The Best Window Glass Options for Southern Climates

When it comes to windows for those in the Southeast, you want quality windows that can help keep out the heat while you stay cool. And if you’re near the coast, you’re also thinking about potential storms or hurricanes. So what are the best windows for the climate in the Southeast?

First, let’s identify what windows can help keep out the heat. The type and thickness of glass both factor into the overall energy efficiency of the window. Let’s examine each one.

Number of layers

Every window has a pane. But what you may not realize is that some windows contain multiple panes of glass. Double-pane or triple-pane glass gives you better insulation and helps block the heat of the sun. Between each pane of glass is usually some form of insulating glass, like argon. This kind of gas has higher resistance to heat flow than air, helping to improve the thermal performance of the window.

Types of glass

In addition to the number of window panes and insulating gas, you should also consider the type of window glass you buy. Some windows are designed specifically to block the heat of the sun and reduce ultraviolet rays, which can warm your house leading to potential increased cooling costs.

Low-E glass

One option for glass that lessens the passage of heat through your window is Low-E glass, which stands for low emissivity glass. Low-E glass has a special coating that helps block out most ultraviolet (UV) light and infrared (IR) light while still allowing the majority of visible light to pass through. Controlling IR light increases control over the passage of heat through your window. When it comes down to it, Low-E glass can help maintain your home's temperature and increase energy efficiency. Low-E glass windows are becoming increasingly popular, especially in hot climates.

Impact-resistant glass

Homes in the Southeast may also need to consider impact-resistant glass for potential storms or hurricanes. Impact-resistant glass (also known as hurricane glass) can help protect you and your family from high winds and threatening storms.

Hurricane glass is also made to resist high-velocity projectiles, and while the glass portion of the windows can shatter as the result of an impact, the interlayer will help keep the window intact. Impact-resistant glass also reduces UV transmission, helping to keep the hot air out and cool air in.

NFRC label

As you purchase windows for your home, you’ll want to look at the windows’ NFRC label. NFRC stands for National Fenestration Rating Council® (NFRC), the organization that developed an energy rating program for windows. It’s a reliable way to determine a window’s energy performance. Reputable window manufacturers rate and certify their products with these three requirements.

U-Factor

U-Factor measures the rate of heat flow through the window. The lower the number on the NFRC label, the better the window is at keeping heat in.

Solar Heat Gain Coefficient (SHGC)

SHGC tells you how much solar heat comes through the window. The lower the number, the less solar heat comes in.

Visible Transmittance (VT)

VT is how much natural light the window lets in during the daytime. The higher the number, the more natural light you’ll get.

For the hot Southeast, you’ll want to look for windows that have a low U-Factor number, a low SHGC number, and a high VT number. That way, your window can let in the natural light while reducing solar heat compared to a window with a higher SHGC.

Finding a window that can help keep your home cool in the summertime isn’t an easy task, but with these tips in mind, you’re well on your way to choosing a quality window. Here’s another practical tip: Consider buying Pella's SunDefense™ Low-E Insulating Glass with Argon. It's designed for hot and sunny climates to help keep the heat out and let the light in.