The Willis Tower, the tallest building in Chicago, has been knocked out of the Council of Tall Buildings and Urban Habitat's (CTBUH) top ten list as China's Shanghai Tower officially opened this month. Formerly known as the Sears Tower, the 108-story building designed by Bruce Graham and Fazlur Khan of Skidmore, Owings and Merrill held the title as the tallest in the world for nearly 25 years after it was completed in 1974. Standing at a height of 2,073 feet, China's Shanghai Tower has become the second tallest building in the world, trailing the 2,722-foot-tall Burj Khalifa in Dubai. However, the Willis has had some staying power as it remained one of ten tallest buildings in the world for 41 years. Cities in the Middle East and southeast Asia are building supertall towers at an incredibly fast pace, and because of this, the CTBUH predicts that the Willis will be knocked out the list of the world's 20 tallest towers within the next five years.
When incorporating the Willis Tower's antennas into its total height, the building stands at 1,729 feet — a height that would place it within the top five tallest towers in the world. However, the CTBUH, the organization that acts as the official authority on building height, does not include the Willis' antennas in its total height. Meanwhile, towers like One World Trade Center in New York, Taipei 101 in Taipei and the Petronas Towers in Kuala Lumpur all have tall ornamental spires, which are considered a part of the structure and are included in these buildings' official height. Unfortunately, it does not appear that Chicago will be returning the top ten list anytime soon. The only supertalls currently proposed at the moment are the 1,144-foot-tall Vista Tower designed by Studio Gang and the 1001-foot-tall 1000 S. Michigan Ave. designed by Helmut Jahn. However, if new rumors of a major downsizing of 1000 S. Michigan prove to be true, then Chicago will only have one (official) supertall in the pipeline.
·Shanghai Tower Has Completed, Now the Second-Tallest Building in the World [CTBUH]
·Top 20 tallest towers [CTBUH]
·Previous Willis Tower coverage [Curbed Chicago]