This Window insulation guide offers a range of ways to reduce energy use by adding insulating materials to your windows. Windows that are not properly insulated are a leading source of heat loss in the winter and heat gain in summer, so doing what you can to insulate them will reduce your energy costs.
Reasons to Insulate Windows
In winter, heat created by your furnace, heat pump other heat source can escape through drafty windows and the glass itself. In summer, heat from outside, especially radiant heat from windows exposed to direct sunlight, will cause your home to warm up significantly. If you’re using air conditioning, it will work much harder when windows are poorly insulated.
Choosing Energy Efficient Windows
If you’re building a home or replacing windows, choose energy-efficient products. Most manufacturers make glass packages with low-e glass that slows the transfer of heat. Many feature two panes of glass with gas such as Argon between them that reduces heat loss or gain. Triple-pane glass is available too from most top manufactures. The additional pane of glass and the air gap between them creates a barrier to heat. If you want to find out more about energy efficient window prices then visit our very own Window Price Guide website.
You will also find window glass that is treated to reflect sunlight or tinted to impede the transfer of heat. Check with local window contractors for options.
In addition to glass, many manufacturers make insulated window frames that reduce heat loss and gain. They are available from top brands like Andersen, Pella and Marvin.
Window Insulation Film
Window kits are available from several manufacturers featuring clear plastic film that covers existing windows. The plastic affixes to the wall surrounding the window. It seals with tape. Some film types can be shrunk with heat to stretch tight to provide a clear view.
The purpose of the film is to produce an air gap between the window and the living space. The air gap acts as insulation with a value of roughly R-1 per inch. A four-inch air gap can be equal to roughly one inch of rigid foam insulation.
Window insulation film can be a DIY project, though insulation contractors install it as well. When considering a contractor for the work, get several written estimates to compare costs and find a company you believe will do a good job.
Window Insulation Costs
|Installation||Cost per Window||Average Cost per Project (Based on 15 Windows)|
|Install it Yourself||$2.00 to $3.00||$30.00 to $45.00|
|Hire a Contractor||$5.00 to $8.00||$75.00 to $120.00|
The cost of window insulation kits is $2 to $3 per full-size window if you plan to do it yourself. If hiring a contractor, expect to get estimates of $5 to $8 per window.
Additional Ways to Increase Window Efficiency
There are several things to consider doing in order to reduce heat loss or gain through windows. Start by making sure the frames are tight and well caulked. Add awnings to windows that receive a lot of direct sunlight. Reflective and/or insulated blinds, shades and curtains will also reduce the gain or loss of heat. Reflective window film can also be used, though it may result in a small loss of interior light and impaired visibility to the outside.