How Do Energy-Efficient Windows Work?

Jun 17, 2019

If you have old-style, single-pane windows in your home, the chances are pretty good that you’re spending more money to heat and cool your home than you would if you upgraded to modern energy-efficient windows. In fact, the opportunity to enjoy beautiful new windows and lower utility bills is the primary reason that many homeowners seek energy-efficient windows. However, there’s also the satisfaction of knowing that you’re doing your part to conserve precious natural resources and preserve a healthy environment. To make it easy for homeowners to identify energy-efficient windows, the U.S. government and the window industry teamed up to create the ENERGY STAR® certification program. Replacement windows that meet the standards set by this program qualify as ENERGY STAR® windows, and that’s a handy way for homeowners to evaluate whether they’re truly investing in a home upgrade that will help them reduce their energy consumption.

Understanding the Components of Energy-Efficient Windows

Although looking for the ENERGY STAR® label is one way to identify energy-efficient windows, if you’re interested in maximizing the thermal performance of replacement windows, it can be helpful to know what features to look for. At Johnson County Siding & Window Co., we’ve been using our industry expertise to help homeowners in the Kansas City metro area choose high-performing energy-efficient windows for many years. A few of the features we typically point out are:

Multi-Pane Construction

Energy-efficient windows typically have at least two glass panes with inert gas filling the space between them. This type of construction blocks heat transfer far better than a single-pane window can. Some windows are available with triple-pane glass, which will increase their energy efficiency even more.

Low-Emissivity Glass Coating

Commonly referred to as Low-E, this coating can block up to 90% of the sun’s rays from entering your home through your windows. The more layers of this coating there are, the more energy efficient your windows are likely to be.

Window Spacers

The most energy-efficient windows will have premium-grade spacers crafted from silicone foam or stainless steel. A window’s spacer system is important because it maintains the proper distance between panes and helps preserve the window seal, thus minimizing air infiltration.

Depending on the type of replacement windows you’re considering, you may find additional features aimed at enhancing energy efficiency, including triple weather stripping and foam insulation. If you’re on the hunt for energy-efficient windows for your home in the Kansas City metro area, Johnson County Siding & Window Co. stands ready to help. Contact us today, and we’ll be happy to tell you about the industry-leading energy-saving features of the replacement windows we install for homeowners throughout this area.


If you know you want to get your home exterior project done, but are feeling stress about paying for it all at once, we can help.

Our financing partner, GreenSky, has sensible payment plans that work for homeowners who prefer to pay in installments. You can also ask your JoCo Siding & Window Co. sales representative about the details!

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Our Customers LOVE The Results

Johnson County Siding & Window Co.
"The whole team was awesome. Justin was super helpful in helping us pick windows and answered all our questions. We had the whole house done and the installation crew were professional and hardworking. We noticed a difference right away with how quiet the windows made the house. We also noticed that the house has a more even temperature between levels. I am excited to go into winter now with a great set of windows that are so easy to use and with quality installation that will last.”

- Jordan M.
Johnson County Siding & Window Co.
"It was a most pleasant experience to work with Johnson County Siding and Windows for the replacement of a few windows in our home. Bill Christie came and gave us a price. No glib, "well this is what it cost, but we can do it for this if you pay cash right now ..., but, no, wait, we can do this, if you hurry ... " He sold his product, and company, with pride and experience. The team to install, lead by Justin, arrived early on the appointed day. They went right to work and completed the task in due order, answering any questions we could have, and explaining the total function of the system. They cleaned up after themselves, and left the windows shining! What a day! Thank you Bill, Justin, William and Brian!”

- Elizabeth H.
Johnson County Siding & Window Co.
"Company did an excellent job re-siding our house with vinyl siding. Experienced crew took the time to clean up every evening after completing the work for the day. No high pressure sales tactics. Payment terms did not require any money up front when contract was signed.”

- Mark K.

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