The new California Academy of Sciences building features a contoured, vegetated roof bordered by a cantilevered steel canopy of glazed panels that include more than 55,000 photovoltaic cells. The cells are designed to generate approximately 5 percent of the building’s electricity needs.

Under One Green Roof

emy of Sciences’ new home, which is being referred to as the greenest museum in the world because of its undulating, 2.5 acre (1 ha) vegetated roof and a variety of other environmentally benign features, began with a few sweeping sketches made in green ink. The artist was Renzo Piano, the Pritzker Architecture Prize–winning founder of Renzo Piano Building Workshop, s.r.l., based in Paris and Genoa, Italy. The year was 1999, and
Locating all of tion’s large tanks. Some of the tanks those venues within a single structure were integrated with the building’s constituted “almost a literal depiction ground-level structure and thus will of what the academy is,” notes Young. experience seismic-induced forces, “The academy is the only institution in Chambers says. The various footings the world that houses what it does— for the foundation range in thickness an aquarium and a planetarium and a from 1.5 to 4 ft (0.5 to 1.2 m). natural history museum and a scientific Although the building code in research institution, with its collection San Francisco required the use of and storage—all under one roof.” ground anchors to protect structures At the same time, the new strucof the type making up the academy’s ture also provides the academy with new home during seismic events, more usable square footage than did the previous facility while occupying a smaller footprint Arup successfully demonstrated through a nonlinear time hisin the park. It does this through the inclusion of additional tory analysis that the rocking tabletop design would perform basement areas, a more efficient configuration of the interior better during a seismic event than would an arrangement in space, and alterations to the