Chicagoans watched in amazement as the tower rose eight stories each month. Creeper cranes lifted the Christmas trees and other construction materials. Workers welded and pounded pieces into place. As the tower neared completion, workers began adding fireproofing to the outside walls of the lower floors. Then they hung the tinted glass in sections. Before the upper floors were even enclosed, workers were installing cabinets and carpets on the lower floors.
In spring 1973, workers finished framing the top floor. On May 3, the last beam was ready to be lifted more than 1,400 feet (427 m) into the air. At a special ceremony, Chicago mayor Richard J. Daley and thousands of Sears employees signed the beam. Workers lifted the beam and bolted it into place. Workers still had to add exterior walls to the top floors. They also had to finish the interior and landscape the area around the tower’s base. But major construction on the Sears Tower was complete.