August 2005

Volume 6 Issue 7 August 2005

AAMA ANALYSIS

Don't Cut Aluminum Out
Material is Ideal for Residential Applications
by Larry Livermore

Although still the unquestioned ruler of fenestration for commercial and architectural applications, aluminum’s market share for both new construction and remodeling in the residential sector has been eroding steadily. This is due primarily to an increase of vinyl-framed product. But there seems to be a variety of niche residential markets that will provide a bastion of demand for aluminum products for many years to come.

Will Winds Blow Some Good?
Consider, for example, code requirements for windows used in dwellings in coastal regions subject to hurricanes. Spurred by the incredible damage wrought in Florida by a succession of four storms in 2004, the Sunshine State has led the way in ratcheting up codes to require stronger and more durable fenestration. The market is large, as decades of explosive development on barrier islands and other coastal zones since the 1970s has more than doubled the population in these at-risk areas.

The Charley- Frances- Ivan-and-Jeanne quartet administered a harsh lesson: adequate protection of windows must go beyond withstanding excessive wind loading to holding up against the impact of airborne debris. The code repercussions could reach well beyond Florida and the Atlantic and Gulf coasts—perhaps even into the Tornado Alley regions of the Midwest.

Aluminum’s inherent structural strength—long the backbone of its dominance for commercial and architectural projects, combined with laminated glazing, make it a viable option for meeting these new code requirements and test standards (notably Miami-Dade standards PA-201, PA-202 and PA-203, and ASTM standards E 1886 and E 1996).

Aluminum also boasts immense stiffness. This means aluminum has excellent resistance to deformation, or bending, which is why it is often used as a reinforcing element in window frames made with other materials.

Movin’ On Up
High-end residential applications offer solid markets for aluminum products, too, especially in luxury and contemporary dwellings and for historical restoration applications.
The adaptation of commercial structural glazing technology, once the province of only commercial and high-rise projects, offers new design options, especially when combined with trendy European tilt-and-turn operable sash. Supported by strong aluminum framing members, both operable and fixed units can be combined into expanses of glazing several feet wide with a curtainwall-type appearance in which all modules of glass have a consistent perimeter frame.

In the historical restoration market, aluminum’s ability to be precision-shaped means that new windows can duplicate the delicate shapes and sightlines accurately of the original windows, while delivering the benefits of improved energy-efficiency, low cost and low maintenance. Rigid tubular shapes, better integrated muntin systems and custom-profiled exterior trims and panning make aluminum particularly useful in replicating vintage casements and double-hungs.

Aluminum extrusions can be made deeper; as opposed to increasing the sightlines, while still accommodating thermal breaks, insulating glass and weatherstrip channels. This allows for the development of products with smaller historically-appropriate sightlines while still providing the structural and thermal requirements of commercial projects.

Applying structural glazing technology to bond the glass to narrow sash members can also produce thinner exterior profiles that duplicate the characteristic putty slopes of the old-style steel casements. This approach can be used to replicate historic double-hungs in exclusive suburban markets.

It’s Easy Being Green
Another trend in favor of a potential boost for aluminum fenestration is the green building movement. With its well-recognized recyclability and refabrication energy cost of only 5 percent of that required for the production of the original material from ore, aluminum passes sustainability tests easily.

Strength, adaptability and solid green credentials are causing many to re-evaluate aluminum products for specific residential applications. Manufacturers might be well-advised to consider catering to architects, builders and contractors who must address the requirements of these unique market segments.

Larry Livermore serves as technical standards manager for the American Architectural Manufacturers Association in Schaumburg, Ill.