Caulking seals air leaks around existing windows as well as new windows. (Photo courtesy of rareformproperties.com)
Homeowners often fret about their older windows, perhaps even original to the house — maybe they let in cold drafts during the winter, or contribute to overheating in the summer. People like the look of the older windows, and replacing them with new ones is expensive. In last month’s column, we talked about replacing windows, but doing so is costly, and it could take 20 years of energy savings to recover the investment.
You can, however, make significant improvements to your existing windows without investing a large amount of money or time.
Energy loss and drafts often occur in the cracks between the components of the window. Weatherstripping can be used for areas where a window’s movable parts meet the window frame, where drafts often sneak through. Retailers offer a variety of low-cost, easy-to-apply weatherstripping for different types of windows, and they can pay for themselves in energy savings in as little as one year.
The seam between the window frame and the wall is another common source of air leakage. Fill gaps less than ¼ inch wide with caulk; for anything larger, use expanding foam and paint over it.
Of course, loose, cracked, or even missing glass panes can mean significant heat losses. If you’re handy, it’s possible to re-glaze a window yourself, or there may be a local shop in your area that will do it.
Installing exterior or interior storm windows, which you can order to fit the exact size of your window opening, can sometimes produce as much savings as a full replacement, cutting heating costs by as much as 7 to 12 percent.
There are many types of other window coverings, including interior roller shades, cellular shades, or draperies, that can cut heating or cooling expenses by 10 to 16 percent. Draperies are usually less efficient, so make sure they overlap in the middle, are as tight to the window and wall as possible, and run all the way to the floor.
The best way to reduce overheating in the summer is to keep the sun’s rays from reaching the window — awnings or overhangs, or window films that adhere to the window surface, can protect the interior from unwanted summer sun.
Another low-cost measure for these areas that can produce as much savings as storm windows is to fashion a plastic weather barrier that adheres to the frame. Building supply retailers sell a clear plastic and framing material that can be shrunk into place by using a hair dryer.
To learn more about improving the efficiency of older windows, visit www.energystar.gov or www.energy.gov. You may also want to check with your local electric co-op, as many offer incentives and are knowledgeable about local suppliers and contractors.
Pat Keegan and Brad Thiessen write for Collaborative Efficiency, an energy communications company.
