We’re not going to sugarcoat it. The best energy efficient windows are more expensive than regular windows. But that extra upfront cost is more than worth it because the windows will save you money and keep your home more comfortable in the long run.
According to the U.S. Department of Energy, non-energy efficient windows can account for as much as 25% of your energy bill by leaking heat in the winter or cool air in the summer. So, think about what could happen if you installed energy-saving windows that prevent that leakage.
The money you save from the best insulating windows will add up over time so that they’ll likely pay for themselves within ten years!
The concept of energy efficiency may sound a little abstract and technical, but the good news is it’s not that complicated. Identifying the best energy efficient windows is as simple as making sure the windows you choose have all these features:
- Double-pane glass
- Argon gas between the panes
- High-grade Low-E coating
- Energy Star and NFRC labels
- Low U-factor and solar heat gain coefficient
- Insulated vinyl window frames
- The same energy efficiency for all your windows
- Expert installation
We’ll take a closer look at why each of these features is important below.
1. Double-Pane Glass Provides an Extra Layer of Protection
They say two heads are better than one. The same goes for the glass in your windows. A single pane of glass doesn’t provide much of a barrier against the elements. But two panes with a buffer space between them are much more effective at stopping outside air from getting in and energy from leaving your home.
But while two panes are better than one, three panes aren’t better than two. Triple-pane windows add a third pane to the mix to provide even more insulation. But we don’t feel this third pane provides enough extra protection to justify the additional cost. Besides, the third pane can also reduce the visibility and light transmittance of the window.
Therefore, two panes of glass should be plenty. Not only can double-pane windows help with temperature insulation, but they are also effective at soundproofing. So, if you live in a noisy area, these windows can be twice as nice.
2. Argon Gas Improves a Window’s Insulation
As we mentioned above, all double-pane windows have a buffer space between the two panes of glass. In the best energy efficient windows, this space contains argon gas. This colorless and odorless inert gas does a fantastic job of keeping heat from escaping through the window.
What makes argon gas so effective at preventing heat transfer is it weighs more than air. So, when hot air gets through either of the panes of glass in the window, the argon gas stops it in its tracks and pushes it back where it came from. In this way, the gas deflects the sun’s heat in the summer and keeps in the heat from your furnace in the winter.
Some window companies out there may try to convince you that you need a heavier gas than argon to insulate your windows more effectively. Don’t fall for this ploy to get you to spend more money. Argon gas is more than capable of providing the insulation you need for your home.
3. High-Grade, Low-E Coating Protects from the Sun
The other feature the best energy efficient windows have is high-grade, low-emissivity (or Low-E) coatings. Low-E coatings are transparent films made of metal oxides that reflect heat off the glass but let natural light pass through.
The effectiveness of Low-E coatings varies depending on the types of metal oxides they’re made of. The best Low-E coatings are made of silver and have at least three layers of protection. According to Vitro Architectural Glass, triple-silver coatings allow as much as 70% of the sun’s natural light into a building while blocking 75% of its harmful energy.
4. Energy Star and NFRC Labels Indicate Trustworthiness
One of the easiest signs of quality to look for is Energy Star and NFRC labels. If a window has these stamps of approval, it means it’s passed the strictest tests for energy efficiency in the industry.
The Energy Star label signifies that the U.S. Environmental Protection Agency has inspected the window and found that it meets or exceeds energy efficiency standards in your state. So, Energy Star-certified windows come with proven energy savings.
The National Fenestration Rating Council (NFRC) is a nonprofit organization that also inspects and certifies windows. The difference between its certification and Energy Star is that it tests the whole window’s performance, while Energy Star only certifies the glass. So, NFRC certification is also essential when looking for the most energy efficient windows.
5. The Lower the U-Factor and SHGC, the Better
There are also a couple of numbers you can pay attention to when gauging how energy efficient a window is: the U-factor and the Solar Heat Gain Coefficient (SHGC).
A window’s U-factor is the rate at which it allows heat to leave a home. A typical U-factor for a window is somewhere between 0.20 and 1.20. The lower the number is, the more energy efficient a window is.
You also want to see a low number for the SHGC. This number measures how much solar heat a window lets enter a home. The total for a window will be somewhere between 0 and 1, and the closer to 0 it is, the better.
NFRC-certified windows will have both the U-factor and the SHGC listed on their labels.
6. Choose an Insulated Vinyl Frame Over Other Materials
The frame material can make or break the energy efficiency of a window since certain materials provide better insulation than others. On the worse end of the spectrum are metal and aluminum frames, which conduct hot and cool air into the home rather than keeping it out. Conversely, the best materials for window insulation are vinyl and wood.
Vinyl frames are great for insulation because they consist of interlocking chambers, which manufacturers can fill with insulation material. However, not all windows contain insulation, so you’ll want to make sure your windows do when purchasing them.
Wood window frames also provide a good amount of insulation. However, they don’t provide as much energy efficiency as insulated vinyl frames. Wood also requires more maintenance than vinyl since it decays more quickly over time. For this reason, we consider vinyl the ideal material for the best insulating windows.
7. Make Sure All Windows are Energy Efficient
Customers will sometimes ask us if we recommend only installing energy efficient windows in the areas of their home that are most vulnerable to the sun. This way, they can have regular windows on the rest of their homes to save money. We always tell them it’s a bad idea.
While having a mix of energy efficient and regular windows will save you money, it won’t give you the long-term results you’re looking for. After all, your home will still be vulnerable to energy leaking out of those regular windows.
A helpful illustration for this is to picture a Styrofoam cup with ten holes poked in it. If you plug three of those holes and pour water in, will the cup hold water?
In the same way, a home with ten windows and only three that are energy efficient won’t keep your energy bills from rising. Therefore, we recommend installing energy-saving windows throughout your home.
8. Proper Installation Makes All the Difference
It won’t matter how high quality your insulated windows are if they’re not installed properly. Each window needs to be cleanly mounted into the frame with low expansion insulation applied around it. Otherwise, energy could leak out around the outside of the window.
To ensure this doesn’t happen, we recommend hiring an experienced professional to install your windows for you. This way, you’ll get the most out of your long-term investment in energy efficiency.
Get the Best Energy Efficient Windows Installed in Chicago
When it comes to the best energy efficient windows, you get what you pay for. Clearly, this extra investment is worth it for the money you save and the comfort you gain in the long run. And finding these high-efficiency windows is as easy as looking for a few specific features.
Do you need more assistance finding the best energy efficient windows for your home? At Your Window Solutions, we put your needs first to give you the beautiful, high-performance windows you need. We provide window replacement services in Lake in the Hills, McHenry County and the Greater Chicago Region.
Please call 833-367-9687 or fill out our contact form to request a free consultation. We look forward to helping you!
Editor’s Note: This blog was originally published in June 2022 and updated in December 2022.