Glass, Glazing and Gas: 3 Factors of Energy Efficient Windows

Advanced window technology can minimize heating and cooling costs.

For anyone interested in one of the best unions of all time, it's important to look at the marriage of gas and glass in window and door units.

Why is such a marriage of importance to the average homeowner? Because it can either save you — or cost you — hundreds of dollars each year on heating and cooling bills. The union of gas and glass firmly stands together to block harmful ultraviolet sunrays and heat transfer, major causes of high energy costs, faded flooring and condensation buildup.

Homeowners selecting windows and doors for new homes or as replacement units need to fully understand the construction of fenestration products and their potential cost-saving benefits. That's the advice of Bill Lazor, senior product manager at Simonton Windows.

"In this age of advanced technology, it's unthinkable and unwise for anyone to have just plain glass in their windows or doors," says Bill. "[Plain] glass offers no protection at all from ultraviolet rays coming into the home that can cause fading of carpets and furnishings. Plus your heater and air conditioner work harder to keep the home comfortable when only plain glass is used in windows."

According to Bill, the ideal selection for homeowners is to specify an IGU (insulated glass unit) made of at least two pieces of annealed glass sandwiched together with a thermal spacer and then filled with either an argon or krypton gas. Denser than air, these odorless, nontoxic gases act as invisible barriers to prevent damaging UV rays and extreme temperatures from entering the home. Similarly, the IGU helps prevent the comfortable, climate-controlled air in the home from escaping to the outdoors.

"If you want to have a highly energy-efficient home, consider glazing and gas options when thinking about your windows," Bill says. "Low E glass is a 'must' if you want to maximize the energy efficiency of your windows. Tinted and clear glazings (or coatings) help prevent the transference of heat, cold and sunlight into the home. That's one reason why Low-E coatings are so popular. A gas-filled insulating unit, where the invisible gas is hermetically sealed in the window unit using spacer systems, is an excellent barrier." And the more barriers that separate the inside of your house from the exterior, he adds, the stronger the protection from heat gain or loss.

Concerned about the idea of having gases in your windows? Don't be. The two most popular gas fillers for windows, argon and krypton, already are present in the air we breathe. Furthermore, the units are carefully sealed so the gas won't leak out. Furthermore, the gases help reduce heat transfer between the glazing layers, cutting the chance for condensation on the interior and exterior of your windows.

"Homeowners need to fully understand the construction and options involved with windows before making a major purchase," says Bill. He encourages contractors and homeowners to visit the websites, and to determine what will work best for in their areas.

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