The 110-story Sears Tower stacks steel, glass, aluminum and concrete into the 1,454 feet (443 meters) tall private office building. It contains 4.5 million gross square feet of space.
Designed by the architectural firm of Skidmore, Owings & Merill, the Tower reaches 443 meters through a series of stepbacks at the 50th, the 66th, and the 90th floors. The base of the building, which occupies approximately one-third of a three-acre site, consists of nine 75-by-75 foot squares.

Encased in black aluminum and bronze-tinted glass, Sears Tower proudly joins the city's skyline, bringing with it a unique statistical profile:

• Construction of Sears tower took three years, and during peak times, some 1,600 people worked on the project.
  

• The Tower's framework consists of 76,000 tons of steel. The building contains enough concrete to build eight-lane highway, five miles long; has more than 16,000 bronze-tinted windows, and 28 acres of black aluminum skin.
  

• 114 rock caissons support the 222,500-ton building. Each is sunk as deep as the Statue of Liberty is tall and is securely socketed into the bedrock.
  

• The building's 103-cab elevator system divides the Tower into three separate zones - with skylobbies in between.
  

• The Tower has the life safety system devised for a high-rise building, with automatic sprinklers, smoke detectors, emergency diesel generators and a sophisticated communications system.
  

• Six automatic window-washing machines clean the building exterior eight times a year.
  

• Sears Tower has a planned population of 16,500 persons, including 7,000 Sears, Roebuck and Co. national headquarters employees. Sears occupies basically the lower 50 floors of the building; the remainder is lease to tenants.
  

• Five restaurants in the building include a delicatessen, a coffee shop, an elegant multiroom restaurant, a pub and a 1,500-seat cafeteria. Other facilities from Lower Level II to the Mezzanine level include a bank a broad variety of retail shops and services.