Everything You Need to Know About the Glass Used in Patio Doors

“Installing a new patio door instantly boosts your home’s property value plus enhances its architectural presence,” said Christopher Wittmann, Master Certified Remodeler and Senior Sales Associate with Callen.

In the most basic sense, there are generally two types of patio doors, hinged and sliding, while there are several material components involved in the construction process, such as hardware, exterior and interior finishes, exterior trim, and screens. “One of the most important aspects of patio doors is the glass used,” Christopher said. “The construction of the glass doors, including the number of glass panes, the use of argon gas, and the type of coating applied to the glass will have a direct impact on your home’s overall energy efficiency and the patio door’s ability to filter out harmful UV rays.”

A climate like southeastern Wisconsin’s sees a diverse range of severe weather and extreme temperatures, which means a home’s patio doors must be properly insulated in order maintain a comfortable indoor air environment and maximize overall energy efficiency year-round. “For instance, dual pane glass, which is considered a standard and more common feature on most modern patio doors, is far more successful at insulating and protecting your home from the outside elements than single pane glass,” said Christopher. Taking things a step further, “while triple pane glass is another option for maximum protection against inclement weather and harsh temperatures, the return on investment of triple pane glass may not be immediate in our direct climate,” he said.

It’s important to note that the number of panes of glass alone does not determine a patio door’s energy efficiency. There are other factors involved, such as argon gas, which is used to fill the spaces between the glass panes inside the patio door. “Argon gas adds an extra layer of insulation and assists in preventing heat loss,” said Christopher.

The type of coating applied to the glass also plays a part in a patio door’s energy efficiency. Referred to as low emissivity (Low E), these ultra-thin metallic coatings are applied directly to the glass in layers to reflect the sun’s heat as well as protect the home from harmful UV rays, all while allowing the visible light to pass through.

“When considering each type of coating, it’s important to examine two factors: heat transference from the sun to your home and radiant heat, or the ability of the coating to keep the heat on the same side of the glass in which it’s being generated,” Christopher said.

Low E1 coating prioritizes keeping a home heated versus cooled, Low E2 offers year-round performance in moderate climates to help retain heat in your home during the winter and keep heat out during the summer, and Low E3 rejects solar heat while letting light in, resulting in increased performance in climates with intense sun exposure. “We live in a unique climate, so it’s important to fully understand how new patio doors are going to stand up to the elements, no matter the forecast,” said Christopher. “Therefore, it’s important to confirm the following before making your final decision on your home’s new patio doors: the number of panes of glass there are, whether or not a gas is used to fill in the space between the panes of glass for added insulation, what type of Low E coating is applied to the glass doors, and which style of decorative glass best aligns with your personal preference and your home’s style.”

If you’re interested in new patio doors, call Callen today.