Down By The Riverside

Every summer, the annual Citysol arts festival counters New York's steamy streets with a green initiative. The think tank Solar One organizes this four-day event, which takes place at Stuyvesant Cove park and features lectures and design exhibits, plus organic food and live music for levity. For the past three years, the heart of the festivities has been a pavilion designed and built by Situ Studio.

Solar Pavilion 3 evolved from the two prior versions. The first was constructed from cardboard tubes. For the next one, Situ Studio used interlocking panels of CNC-milled plywood. Incorporating digital fabrication upped the flexibility quotient and did away with bolts and power tools. "But the structure was still heavy," partner Wes Rozen says. "We realized we could build a larger one with less material."

This time, Situ Studio employed slender slotted strips, 2,500 of them milled from 100 sheets of plywood certified by the Forest Stewardship Council—that's 100 sheets less than it took for the previous pavilion. The strips, each 8 feet long by either 2 or 3 inches wide, were woven together, bird's-nest fashion, and joined by I-shape aluminum fasteners. CNC-cut triangles of blue, yellow, red, or white biodegradable PVC, secured by plastic ties, added structural stiffness and shelter from the sun or rain.

A team of eight spent two weeks preassembling elements such as the 8-foot-tall wall sections and the 24-foot-long roof. That stage finished, a truck transported the pieces to the riverfront park for the three-day assembly process. "The walls stand in tripod formation, with struts pushing them apart," Rozen explains. "The roof was laid sideways on the ground, with a cable stretched between the two ends, making it arch like a bow." Pure muscle power lifted the roof into place. To hold it there, the team climbed ladders to weave in additional plywood strips for reinforcement.

Because the team included five volunteers in addition to Situ Studio staff, the final product had an ad hoc quality. "We provide a kit of parts, but how things actually come together is always a surprise," Rozen notes. One especially good surprise this year: zero materials sent to the landfill.

Left, from top: Illumination inside Solar Pavilion 3, constructed for the Citysol festival, came from LEDs inside lamps made from broken bottle glass. The aluminum connectors, custom-cut by water jet, were produced in strips 8 feet long. A table saw was then used to cut individual connectors. CNC cutting for the PVC panels took place at the Brooklyn Navy Yard. Wall sections were preassembled at the studio. Plastic ties secured the PVC. A 13-person team of staff and volunteers installed the framework on-site. Right: A month before the actual installation, the designers built a partial mock-up in the shadow of the Manhattan Bridge.

Clockwise from top left: The 4,000-square-foot, 15-foot-high pavilion encompassed 2,500 slotted strips of Forest Stewardship Council–certified plywood. A description of the design concept and process appeared on PVC banners. Four different colors of PVC were used for the panels. The plywood strips measured 8 feet long and 2 or 3 inches wide. The pavilion stretched from a Franklin D. Roosevelt Drive access road to the East River.