Stairs Play a Vital Role at the Biodesign Institute at Arizona State University

With staircases taking center stage in retail spaces like the Apple flagship store in San Francisco and in offices such as Dodge & Cox, architects are striving to elevate the utilitarian step to an architectural focal point. Employers are catching on to the trend, as well, and stairs, with their leisurely landings and central locations, are increasingly being integrated into corporate and technical spaces with the hopes of providing employees with settings ripe for spontaneous collaboration.

Epitomizing this design trend is the Biodesign Institute at Arizona State University, Building A, which, with its expansive atrium, was planned with flexibility and collaboration in mind. Tying together four levels of the Institute is a steel-supported staircase—more than a mere means of transportation, this monumental set of stairs shines as the centerpiece of the large, grand atrium. DPR built the 172,000-sq.-ft facility as part of a joint venture with Sundt Construction, Inc., working closely with architects Gould Evans Associates and Lord Aeck Sargent Architecture to manage the steel-and-tempered-glass staircase’s constructability.

“Following approval of the shop drawings, there was a constructability process. The architect created the vision, and we needed to make it a reality. So we pulled together the architect, structural engineer and trades people, there were nine of us in total, into constructability coordination meetings to discuss building this one complex element,” explained DPR’s Peter Berg.

In addition to mapping out the feasibility of the staircase, the team decided to prefabricate as much of the stairwell as possible off-site for better quality. As a result, they needed to survey all of the existing elevations and construction in place for tolerances. This detailed information was then relayed to the steel fabricator, who was responsible for building the steel accurately in the space provided and faced the task of creating the parabolas required on each landing, a very unique feature of the staircase.

“Each parabola was shaped by precisely bending a 12-foot long, 14-inch deep steel beam into five segments. None of the core team—including the steel fabricator—had ever done this before, but by involving the architect and making several trips to the fabricator to view each stage of the parabolic landing, we were successful,” said Berg.

Managing the codes and regulations associated with stairs proved equally important to the success of the project—one of the unique architectural features of the stairs was the use of separately fabricated, pre-cast, acid-etched concrete treads, which had to fit to the steel.

“There are a lot of codes we needed to comply with pertaining to the height and depth of the treads. Slopes of the stringers were precise—level and straight and according to the Uniformed Building Code. If the stair was off by two inches, the distance between each tread would be wrong,” explained Berg. “We made sure the treads were laid perfectly and met all the necessary codes.”