The drive for more energy-efficient solutions in the residential door market has left aluminum struggling to grow—or even maintain—its market share, although the metal's recyclability and other characteristics make it ideal for certain niche applications.
"Aluminum is just not one of the greatest performing materials when it comes to energy efficiency," said Casey Pope, product manager at Jeld-Wen Windows & Doors, Klamath Falls, Ore., noting that aluminum is used in residential door applications mainly in certain warmer climates, such as the Southwest and in southern Florida, where structural stability is a big plus. But elsewhere, vinyl has the lion's share of the market.
John Mitchell, vice president of sales and marketing at Nichols Aluminum LLC, said that less than 10 million pounds of aluminum is consumed each year in North America for residential windows, doors and skylights, with far more aluminum used for windows than doors.
This is in strong contrast to the commercial door market, where aluminum is the material of choice, accounting for almost half of the sector, according to Libby Magliolo, spokeswoman for the Schaumburg, Ill.-based American Architectural Manufacturers Association.
"Aluminum can be used as part of the solution for residential doors," said Jerome Lucaes, director of strategic marketing for North America at Montreal-based Rio Tinto Alcan. Aluminum brings with it several potential advantages, including rigidity, thermal efficiency, strength, durability and the potential for different design solutions, he said.
"While there is heat loss with an aluminum door without the use of a thermal barrier, with a good thermal break and glazing, aluminum doors are extremely energy efficient. Aluminum allows for better indoor quality and an improved carbon footprint, given its recyclability," Lucaes said, noting that 95 percent of all aluminum used in building and construction is recycled.
"It isn't just recyclable, but it gets recycled. The aluminum ore (bauxite) also is much more abundant, with no risk of depletion, unlike oil-based materials such as vinyl," he said. "Also, with aluminum you can provide a thin, nicely shaped architectural design to the doors. Because of the stiffness of aluminum you can use a narrow frame around glass, which allows more space for light to come in."
The range of colors is one major advantage, Magliolo said. "One of the main advantages to aluminum is the wide range of colors available. Colors of products can be specially made in order to match existing architecture or trim. Aluminum products can be customized with painted finishes, which are available in either liquid or powder form and come in an almost endless assortment of color options. Anodized finishes on aluminum products form a protective coating of aluminum oxide on the surface of the aluminum profile. Anodizing finishes are one of the hardest substances known to man—comparable to the hardness of diamonds."
Meanwhile, Mitchell said, "vinyl discolors easily. It doesn't stand up to ultraviolet rays and tends to have a cheaper appearance than aluminum."
But how long this will be true remains to be seen. "There have been some advances in vinyl coatings that would allow vinyl to catch up on that front," Pope said.
Sliding doors and storm doors represent the two major applications for aluminum in the residential door market, according to Lynn Brown, senior vice president of sales and marketing at Hydro Aluminum North America Inc.'s Linthicum, Md.-based Extrusion Americas business unit.
Aluminum maintains niche uses in sliding doors despite having been largely pushed out of that market three to five years ago by vinyl and aluminum-clad wood. "It has, however, retained certain niches, such as areas where building codes require higher hurricane resistance ratings and where there is a need for noise mitigation," Brown said. "Vinyl is a cheaper way to comply with certain energy standards that have been written in a way that favors vinyl and wood."
And aluminum faces further pressure as new national energy codes from the International Energy Code Council are adopted on a state-by-state basis.
"In Florida, where structural integrity is very important because of all the hurricane activity, aluminum is currently a dominant material for patio sliding and swinging doors," said Debbie LaPinska, vice president of sales and marketing at PGT Industries Inc., North Venice, Fla., noting that while aluminum isn't currently gaining any market share it is at least holding its own.
Aluminum has a bit more potential to at least maintain its market share in residential storm doors, which are a regional product used mainly in colder areas of the country, such as the Northeast and Midwest, Brown said.
"Aluminum extrusions lend themselves well to the manufacturing process to make storm doors as you can use only a relatively small frame and you can put a lot of detail into that frame," he said. "It is a good marriage of end process and product demand. Not only does aluminum provide good strength, but there is a great bit of flexibility in the extrusion process to create shapes that customers want for that kind of product." MYRA PINKHAM