Advanced Sustainability Potential Using Metal Building Systems
ENERGY PERFORMANCE PROJECT – NEW CONSTRUCTION
Photo courtesy of MBMA
Project: Alamo Beer Company
Location: San Antonio, Texas
Architect: Lake|Flato
Energy Performance: Designed for high performance, the 18,000-square-foot facility operates without air conditioning and boasts a project energy use intensity that’s 77 percent lower than similar building types. “You might not think it, but metal building systems are very sustainable,” architect Greg Papay says. “That’s what I admire most about them—they’ve been refined to a point where they’re economical, efficient and beautiful. They capture all the aspects of what a building should be.”
ENERGY PERFORMANCE PROJECT – RENOVATION
Photo courtesy of MBMA
Project: Thunder Road Harley-Davidson
Location: Windsor, Ontario, Canada
Architect: Architectural Design Associates Inc.
The Project: This thriving dealership needed to expand and during their travels throughout North America, owners Chris and Carol O’Neil noted the quality of the Harley-Davidson dealerships that were housed in metal buildings. Now, they have one of their own.
The Design: Their nearly 20,000-square-foot building structure combines a retail showroom and service department under one roof. The open-concept showroom makes it easy to display products and to reconfigure at will.
Energy Results: Despite having 50 percent more space than their previous facility, Thunder Road’s heating costs dropped by one-third. “That’s a testament to how well-built the structure is,” Chris O’Neil says. The metal roof, due to its expandability and weathertight seam, offered additional protection for the dealership’s high-value inventory while reducing energy costs. The couple subsequently added solar panels which attached easily to the metal roof and further increased their energy savings.
Renewable Energy Production
In addition to energy conservation measures, LEED provides up to 3 credits for on-site production of renewable energy such as Solar Photovoltaic (PV) solar thermal systems. Such units attached to a metal roof profile provide an exceptional platform for renewable energy production. PV electric and solar water-heating systems are more economical than ever before and offer a ready opportunity to generate on-site renewable energy. Metal buildings that use standing-seam metal roofing provide an ideal platform for such systems due to the ease of mounting PV arrays and the longevity of the standing-seam metal roofing system, both of which translate to significant cost savings. Solar panels are installed on a standing-seam metal roof with clips that lock directly onto the seams and are hidden from view. The clips do not require any penetration of the roof, avoiding any potential for water seepage. Since a metal roof generally provides a service life of 60 years or more, outlasting the PV system (with a typical life of 25-30 years), their use avoids roof replacements during the tenure of most PV arrays.
Materials and Resources
The materials used in any building have an environmental impact throughout their life cycle. LEED and other sustainability programs recognize this in a variety of ways, with metal buildings consistently offering some strong solutions to reducing the impact from the materials used. Four methods are summarized in the following sections.
RENEWABLE ENERGY NEW CONSTRUCTION PROJECT
Photo courtesy of MBMA
Project: Hangar 25, Bob Hope Airport
Location: Burbank, California
Architect: J.R. Miller & Associates
The Project: The $17-million building has 50,630 square feet of hangar space, plus approximately 12,000 square feet of office and meeting area space.
The Design: The hangar is a metal building system including a metal roof and metal wall panels that incorporate a multitude of sustainable features. In the quest for efficiency, the structural members in this metal building system are custom engineered to handle the specific load needs for Hangar 25. This optimizes the steel used in the building which reduces costs.
Energy Systems: A 225-kW photovoltaic (PV) system is mounted to a standard R-panel roof on a rack system that attaches to the purlins. An added benefit of the 1,500 PV panels system is the shading it provides to the roof. This helps keep cooling costs down and, along with the highly reflective white metal roof panels, reduces the heat island effect. The roof is considered a cool roof, with a solar reflectance of 0.70, an infrared emittance of 0.85, and a solar reflective index (SRI) of 85. The solar array produces 110 percent of the power needed to operate the facility and is expected to produce more than 400,000 kWh of energy per year. The electricity savings from the solar array are significant. The building has operating expenses that are approximately 2 cents per square foot, compared to a traditional hangar that operates at about 20 cents per square foot. In addition to building operations, all the equipment for the hangar, including rechargeable tractors, forklifts, and tugs, run off the electricity produced by the solar array. Further, when aircraft receive maintenance, the power to keep all the systems running comes from the solar array. Using the solar power is not only cost-effective, but it also does away with fumes and odors from the diesel and jet fuel that would ordinarily be required.
Other LEED Strategies: Other energy enhancing features include: six large, metal fans suspended from the building’s steel frame provide a low-cost system for circulating air; more than 100 translucent panels in the metal roof, keep lighting costs down and more than 95 percent of the regularly used areas of the facility, including the office space, receive natural daylight; the polished, natural concrete floor is chemical-free and estimated to last at least 20 years, and those who work here won’t have to worry about toxic compounds. The hangar gained valuable LEED points for its recycled content, with recycled steel used for the primary structural members.
The Results: Hangar 25 is world’s first LEED Platinum certified aircraft hangar and achieved the Environmental Management Award from the Airports Council International-North America.
