Aluminum replacement windows have dropped to near-niche status, only accounting for roughly 2 percent of the replacement window market according to the American Architectural Manufacturers Association (AAMA).That's eclipsed by fiberglass, at 2.6 percent of the replacement market, and dwarfed by vinyl, which accounts for almost three-quarters of all replacement windows installed.
Major reasons for aluminum's low popularity include is its less-than stellar image (more on that below) and its much lower energy efficiency compared to most other replacement window types, including wood, clad-wood, vinyl and fiberglass. That leads to more heat transferred to the outside during cold days, and condensation -- and in extreme cases even frost -- forming on the inside, especially if low-efficiency glass is also used.
To combat their propensity to transfer heat, the best aluminum replacement windows use thermal break frames. Those place an insulating material between the inside and outside of the aluminum frame, greatly improving energy efficiency, though it still falls behind that of other replacement windows. If getting the best energy efficiency from aluminum windows is a concern, homeowners should opt for the highest efficiency glass that the window vendor offers.
Still, those living in areas subject to cold temperatures in the winter should probably look elsewhere, and many vendors will not offer their aluminum window products in regions where they won't meet local energy codes. However, aluminum replacement windows can make for a reasonable choice for those living in milder climates, such as in the American South, and experts say that aluminum replacement windows have some significant advantages.
For starters, they are lightweight yet very strong, and they can withstand high winds as well as temperature extremes without losing their integrity. "For homeowners living in areas prone to hurricanes and high winds, impact-resistant aluminum windows have grown in appeal over the years." notes Angie Hicks, owner and publisher of the Angie's List website. She says that while impact-resistant vinyl replacement windows are available, they generally cost more than aluminum.
Experts also note that modern aluminum windows are a far cry from the less-than-well-regarded ones of the not-too-distant past. "When you hear 'aluminum windows,' the first thing that comes to mind is the cheesy, usually ugly products that were the hallmark of bad late-20th-century construction and remodels-on-the-cheap of fine old homes," note the experts at CalFinder.com, a contractor referral website. "In fact, aluminum windows have come a long way in recent years, and can be positively stylish," they add.
Most recently, aluminum windows have actually become the darlings of some architects and builders for their clean lines and strength, allowing for thin frames and larger expanses of glass. You can count the architects at Washington state's Build LLC among aluminum's fans: "We use aluminum windows for a bunch of reasons: they're extremely functional, maintenance free, and complement the attenuated clean lines of modern design."
They are also a fitting choice for many mid-century homes. "If your house was originally built with aluminum windows -- most postwar houses from the mid-1950s through the 1980s were -- there's no question that new-generation aluminum windows will be your best aesthetic choice for replacement," says Arrol Gellner at Inman News, a news site for real estate agents and brokers.
Though aluminum replacement windows are often touted as needing no regular maintenance, that's not necessarily correct. Over time, they can suffer from the effects of the weather and show pitting or corrosion. That's a particular concern in coastal areas with their salt air. However, unlike vinyl, aluminum can be easily primed and painted to any color. Most windows can also be ordered with baked on enamel or powder-coated finishes. "Some manufacturers also offer vinyl-clad aluminum windows, an option that reduces maintenance to practically nil," CalFinder.com says.
Aluminum windows aren't offered by as many vendors as other types, but if they work for your climate and your home's design, you can get aluminum replacement windows from a variety of national, regional, and local manufacturers. Top national names include Milgard and Jeld-Wen.