The structure placed on the star columns forms the technical penthouse, comprising straight trusses, curved trusses, long-span beams, shorter beams and suspended catwalks. To maximize the view of the stage, says Bingham, interior columns are situated in the standing-room area under the balcony. There are eight columns, which sit on concrete-filled drilled piers that descend 28 ft. A stiff beam assembly sits on these columns and supports the cantilevered balcony. The balcony roof is tied down with tension rods that run behind the balcony seating area.
Light comes through the truss's translucent reinforced plastic facing.
Behind the glulam is an acoustical layer, and another off-white plastic material placed in vertical slats tops the roof. The design called for rods ranging from 26 to 60 ft long, a length not produced in the U.S. Project engineers had to go to the U.K. to find a supplier, McCall Ltd., Sheffield. Engineer Chrystalla Kartambi, who took over the project for Arup in 1996 when Nordenson left the firm, worked with Nordenson to defend the decision to use the U.K. product. Kartambi and Damyu Radheshwar, Polshek's project architect, approached the Applied Building Department of New Mexico for approval of the U.K. steel. Their proposal alluded to the sole prior use in this country, in a California structure.