High Desert Health and Rec at Northern Arizona University

Goals

The main campus of Northern Arizona University (NAU) sits in picturesque Flagstaff, situated in the mountainous Colorado Plateau. The surrounding San Francisco peaks, ponderosa pines, and four seasons weather make it an ideal setting for NAU’s community, and with all that natural beauty, it’s hard to not take special care to protect the environment. And that’s exactly what NAU has done.

In 2007, university president John Haeger pledged that NAU’s campus would be carbon neutral by 2020. The plan extends to all aspects of university life, but it most directly applies to the construction of new campus facilities. NAU has been building to LEED standards since 2003, but the 2020 action plan puts forth a much more rigorous challenge for further campus development. “It’s an enormous challenge to build 100 percent carbon-neutral buildings,” says Agnes Drogi, NAU’s director of planning, design, and construction, who adds that the 2020 plan only mandates the goal—it doesn’t specify exactly how to achieve it. “There’s no specific language for how we have to build new buildings. It leaves us the freedom to reach carbon neutrality in very innovative ways.”

Plans

The NAU planning, design, and construction team put its freedom to good use with its brand new Health & Learning Center (HLC), which opened to the NAU community in fall 2011. They brought on Cannon Design early in the project to help plan and construct the building. Initially, NAU wanted to only upgrade its previous recreation center. The old building dated back to 1989 and, at 40,000 square feet, could not serve today’s campus population. However, once NAU and Cannon began exploring options, the HLC’s ambitions rapidly expanded. “We quickly discovered that the health center needed a new building, too,” she says. “Health and sports activities go well together, so we put the two programs together.” Pushing the programmatic boundaries even further, they decided to incorporate athletic training and competition facilities, disability resources, and general classrooms into the HLC’s plans as well. Size wasn’t too much of a concern, but performance absolutely was. The entire complex would have to adhere to the campus-wide 2020 carbon-neutrality plan.

The Health and Learning Center has 3,240 evacuated solar tubes in its thermal system, which is so efficient that hot water accounts for only six percent of energy use.

Credits

NAU and Cannon immediately began working on how to balance the HLC’s programmatic needs with its sustainability goals. The architecture team knew a sprawling footprint would be necessary to comfortably integrate the five distinct programs, but key challenges arose in the attempt to achieve LEED Gold certification due to the city’s elevation and climate.

“The building sits 7,000 feet above sea level, and Flagstaff also is only second to Anchorage, Alaska, when it comes to the freeze/thaw cycles of US cities of similar or larger size—we have about 200 a year,” says Paul Dufek, senior project manager with NAU Facility Services. “The LEED credits are designed for buildings at much lower elevations. Since LEED criteria do not allow us to differentiate requirements due to elevation, it’s often quite challenging to incorporate specific credits due to our natural environment.”

The Cannon and NAU design team ultimately mitigated the elevation and climate by prioritizing efficient materials and building-operations systems. The HLC is 272,000 square feet spread over two floors and incorporates the original 40,000-square-foot recreation center. It includes 34,000 square feet of athletic facilities, 58,000 square feet of health-related spaces, 72,000 square feet for classrooms, and a 108,000-square-foot recreation center. Structurally, a steel frame supports the building’s long gym, and cast-in-place concrete composes the rest of the facility’s frame. “This structure and construction typology permits the utilization of a significantly higher recycled content percentile,” says Mark Piatt, one of the Cannon architects on the project. High-albedo roofing, efficient steel panels and glazings, and a sophisticated system of skylights and window walls also help cut both the building’s energy consumption and excess heat output.

Systems

The design move that saved the most energy involved the building’s thermal energy water-heating system. Instead of taking the power from a traditional grid, it harnesses the energy generated by the sun. “It’s a solar thermal system with 3,240 evacuated tube solar collectors,” Piatt says. “It heats 70 percent of the hot water for the building, and because it’s so efficient, the hot water system only accounts for six percent of the building’s total energy usage.”

All these numbers are tracked through the building automated system (BAS), an overarching monitoring system that tracks all the HLC’s mechanical systems and consistently reports their performance. “We can actually track and log exactly how each system is performing, and if anything goes outside of its set parameters, we can immediately analyze the situation and make adjustments,” Dufek says of the BAS. This goes a long way in ensuring that the building meets its lofty energy-efficient target.

And so far, so good. The HLC has already reduced its carbon footprint by 50 percent, and thanks to its smart design, the university is marching steadily toward that 2020 carbon neutral goal.