Teaching Tool

NAU Research Facility Demonstrates Green Building Techniques

by Scott Blair

Northern Arizona University in Flagstaff is currently constructing the $21 million Applied Research and Development facility, a 61-000-sq.-ft. collaborative research building located at one of the school's most prominent entrances. The building team will attempt to be the first to achieve a LEED platinum rating in Arizona

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From the beginning, the new Applied Research and Development facility at Northern Arizona University was conceived by the school's administration as a LEED platinum-certified building.

But the task was not easy.

"Building a LEED project at 7,000-ft. elevation is a major issue," said Mark Wilhelm, principal with Phoenix-based Green Ideas, the green building consultant on the project. "Flagstaff has more freeze/thaw cycles than just about any place in the country. No other platinum buildings have been attempted at this altitude."

Concrete can take longer to cure and glazing can perform differently due to lower atmospheric pressure, Wilhelm added.

To date there are less than two dozen LEED platinum-rated buildings in the world, only one of which also includes lab space, according to the U.S. Green Building Council's Web site.

The main tenant of the NAU building will be the Center for Sustainable Environments. The center focuses on reducing the ecological impacts of energy use, water, food production, transportation and building.

One of the major issues in the NAU project was controlling the budget in the university facility built with public funds. While going for LEED-certified (the lowest level of designation) doesn't necessarily add significant costs to a project, the project team had to examine what it would take to achieve platinum, the highest rating possible, said Robin Shambach, project architect and principal with executive architect Burns Wald-Hopkins Architects of Tucson, the firm that designed Arizona's first LEED-certified building, the Desert Vista Campus for Pima Community College in Tucson.

"There was some education on the owner as well, as to the cost implications of a platinum building and how that would influence the design and construction phases," Shambach added.

With the final budget set at $20.5 million, the firm partnered with London-based design architect Hopkins Architects and San Francisco-based Ove Arup & Partners, the mechanical, electrical and structural engineer. Phoenix-based Kitchell Contractors was selected as the construction manager-at-risk.

The three-story building includes lab space on the top floor, office space on the first and second, and meeting rooms.

The Center for Sustainable Environments regularly collaborates with several federal land agencies, which will also lease space in the new building, including the National Park Service and the U.S. Geological Survey.

While originally planned as an 80,000-sq.-ft. building, construction cost escalations resulted in a reduction in size to nearly 60,000 sq. ft. by removing two structural bays during value engineering, according to Marty Olson, project director with Kitchell.

Another preconstruction challenge was in finding materials. "One of the LEED platinum requirements is to find materials within a 500-mi. radius," Olson said.

"The closer you are able to find those materials the less travel time and fuels are expended in getting that material here."

Finding enough subcontractors in northern Arizona that were experienced in LEED was also difficult. To drum up interest in the project, Kitchell held several subcontractor fairs at NAU to solicit as much local participation as possible. Kitchell and Green Ideas provided LEED training and orientation as needed once subcontractors were selected.

To maximize the opportunity to gain additional LEED points, the building's design called for use of both structural steel and concrete.

"If you build a steel building, you are going to get a lot of points on the recycled content, but if you build a concrete building, you'll get points for local/regional content," Wilhelm said. "This building had to be a mixture of the two because we wanted all those points to achieve platinum. So it became a much more challenging design."

Construction began in June 2005 near a prominent entrance to the campus and within a city of Flagstaff detention basin. "If you look at the site plan, the first thing you notice is the large area for the detention basin, and then our building is shaped around that," Shambach said. "The orientation is very critical - it is south-southeast to gather light and allow for some solar heating."

The structural concrete provides solar massing, which helps level temperature swings throughout the day. A three-story gallery space faces the basin, fronted by a gently curving curtain wall system.

"The gallery space allows for solar gain and for light penetration, and the actual footprint of the building is long and narrow, allowing for views and daylighting as much as possible throughout the space," Shambach added.

To maximize LEED points for use of recycled content, local materials and as one of four allowed innovation credits, the cement content of the project's concrete was reduced by using 40 percent fly ash, a by-product of coal-fired power plants.

"That was a big deal," Shambach said. "It hadn't really been done before in exposed architectural concrete."

There was a possibility that using that much fly ash would create a finish that was too uneven in color or too dark. "We poured a mock-up to see what the concrete would look like for the architect and owner," Olson said. "We had to work around different vibrating techniques to mitigate air pockets that could be exposed in the concrete once the forms were stripped, but all in all it turned out very well. One of our biggest challenges turned out to be one of our biggest successes."

Other significant green building features of the project include a low-pressure under-floor ventilation system, evaporative cooling, natural ventilation and heat recovery via heat wheels and heat pipes. "The users of the building may need to participate more in their own comfort," as opposed to a typically air-conditioned building, Shambach said.

Another innovation was using pervious concrete on the parking lot instead of conventional asphalt pavement. The recently developed product is porous to allow water drainage and to reduce the heat-island effect.

"It will be the first pervious pavement in the state of Arizona," Olson said. "It's going to be an interesting product here that will be used as a teaching tool on this project."

The entire building will also perform double-duty as a teaching tool for students and the community. A meeting room will feature a planted green roof, which acts as an insulator and stormwater management system. "The upper floors look down on it and it's a great opportunity to model for the community what a green roof looks like and how it works," Shambach said.

The project inspired Phoenix-based power supplier APS to donate $1 million to help fund the project and to provide solar photovoltaic cells what will supply up to 20 percent of the power for the building.

The building will be complete in the first quarter 2007, but it will not be the last green building for the campus. "Through working with NAU, we have developed a campus-wide LEED program," said Charlie Popeck, principal with Green Ideas. "The university is committed to building to the LEED standard."

Key Players

Owner: Arizona Board of Regents
Architect: Burns Wald-Hopkins Architects; Hopkins Architects
Construction Manager: Kitchell Contractors
LEED Consultant: Green Ideas
Electrical: JFK Electrical Contracting
Mechanical: Climatec; Dial Mechanical; Boyer Metal Co.
Concrete: Kitchell Contractors
Steel: Triad Steel Services; S Diamond Steel; The Structures Group

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