How Much Do Energy Efficient Windows Save

A work crew replaces the old windows at Nancy Munson's habitation in Downers Grove, Ill. Cheryl Corley/NPR hibernate caption

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Cheryl Corley/NPR

A piece of work crew replaces the old windows at Nancy Munson's home in Downers Grove, Sick.

Cheryl Corley/NPR

This story is part of a series called How Green Is Information technology? airing on All Things Considered. The series examines some of the things Americans are doing — and ownership — to assistance the surroundings and whether those steps really are as "green" as they seem.

Windows tin can provide not bad views and fresh air, simply they also can run up energy bills. That'southward why many people opt to supersede old drafty windows at domicile with new energy-efficient ones.

Those who choose this route tin at present go a federal revenue enhancement credit of upward to $i,500. Nancy Munson, a resident of Downers Grove, Ill., a suburb westward of Chicago, is i of many rushing to take advantage before the tax credit expires at the end of side by side year. Her 1950s-era two-bedroom cottage has its original widows, which have single-glass panes and metal frames.

Nancy Munson shows off one of the new vinyl replacement windows that she had installed last fall. Cheryl Corley/NPR hibernate explanation

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Cheryl Corley/NPR

Nancy Munson shows off one of the new vinyl replacement windows that she had installed last fall.

Cheryl Corley/NPR

"I was tired of my heating bills being so high in the winter because the windows were so drafty," Munson says. "I would put up plastic [over the windows], but the plastic would really accident off considering the current of air would go correct through the window. "

After she put energy-efficient vinyl-frame windows in the back of the house concluding fall, she says, her heating bills dropped past $25 to $l each month. Munson is spending $ix,000 for the front windows and hopes her free energy costs will drop further.

Windows Resources

— The Free energy Star Web site provides information about the federal tax credits for energy efficiency. Click on windows and doors for data specifically about windows.

— Efficient Windows Collaborative provides information on how to choose energy- efficient windows.

— The National Fenestration Rating Council is a non-profit organization that administers the rating and labeling system for the free energy operation of windows, doors and skylights.

Are New Windows The Best Approach?

Energy experts say there are less-expensive ways to reduce free energy costs. Brandon Thiele, the founder of Chicago Energy Consultants, says investing in windows is last on his listing in terms of building energy efficiency.

"You can't deny that a single-pane window is not going to be outperformed past a new double-pane or triple-pane window," Thiele says. "But the money that you would typically spend on that is typically better spent on sealing air leaks in the home and increasing insulation levels."

Thiele says homeowners can take some get-go steps that are far less expensive than new windows and offer more of an immediate payback. They include weather stripping or using plastic films to cover drafty windows, as well equally sealing up holes with cans of foam and caulk.

Consumers should also make sure attic spaces are well insulated and consider adding storm windows.

"More often than not, the big leaks y'all'll notice in the home that cause the biggest energy consumption are hidden in walls," Thiele says. He cites every bit an example an area of his own basement that he has yet to repair. Tucked near a back wall, air flows from a hole where the plumbing stack and vent for the furnace are located.

Nadav Malin, president of BuildingGreen.com, a visitor that specializes in ecology impacts on buildings, agrees that replacing windows might not be a first choice. But, he says, "at [a] certain point, if yous are going to make your house very energy efficient, you lot have to also bargain with the windows." He says consumers who are thinking almost replacing windows may be able to simply replace their window sashes (the framework that holds the panes of glass) to increase free energy efficiency.

Window Frames' Environmental Impacts

Materials used to construct window frames do take an touch on on the environs, Malin says. He was part of a chore force sponsored past the U.S. Green Building Council that studied the life cycle of the three most mutual window types: wood, vinyl and aluminum.

Forest windows enhance concerns virtually woods direction because trees have to be cut downward to make them. Plus, the frames require periodic painting and maintenance, Malin notes. Aluminum windows are energy-intensive to manufacture. They conduct heat readily simply are easy to recycle.

Some environmental groups argue that vinyl is likewise toxic to be considered green. "Vinyl is very stable, and in that location'southward really non whatsoever human health adventure to the homeowner," Malin says. "Information technology really has to do with some of the chemicals that are fabricated in the process of making vinyl and concern most its disposal at the end of its apply."

He adds, though, that the ecology impact of all of the window frames, including fiberglass and composites, is secondary to the thermal performance of the entire window. He says the main concern should be how constructive the window is at keeping heat on the side where it's wanted.

Window Ratings

Consumers who plan to replace windows should keep in mind the ratings that measure a window's energy efficiency. To help prevent "green fatigue," there are a number of Spider web sites that help decipher the regulations, including the federal government's Energy Star site.

The 2 most important factors to consider are the U-factor, which measures the rate of rut loss for an entire window, and the Solar Heat Gain Coefficient, or SHGC, which measures how effectively the window blocks rut coming from the sun.

In both instances, the lower the rating the better. Windows must have a U-gene and a SHGC of 0.3 or lower to receive the federal tax credit.

"I expect to get the $ane,500 back," says Munson, the suburban Chicago homeowner. The energy ratings for her new windows are lower than 0.3. And then, in addition to hoping for a cozy home during the winter, Munson says she hopes her new windows will increase the value of her domicile.