During construction of Florida Polytechnic University's $60-million Innovation Science and Technology Building—which more closely resembles a flying saucer than a citadel of learning—the flappable wings ruled. Santiago Calatrava, the designer of the iconic building and its sun-tracking shading system, challenged the building team to remain unflappable while wrestling with the 300,000-sq-ft job's operable rooftop louvers and other complex features, all the time maintaining quality, schedule and budget.
The two-story elliptical-in-plan building is the signature architectural element of the new 171-acre campus for Polytechnic, itself formed in 2012 as Florida's only public university devoted to science, technology, engineering and math. The reinforced concrete structure—which supports 162,000 sq ft of research and teaching laboratories, classrooms, offices, study and support areas, common areas and an amphitheater—is surrounded by a system of 84 connected pergolas that screen the terraces.
The rooftop's operable louvers cover or shade a 250-ft-long central skylight. Thanks to a hydraulic system, each aluminum arm, as long as 62 ft, automatically raises and lowers individually with the passing sun to control solar heat gain and daylight. Louvers were designed to accommodate photovoltaic tape for future electricity generation.
Coordinate geometry, exposed concrete and steel structure, kinetic elements and a level of construction sophistication unknown in the area, coupled with a requirement to use local vendors, put the building team on the defensive even before the start of construction in November 2011. All the while, the building team felt pressure to satisfy Calatrava, who had voiced concerns about the poor level of craftwork he thought was typical of U.S. subcontractors.
To assuage the architect's fears, each subcontractor selected was put on notice that quality expectations were unusually high. Building information modeling helped with visualization, tight tolerances and coordination.
For success, general contractor Skanska USA Building Inc.'s strategy was to team smaller, local subcontractors with larger subs known to Skanska. Ultimately, 65% of the work force was from the area. The planning and other measures resulted in a project that was completed on time and on budget last June.
The wings top the list of design and construction challenges. Though the most dramatic architectural element, they were not completely designed at the start of construction. That made things more difficult because the louvers influenced each stage of the work, from foundations to final painting, according to Skanska.
A performance design, which was only a conceptual description, was all the team had to work from initially. "Everyone understood choices regarding the louvers had broad project implications," says Skanska. "Decisions were made carefully during the building's entire construction phase to reflect this fact."
The path forward regarding louver design was a series of charrettes over two years, which typified Skanska's teamwork approach to the project. Originally, the architect had proposed the wings as a pair of matched structural-steel elements, each with 47 arms. Each wing would move as a unit via hydraulic equipment at each end.
The approach proved unfeasible because the system would have generated extreme loads on the structure. As a consequence of the design collaboration, attended by structural engineer Thornton Tomasetti and steel fabricator-erector MG McGrath among others, the louvers became aluminum to reduce weight on the structure below and to minimize maintenance. Also, the original concept for each wing flapping as a whole became a system of independently moving louvers, thanks to an individual hydraulic cylinder at each louver's base, designed by Atlantic Industrial Technologies with support from McGrath.
