Choosing Doors and Windows for Energy Efficiency


Whether you’re building a new house or upgrading your home, there are many factors to consider when choosing the right windows and doors for your home. Some may seem obvious, but lesser-known considerations can affect energy efficiency. This article will cover what you need to know about window and door materials, air leakage ratings, and other factors that can make or break an investment in new windows or doors.

Pay Attention to Window Frame Materials

Pay attention to the materials used to make your windows and doors. The material will determine how much energy gets through and how much heat is lost. Different materials offer different levels of thermal resistance.


  • Wood frames provide excellent insulation and are great at keeping heat or cold outside your home.
  • Fiberglass frames offer similar insulation properties to wood.
  • Vinyl frames can help reduce heat loss, providing better energy efficiency.
  • Aluminum frames might be inexpensive and durable but have poor insulation ratings.


Choose Double- or Triple-Pane Options

If you’re looking to save on your energy bills and reduce your carbon footprint, it’s worth investing in a high-quality window. Double- or triple-pane windows are better than single-pane options—and the more panes you have, the more efficient they’ll be.

If you want to go even further, consider choosing low-emissivity (or “Low-E”) glass with low infrared heat radiation levels. This can help keep rooms cooler during summer by reflecting some of the sun’s heat outside through the glass pane. Low-E glazing also filters ultraviolet rays from sunlight; this helps prevent damage to artwork and furniture and reduces glare inside buildings on sunny days.

Learn About U-Factors and Solar Heat Gains

Look for options with a lower solar heat gain coefficient (SHGC). SHGC is a measure of how much solar radiation passes through windows. A window with an SHGC of 0.4 and overall transparency of 80% means that only 20% of the sun’s energy will come through and into your home. The lower number is, the less heat gain you’ll experience throughout the day.

U-factor is a measure of how much heat passes through a window. Knowing what U-factor you’re getting is important because the lower it is, the better the window will keep heat in and out. The best windows have a U-factor as low as 0.3; if your window has a higher U-factor, it’s not properly insulated. A high U-factor means significant amounts of heat can escape through your windows when they’re not shut tight.

Don’t Forget About the Door

Even if you install energy-efficient windows throughout your home, failing to install energy-efficient doors will result in air leaks that can let cold or heat inside your home. Consider doors long-term investments. In this case, choosing iron doors might be an energy-efficient solution that brings you benefits for years to come. 

Because iron doors are often paired with glass, you can choose double- or triple-pane glasses with low-E and all the benefits of insulated glass. As a result, you get a door that not only doesn’t let sun heat come through but prevents air from leaking inside your home. 

There are many factors to consider when replacing windows or doors, but you can be confident if you’ve done your research first. As our energy efficiency guide mentioned, ensure that any replacement option has Low-E glass or triple-pane construction. These features will help keep your home warmer during cold weather while reducing heat loss during hot summer months compared with single-pane options.

Written by Geraldine Orentas