedovic explained. That is why he advises people to look to their fireplaces and walls for sources of energy loss. The high tech seals on modern windows eventually fail, Curtis writes. "You don't repair them. You replace them." There is a sad irony in the idea of replacing 100 year old windows with so-called "envionmentally responsible" windows that will be junked and replaced every decade or two, Curtis concludes.

We all want an easy, affordable fix, so I am sorry to learn that "replacement windows" are not the cure-all they are advertised to be.