Crown Zellerbach Headquarters was the first International Style curtain-wall tower to be built in San Francisco, and has claimed a position as a lasting figure in the downtown streetscape. The project includes an epoch-making open floor design and a sweeping plaza layout.
Occupying one-third of a triangular site, the building consists of a 20-story office tower and an attached service tower. The structural framework is made of rigid welded steel trusses with a 63-foot-wide span and steel decking supported on purlins. The structure cantilevers 11 feet beyond the centerline of the columns at both ends. An 8-foot-thick reinforced concrete foundation slab on grade, located approximately 45 feet below street level, distributes the column load over its entire surface. Inside, each floor has a gross area of about 15,000 square feet, unobstructed by columns.
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