Best Type of Window for Energy Efficiency

As an energy-conscious homeowner, you know the type of window you invest in can cut down on utility bills, provide year-round comfort, and reduce your carbon footprint.

The problem is, choosing the perfect energy-efficient windows can be overwhelming with so many choices on the market, and you want to make sure to get the most bang for your buck. So, what exactly is the best type of window for energy efficiency?

The best type of window for energy efficiency has double or triple-paned glass windows, low emissivity glass coatings, krypton or argon gas filling between window panes, and have high-quality window frames. You must also install energy-efficient windows properly to see the benefits.

These energy-efficient features, when combined, create the ultimate energy-saving window. 

Before we dive into the best window types for energy efficiency, let’s look at the main five factors that influence the overall energy efficiency.

Four Factors that Influence Energy Efficiency

Four main factors determine how new or replacement energy-efficient windows perform – check them out:

The Window Glass

There are three areas to consider when it comes to the glass used in energy-efficient windows:

  • No Pane, No Gain: Windows with dual-pane glass insulate nearly twice as effective as single-pane. Triple-pane glass is even more energy-efficient.
  • Gas is Good: Argon, krypton, or other gases (odorless, colorless, and non-toxic) are filled between window panes, increasing your home’s insulation abilities.
  • Always Take the High Road, But Go Low With Low-Emissivity Glass Coatings: Keep the sunshine, but forget the infrared and ultraviolet light – heat, in other words. Low-e glass coatings effectively keep the heat outside of your home during the blazing summer months and inside where you want it during the long, cold winter months.  

The Window Frame

Window frame material impacts how effective your windows will be when it comes to energy-efficiency.

  • Wood:  Wood has low thermal conductivity, so frames made of wood transfer lease cold and heat. While many homeowners and experts prefer wood because of the excellent insulation, it requires more upkeep than other materials. 
  • Fiberglass: Fiberglass is a strong material – more so than wood or vinyl, and won’t warp or crack as it’s able to withstand contraction and expansion. Fiberglass is more energy-efficient than vinyl or aluminum and is easy to care for.
  • Vinyl: Vinyl is a practical, cost-effective, low-maintenance option that can provide excellent energy-efficient measures if well-constructed and adequately installed. There are fewer design and color options when it comes to vinyl, however.
  • Aluminum: Aluminum is a top choice for humid, wet regions as the material is strong, durable, and resistant to the elements. However, aluminum does not offer the heat transfer and loss qualities other materials do.
  • Wood-Clad: Wood-clad windows typically have a vinyl or aluminum exterior, making it low maintenance, and an interior made of wood, providing the low thermal conductivity that is energy-efficient.

Choosing a high-quality frame will improve your window’s overall energy efficiency.

Window Installation

Energy-efficient windows are an investment. You’ve picked the perfect window glass and frame and can’t wait to see the savings. Unfortunately, if your contractor does not install your windows properly, none of that is going to matter.

Make sure you hire a licensed, reputable installation crew. Get several quotes, read reviews, and make sure the contractor has the experience and offers a warranty on their work.  


Where do you live? What’s the climate like? 

The type of window glass and frame you should go with is most definitely related to your region and the climate.

For example, you might want to go with a low-E coating, applied in reverse, if you live in the north and experience cold or freezing weather.

Talk to your window manufacturer to determine what kinds of energy-efficient glass and frames are available that suit your specific region’s needs.

Types of Windows

The type of window itself matters when it comes to energy efficiency. There are picture windows, casement windows, double-hung windows, and more. Which one is the most energy-efficient? Take a look:

Picture windows

Picture windows, also known as fixed windows, don’t open. They come in many different sizes and shapes and can be incredibly energy-efficient with the right glass and gas-filling.

ENERGY STAR’s most energy-efficient picture window is from American Window Systems’ EnergyCore window line. The company’s picture window’s innovative frame design has patent-pending fusion-insulated AirCell™ technology, a high-performance low-E glass standard, and insulated glass that helps reduce condensation.

Casement Windows

Casement windows are incredibly energy-efficient as their seal is tight and strong. This type of window has a crank that allows you to open the window.

Casement windows require maintenance to make sure that they stay as energy-efficient as possible. 

The highest-rated casement window, according to ENERGY STAR, is from American Window Systems’ EnergyCore line. This encasement window also has the AirCell™ frame design, high-performance low-E glass standard, and has multiple weatherstrip rows. 

Double-hung windows

The bottom part of the double-hung windows opens. You see these types of windows commonly in traditional homes. 

While they can be energy-efficient, they allow air to enter through the sliders that move the bottom part of the window up and down.

According to ENERGY STAR, the most energy-efficient double-hung window is also from American Window Systems’. It is the EnergyCore Double Hung Vertical Slider, which has interlocking, reinforced meeting rails and dual weep sill drainage. These double hung windows also have Aircell™ technology and low-E glass that performs like no other.

Tip: Look for the ENERGY STAR Label 

If your window has a sticker with the ENERGY STAR label, you likely chose an energy-efficient product. The United States Environmental Protection Agency (EPA) helps people like you save money by maintaining superior energy efficiency standards.

In Conclusion

You are a smart, energy-conscious homeowner that now knows to move forward choosing the best energy-efficient window.

Just keep in mind that there are several critical factors to take into consideration when looking for energy-saving windows that fit your criteria as well as your budget. 

Good luck finding the perfectly energy-efficient windows for your home!