Keeping your home insulated and energy efficient is an important way to save money on energy bills. In cold climates, windows can be allowing precious heat to escape, and in hot climates, cool air garnered from a colder night or AC could be leaking out. Getting energy-efficient windows has also been shown to reduce energy bills. The Department of Energy states that the loss or gaining of heat through your windows is 25-30% of residential energy use. By improving the efficiency of your windows, you can give yourself a more comfortable home and lower your greenhouse gas emissions.
Improving Your Current Windows
There are some things you can do to improve the efficiency of your current windows, even without fully replacing them:
- You can check for air leaks in your windows, looking for any visible damage or separation where the window connects to the frame and the frame connects to the wall.
- Particularly if you have wood window frames, it may be time to repair your window frames. Because they are more prone to deterioration over time, it could be best to replace the frame.
- Add window caulking and weather strips to the side and joints of your windows to limit drafts and improve insulation.
- Put in energy-efficient window coverings such as blinds, shades, and curtains.
- Install low-emissivity storm windows or panels as extra panes to your windows, ensuring better insulation.
- You can add solar control window film to block solar heat and UV rays during warm weather.
- By installing awnings or overhangs outside your windows, you can keep them in the shade and reduce the warming effects and glare of the sun.
However, there is a certain point when these changes become more time-consuming than getting replacement windows with many of these features already included. While newer windows only need some of the above fixes to become more efficient, older windows need a lot of work. Because older windows were constructed with less insulation and time has worn on them, replacing them would likely be more efficient. New, energy-efficient windows could be your answer to saving money on your energy bill and reducing your carbon output.
What Makes a Window Energy Efficient?
Windows that are considered energy saving or energy efficient are windows that limit the airflow in and out of your home. By increasing the insulation of your house, they keep more even temperatures and prevent the loss of heating or cooling, saving you energy and money. The materials and construction of these windows are such that cool air is kept in the house during hot weather, and warm air is kept inside during cold weather. Energy-efficient windows are functional in any climate.
Double or Triple Pane Glass
Windows with two or three layers of glass create better insulation and more sufficiently block UV rays. This mostly affects the heat loss/gain by trapping air in the insulated areas between the glass panes.
Spacer systems are part of the double or triple pane windows, which keep the panes and layers of glass the correct distance apart. This helps prevent moisture or air leaks. Because of the direct connection they provide between the outside and inside, window spacers have to provide a tight seal. This helps them provide protection for your home and ensure the special gases that are between the layers of glass stay in place. Spacers also allow for heat expansion and pressure changes that your windows endure throughout the seasons.
Low-Emissivity Glass Coating
Low-emissivity, or low-e, glass coatings are made with a nearly invisible, incredibly thin layer of insulating metal or metal oxide, which controls the heat transfer through the glass. While it can make windows more expensive, it’s also incredibly efficient at reducing costs, lowering energy loss by 30-50%. The coating can handle both light transmission and solar heat, and you can select different types of low-emissivity coating to best match your climate. Low-e coatings can be designed to allow different levels of solar gain, as well as different amounts of light.
To further lower the heat transfer between double and triple pane glass layers, the insulated space is filled with argon or krypton gas. The two gases have different applications — argon is better for the standard half inch, and krypton is better for thinner gaps. However, both gases are clear, non-toxic, and odorless. Because of the denseness of these inert gasses, they slow down and even stop the heat from passing through the panes and into your home.
What to Look for in Different Window Features
Other components of an energy-efficient window are a bit more functionally straightforward — it refers to the frame and how the window opens. These are still important features to consider, however, as they can also impact energy efficiency, even if they’re not new features.
The way the window opens has a big effect on insulation and air leakage. Windows that slide generally have higher air leak rates than windows with hinged or projected operating styles. This knowledge can help you choose which windows are best for your energy use.
The frame is also important to your energy efficiency. While metal or aluminum frames are light and easy to maintain, they conduct heat easily and are very poor insulators. This can be improved with plastic strips, but they are still not the most energy saving. Wood frames are better at insulating, but they require a lot of upkeep and attention. Frames that are made of composite material, fiberglass, or vinyl are often better insulated and have fewer moisture issues than wood frames.
Savings With New Windows
The exact cost of an energy-efficient window installation will depend on which of these styles and construction of window you chose, but those changes would make drastic differences in your energy savings. To better understand the kinds of savings you could get through energy-efficient windows, it’s recommended that you have an energy audit. That way, you can be more certain of the savings you can gain and know if energy-saving windows are the right choice for your home.