Triple-paned windows can save you more energy during the summer than the winter, but dont be looking for a quick monetary payback on your investment.
Northwest researchers found it can take decades before savings from these highly insulated windows pay you back.
Researchers are using two identical homes to test some of the latest advances in energy efficient appliances, heating and cooling systems, and most recently, windows.
One home was retrofitted with triple-paned, extra-insulated windows. The other has typical aluminum-framed windows found in most Northwestern homes.
Researchers at Pacific Northwest National Laboratory found the energy-efficient windows cut your homes energy use by about 12.2 percent throughout the year.
The labs Graham Parker said the windows are expensive and could take 23 to 55 years to start paying you back.
Windows are not one of the more cost-effective retrofits that you can do to a building, unless, of course, your windows are broken, or theyre letting a lot of air leakage through around the window frame, Parker said.
The researchers found that the windows saved more energy in the summer than in the winter, 18.4 percent and 11.6 percent, respectively.
We were a little bit surprised, Parker said. I think the biggest reason is the highly insulating windows have what we call low emissivity coating, or low-e coating. That tends to block a lot of the radiation coming from the sun in the summertime.
Parker said the triple-paned windows can make homes more comfortable by reducing that drafty, cold feeling thats common near older windows.
They can also prevent condensation, which would in turn reduce mold.
Thats really an issue from a health perspective, Parker said. Moisture and condensate creates mold; mold growth creates spores, which can create health problems in a lot of homes.
Parker said the most cost-efficient time to install the triple-paned windows is when youre building a new home.