Feb 12 , 2019
Keep out those winter winds by sealing up your drafty windows.
The best way to winterize your windows is to add a sealed layer of plastic or glass over the window. And the cheapest, easiest way to do this is by installing an interior window insulation kit. Duck brand Shrink Film Window Insulation Kit and 3M Window Insulator Kit are two readily available options. Winterizing windows should always start with interior and exterior caulking and weatherstrip repairs.
But these steps don’t always stop all of the the leaks. Covering the entire window with a layer of heat-shrink plastic from one of these kits has two advantages. First, it completely seals the window, eliminating any air infiltration. And second, adding a layer of plastic creates an insulating layer of air that boosts the windows R-value.
The kits include double-sided tape that you apply to the perimeter of your window, usually on the window trim. Then you cut a slightly oversized piece of the plastic film and carefully adhere it to the tape. Complete the project by applying heat from a hair dryer to shrink the plastic film for a wrinkle-free installation. Finish up by trimming the excess plastic for a neat look.
The cost to cover an average 3-foot x 5-foot window is between $1.50 and $3.00, depending on which kit you choose. While energy savings vary greatly depending on how leaky your old windows are and your energy costs, you’ll certainly save enough by winterizing your windows with heat-shrink plastic to repay the cost, and in most cases you’ll save even more. But the real benefit may be in the added comfort this winterizing method brings by eliminating cold drafts.
There are a few downsides to this winterizing method, however. First, removing the sticky tape at the end of the season can cause damage to the paint or varnish on your trim. Also, the fact that this is a disposable solution makes it less environmentally friendly than a more permanent fix.
For a longer lasting solution, interior storm windows are a good alternative to heat-shrink plastic. Because they cover the entire window from the interior side, they have the same advantages of heat-shrink plastic, but will last decades. Interior windows are custom made to fit your window openings. Some fit into tracks, while others have compressible weatherstrip perimeters that allow a press-in installation.
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