When windows aren’t cutting it, replacement is the obvious choice, especially when energy savings is a factor. But representatives for the window film industry say their products can be a cost- and energy-efficient alternative.

“Window films can offer as much as seven times the energy efficiency per dollar spent, compared to replacing a window,” says Darrell Smith, president of the International Window Film Association. Ranging from $3 to $11 per square foot, films offer a range of benefits at a reasonable price (see sidebar).

Window age and quality are good indicators of whether a film is the best choice. “It doesn’t make sense to take a structurally sound window that will last another 10 years and throw it out to invest the energy and materials to make and deliver a new window. That’s when window films make the most sense,” Smith says. “But if the window is damaged or you plan to replace in the next few years anyway, the payback isn’t the same.”

Smith also recommends paying close attention to film manufacturers’ compatibility charts. “Newer windows already have so many layers of coatings and are heat absorbent, so that using the wrong film on top of them could increase the heat load inside the glass,” he says. “That could lead to anything from a burst seal and interior fogging to thermal glass breakage.”

If films seem to be the best option, work with a trained window film dealer. These individuals have the skills necessary to properly cut the films and prep the glass for installation. A comprehensive dealer/installer locator is available on iwfa.com.

—Lauren Hunter, associate editor, REMODELING.