Patio doors are a beautiful addition to any home, and they have many benefits. Unfortunately, patio doors are also notorious for allowing energy to escape your home. If you have an older patio door, check out these five facts about patio doors and energy efficiency.
Patio Doors Lose a Lot of Heat
Patio doors, whether they are sliding, swinging or folding, generally have a lot of glass, which is great for letting in light and making the room look bigger. However, glass doesn't block the transfer of heat well. Heat passes through glass in three ways: conduction, radiation and convection. Conduction refers to how much heat actually passes directly through the glass. Radiant transfer is the transfer of heat via long-wave energy, such as UV rays. Last, convection is the glass stealing heat from hot air in your home. As warm air hits the window, it gives up its heat, cools and falls. Hot air moves in to take its place only to give up its heat too.
You Can Improve Your Existing Doors With a Few Modifications
The best way to improve your patio door's energy efficiency is to replace it, but if you don't want to or can't afford it, there are some steps you can take to improve your current patio doors. Start by placing low-E window film on the glass, which block radiant heat transfer. Next, replace old, warn weather-stripping to help create a tighter seal when the door is shut. The last option is to install an awning over the patio door, which can help stop some direct sunlight from hitting the window.
Newer Metal-Framed Glass Doors Have a Thermal Break
Metal isn't the most insulating material out there, because it is extremely conductive. If you have an older patio door with a metal frame, you're probably losing a lot of heat through the frame. Newer metal-framed glass doors, however, have a thermal break between the inner and outer frame pieces. This plastic insulator helps stop heat from traveling through both pieces of metal and out of your house (or inside your house during the summer). Of course, vinyl is still the most energy-efficient framing material, but thanks to these thermal breaks, you can have an energy-efficient metal patio door.
Better Models Have Better Energy-Efficient Features
Regardless of which type of framing material you choose, there are ways you can hinder the transfer of heat through the glass, which makes any patio door more energy-efficient. One option is to have a low-E coating applied to the glass. The low-E coating is much like the low-E window films, but the coating is more effective at blocking UV rays and other invisible light. Another way to drastically improve energy efficiency is to choose double- or triple-paned doors that have insulating gasses between the panes. Gasses like argon and krypton block the transfer of heat through the glass.
The U-Factor and SHGC Can Help You Choose the Right Door
When looking at patio doors, check the U-factor and the Solar Heat Gain Coefficient (SHGC). To be considered Energy Star, doors must meet certain ratings, and if you choose an Energy Star certified door, you know you're getting one that is energy efficient. The U-factor refers to how much heat and cold pass through the door, and the SHGC measures how much heat from the sun passes through the glass. Depending on the glazing level, the U-factor should be between 0.17 and 0.30, while the SHGC should be between 0.25 and 0.40.
You don't have to let your patio doors waste energy. There are ways to improve your existing patio door, but your best bet is to get a newer one with Energy Star certification. For more information about energy-efficient patio doors, contact a contractor in your area today.