The superstructure was constructed from May 1956, with the first major steel column being installed at the beginning of June 1956. Seven hundred workers fitted over 5,000 individual pieces of steelwork together, which weighed in aggregate of . Because of a no-standing rule implemented in Midtown Manhattan at the time, some truckers were ticketed while delivering steel beams to the work site, prompting them to temporarily go on strike until the rule was modified. The construction of the steelwork involved bolting steel beams, rather than riveting them, to reduce noise; this work received an official "Quiet City Award" from the city. During construction, Lambert convinced the builders to carry through Mies's original design without significant change, including minor details such as the brick bonding, which was hidden from view. The superstructure was topped out during December 1956. The building's bronze and glass facade was installed starting in September 1956, and the facade work was completed in April 1957.