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.
"I had Johnson County Siding & Window install siding, replace all the windows (except for one that had been replaced recently), install new front and back doors, replace a deck, and replace the front step's railing. The jobs were very well done and the crews were all friendly and professional. I would certainly do business with them again.”

- Luke N.
Johnson County Siding & Window Co.
"Top notch service and workmanship. Installed vinyl siding on our our house 4 years ago and have been very pleased with it since. Yesterday I called for repair service. Bill responded in a very timely manner, within an hour. Repairman was scheduled to arrive early the next morning and arrived as promised. Justin W. preformed the requested repairs timely, was very professional and courteous. Very pleased with JoCo Siding and Window's service and workmanship.”

- Dale D.
Johnson County Siding & Window Co.
"This is the second house that I've had them put Hardie siding on. They do a great job, exactly as quoted and discussed. The workmanship and painting were excellent.”

- Malcolm M.

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Serving the Kansas City Metro Area, Including Olathe, Overland Park, and Leawood See a Full List of the Cities We Serve