Excavation for the building started in June 1913. The cofferdam around the foundation was initially reinforced with timber cross-bracing until the steel frame underground had been sufficiently completed to support the cofferdam. During excavation, a cannonball from British colonial times was excavated from the site of the Equitable Building. By January 1914, crews had excavated the foundation and dug to the bedrock below street level. The steel work was built to the second floor using six derricks; the steel frame above that point was erected using lighter derricks with longer masts and booms. There were some accidents during construction, including two incidents in which workers were killed. One worker died after a crane fell on the Broadway side of the building, while another died when a crane dropped a girder onto a platform where six men were working.