Poised to become the most sustainable building on the University of Arizona campus, Environment & Natural Resources Phase 2 is a forward-focused, people-centered building whose much-anticipated debut finally has arrived.

A point of pride for the ENR2 team is the building's inspired use of the slot canyon, which illustrates how the design responds to the desert environment, said May Carr, senior architect for Planning, Design and Construction and ENR2's design manager.

"When this happens, it allows the building to tell a story that is bigger than how many offices need to be provided, for example," Carr said.

"The strength of the concept permeates many of the design decisions that get made, reinforcing the concept and reinforcing the clarity of the design," she said, adding that other UA examples include the Meinel Optical Sciences Building, which uses the camera obscura as inspiration, or the Helen S. Schaefer Building, with its garden transitioning from active to contemplative.

In its totality, the nearly 151,000-square-foot ENR2 building stands as a visual, physical and symbolic representation of the UA's commitment to constructing buildings with lower impact while encouraging interdisciplinary collaboration.

"The University has a reputation for doing great design and for producing great buildings," Carr said. "ENR2 is special because it really showcases the University and speaks to what architectural design in the Southwest can be, and in a sustainable way.

"There are so many things about ENR2 that come together in this symbol of the slot canyon," Carr said, adding that the building is meant to inspire. "The building speaks of its time and its place, and especially what good design at the University of Arizona can be."

The greenest building on campus will receive its formal introduction during a Sept. 10 dedication event, which is free and open to the public. Brief remarks will be made by UA President Ann Weaver Hart and Provost Andrew Comrie.

ENR2's design team included the Tucson-based GLHN Architects & Engineers and Richard+Bauer Architecture, the Phoenix firm that also designed the UA's Bryant Bannister Tree Ring Building and the award-winning Meinel Optical Sciences expansion.

Hensel Phelps Construction Co. was the contractor. In addition to ENR2, the company has built other UA buildings, including the Chemical Sciences Building, the Medical Research Building and the Arizona Cancer Center on the Phoenix Biomedical Campus.

Concepts for ENR2 were being penned during a time when the nation's higher-education institutions were urged to reduce campus carbon footprints. Since the last decade, the UA has greatly enhanced its sustainability initiatives with new programs, courses, degree programs and LEED-certified buildings.

ENR2 is part of that legacy, while contributing to the University's deliberate move toward expanded campus-wide sustainability efforts.

"The new ENR2 building is highly inspirational," said Peter Dourlein, the UA's assistant vice president of Planning, Design and Construction.

"It's not enough for our buildings and spaces to just facilitate — they must inspire," Dourlein said. "The building is not extravagant by any financial measure. There are simple materials, like concrete and steel, but they are used in such creative ways. The entire University and consultant team created a highly successful place that will efficiently and effectively serve and inspire the University for many years to come."

Some of ENR2's most distinguishing features include:

• A courtyard modeled after a slot canyon, which creates an exterior circulation effect, driving down internal temperatures.
• A heating and cooling system that is projected to result in a 30 percent reduction in annual energy budget.
• Waterless, dual-flush and low-flow toilets and faucets to reduce water use.
• Plentiful natural lighting and the use of vacancy sensors, which control and adjust lighting and air conditioning in individual offices.
• Low-maintenance, durable building materials, including unfinished metal "fins" that are developing a patina and provide shade to the building.
• Exposed concrete and exterior heat-absorbing masonry walls, built to last for the next 100 years.
• A water harvesting system that runs five stories, which will irrigate the building's plants with stored rainwater runoff.
• Landscape beds on each level to help with cooling.

"We wanted to ensure that as many materials as possible were doing double duty," Carr said, adding that the team employed numerous techniques and technologies meant to drive down temperatures within ENR2. "Most of the building functions like an old, adobe house. We adopted similar concepts."

Also, ENR2's roof is envisioned to become a learning laboratory that one day will include gardens to absorb heat, offer insulation and provide a mini ecosystem for birds, insects and plants.

Given the building's strong cohabitation with the natural environment, it seems fitting that a hummingbird family made ENR2 its home over the summer.

"The ENR2 building represents yet another series of great visions realized at the University of Arizona," Dourlein said.

"Senior leadership had the great wisdom to gather these earth and environmental sciences programs and world-renowned researchers to facilitate the highest-level interdisciplinary research," he said. "There is no question that these folks are leading in discovery of issues that affect our planet and our lives."

Housed within ENR2 are the Institute of the Environment, the School of Natural Resources and the Environment, the School of Geography and Development, and portions of the Department of Mathematics. 

The building's occupants agree to share space, rather than to segment office spaces. Thus, in the interest of interaction, different departments are located on different floors throughout the building.

In addition to faculty offices and graduate student hubs, ENR2 contains research and instructional laboratories; a 600-person, high-tech auditorium; a 120-person meeting space; the new Slot Canyon Café; and additional shared work spaces meant to encourage interdisciplinary connections.

"The inclusion of different people in different spaces is very important," Carr said.

For Carr, who also worked on construction and design projects at the Meinel Optical Sciences Building and the College of Architecture, Planning and Landscape Architecture, ENR2 has been something of a capstone project.

"As an architect, the best that you can get with a building is to be inspirational," said Carr, a native Tucsonan who earned her bachelor's degree in architecture from the UA in 1976.

"We want to be beyond what a spec office could be. We wanted to show people what good design and engineering could be, and use it as a benchmark for the rest of the community, the state and the region."