METAL MATTERS

The Growth of Green
The Role Fenestration Plays in Sustainable Design
by Ken Brenden

While “green” has become a term and topic of interest in recent years, a closer look reveals that the reasons to pursue green construction extend far beyond the nebulous idea of being more environmentally friendly. Besides minimizing a building’s carbon footprint, the benefits of green building range from improved aesthetics to decreasing operating costs and even gaining tax credits by using sustainable building materials.

Even in this difficult economy green building has proved to be one of the growing bright spots for the United States. In fact, McGraw-Hill Construction’s Green Outlook 2009 report states that the value of green building construction starts was up five-fold from 2005 to 2008 and could triple by 2013.

Cost Matters
An initial question that arises in approaching a green building project is how much more sustainable construction will add to the project budget. A 2008 study sponsored by the U.S. Green Building Council (USGBC) found that a Leadership in Energy and Environmental Design (LEED™) certified building costs an average of 2.5 percent more up front than traditional construction—not the 10- to 20-percent premium estimated by most developers. That cost is also coming down.

While the most successful green building projects have all building components working as part of an integrated whole, fenestration plays a key role in energy-efficient and environmentally-friendly buildings. This role extends beyond selecting and installing fenestration products to also include even the basic design of a building and the placement of doors and windows to maximize daylighting effects.

“Even in this difficult economy green building has proved to be one of the growing

bright spots for the United States.”

Energy Saving Solutions
The integration of daylighting is indeed a major aspect of green building and studies have concluded that daylighting provides a range of positive effects from increased productivity to improved health. Natural light reduces energy demand by reducing dependency on electric lighting as well as the heat load that electric lighting places on a building’s comfort cooling system. To reduce solar heat gain, for example, high-efficiency, insulating, low-E coated glass is used. This is an area where any initial increased costs associated with green or sustainable construction can be recovered quickly in decreased energy consumption and overall operating costs. Improving aspects of building performance and decreasing overall operating costs proves attractive for investors and tenants alike.

For commercial framing systems, one material of choice for architects and builders has been aluminum. Aluminum frames are engineered with effective thermal barriers between inner and outer frame elements to reduce heat flow. Aluminum also has well-established recyclability; products made with recycled aluminum embody only about 5 percent of the energy needed to make primary aluminum, and the raw material (bauxite) is plentiful. Aluminum is also high in strength while low in weight.

Beyond Energy Performance
Fenestration products also perform well in regard to other green attributes besides energy efficiency. For example, doors and windows made from abundant, recycled, recyclable or renewable resources typically earn green credits for life cycle impact. Programs such as LEED recognize not only efforts toward energy-efficient buildings, but also indoor environmental quality as well as ample daylight and views.

In addition, LEED awards points for manufacturers’ recycling practices and their proximity to jobsites (decreasing transportation impacts).

With the myriad of benefits that come along with green building, it is clear that sustainable design and green construction are becoming the norm, rather than the exception, and certainly a trend of which we will be seeing more in the coming years. AG

Ken Brenden is the technical services manager for the American Architectural Manufacturers Association (AAMA) based in Schaumburg, Ill. Mr. Brenden’s opinions are solely his own and not necessarily those of this magazine.

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