Willis Tower

skyscraper in Chicago, Illinois

The Willis Tower, formerly known as the Sears Tower, is a 108-story, 1,450-foot (442.1 m) skyscraper in Chicago, Illinois. The tower has 108 stories, though the building's owners count the main roof as 109 and the mechanical penthouse roof as 110.[4][5] When it finished costruction in 1974, it beat the World Trade Center in New York City to become the tallest building in the world, a title that it held for nearly 25 years. It was also the tallest building in the Western Hemisphere for 41 years, until the new One World Trade Center beat it in 2013.

Willis Tower
Sears Tower ss.jpg
The Willis Tower, then known as the Sears Tower, in 1998
Willis Tower is located in Chicago metropolitan area
Willis Tower
Willis Tower
Location in Chicago
Willis Tower is located in Illinois
Willis Tower
Willis Tower
Location in Illinois
Willis Tower is located in the United States
Willis Tower
Willis Tower
Location in the United States
Former namesSears Tower (1973–2009)
Record height
Tallest in the world from 1973 to 1998[I]
Preceded byWorld Trade Center (1970)
Surpassed byPetronas Twin Towers
General information
TypeOffice, observation, communication
Architectural styleInternational
Location233 S. Wacker Drive
Chicago, Illinois 60606
United States
Coordinates41°52′44″N 87°38′09″W / 41.8789°N 87.6358°W / 41.8789; -87.6358Coordinates: 41°52′44″N 87°38′09″W / 41.8789°N 87.6358°W / 41.8789; -87.6358
Current tenantsUnited Airlines
Named forWillis Group Sears (1973–2009)
Construction started1970; 51 years ago (1970)
Completed1973; 48 years ago (1973)
OwnerBlackstone Group[1]
Architectural442.1 m (1,450 ft)[2]
Tip527 m (1,729 ft)[2]
Top floor412.7 m (1,354 ft)[2]
Technical details
Floor count108[3] (+3 basement floors), 110 floors including mechanical.
Floor area416,000 m2 (4,477,800 sq ft)[2]
Lifts/elevators104,[2] with 16 double-decker elevators, made by Westinghouse, modernized by Schindler Group
Design and construction
ArchitectSkidmore, Owings and Merrill[2]
Fazlur Rahman Khan
Bruce Graham
Main contractorMorse Diesel International
I. ^ Willis Tower at Emporis

Willis Tower is seen as the best work of architect Fazlur Khan.[6] It is the third-tallest building in the United States and the Western hemisphere. It is also the 23rd-tallest in the world. Each year, more than one million people visit its observation deck, the highest in the United States, making it one of Chicago's most popular tourist places. The tower was renamed in 2009 after the Willis Group bought the tower.

As of April 2018, the building's largest office partner is United Airlines, which moved its corporate headquarters from 77 West Wacker Drive in 2012.[7][8][9] Other major company offices in the tower include Schiff Hardin and Seyfarth Shaw.[9] Morgan Stanley moved into the tower in 2019.[9]

It was known as the Sears Tower until 2009, as it was the headquarters of retail company Sears from its opening in 1974. Many people from Chicago still call the tower by its original name.[10]


Planning and constructionEdit

In 1969, Sears, Roebuck & Co. was the largest retailer in the world, with about 350,000 employees.[11] Sears wanted to put many of its employees into one building on the western part of Chicago's Loop.[11] The company was given two locations for the proposed tower: the Goose Island area northwest of downtown and a two-block area by West Chicago Loop not far from Grant Park.[11][12] Sears eventually bought the West Chicago loop location and bought 15 old buildings from 100 owners and paid $2.7 million to the city.[12][13]

The tower during its construction, 1973

Sears, needed 3 million square feet (280,000 m2) of office space for its planned tower, hired architects Skidmore, Owings & Merrill (SOM).[14] Architects Bruce Graham and Fazlur Khan designed the building.[14] They designed it as a nine square "tubes".[15] It was connected in a 3×3 metal wrap forming a square base with 225-foot (69 m) sides.[15] All nine tubes would rise up to the 50th floor of the building, where the northwest and southeast tubes end.[16] The northeast and southwest tubes reach the 66th floor with the north, east, and south tubes end at the 90th.[16] The last west and center tubes reach 108 floors.[12] The Sears Tower was the first building to use this design.[17] It was both cheaper and stronger: at 1,450 feet, it gave more space and rose higher than the Empire State Building and cost much less per unit area.[17] The system would become successful in skyscraper construction and has been used in most supertall buildings.[18][19]

With the floors left over Sears decided to give them to other companies for office room.[20] Small metal floors were added to give enough space to people working in the tower.[16] Skidmore architects proposed a tower with large, 55,000-square-foot (5,100 m2) floors in the lower part of the building.[16] They also added metal floors with many setbacks, which would give the tower its well known look.[16]

The tower passed the height of New York's unfinished World Trade Center to become the world's tallest building.[21] The height was limited by the Federal Aviation Administration (FAA) to protect air traffic.[22] The financing of the tower was paid by Sears.[23] It was topped with two antennas for television and radio broadcasting.[24] Sears and the City of Chicago approved the design and the first steel was put in place in April 1971.[25] The building was completed in May 1973.[25] The construction cost about US$150 million.[26]

Black bands appear on the tower around the 29th–32nd, 64th–65th, 88th–89th, and 104th–108th floors.[27] These give the building's environmental support systems and hide its belted trusses.[27] Even though adding a fire sprinkler system was not forced, the building was built with one from the beginning.[28] There are around 40,000 sprinkler heads in the building, at a cost of $4 million.[29]

In February 1982, two television antennas were added to the building, increasing its total height to 1,707 feet (520.3 m).[24] The western antenna was made bigger, bringing the overall height to 1,729 feet (527 m) on June 5, 2000.[2] It was done to improve reception of local NBC station WMAQ-TV.[24]

Legal actionEdit

As the construction of the building reached as the 50th floor in 1972, unsuccessful lawsuits were filed wanting to stop the building from passing 67 floors.[30] The suits said that above that point television signal would become worse and cause property values to fall.[31]

The Illinois Citizens' Committee for Broadcasting wanted the Federal Communications Commission (FCC) to stop its construction so the building would not ruin the television reception.[32] On May 26, 1972, the Commission rejected to take action as they did not have the power to do anything.[32] On June 30, 1972, the Illinois Supreme Court supported their rulings.[32] On September 8, 1972, the United States Court of Appeals for the Seventh Circuit supported the FCC decision, ending the lawsuit.[32]

After openingEdit

Sears' did not have any company growth because of the success of their rivals Kmart, Kohl's, and Walmart.[33] As a result, there was an increase of office space in the 1980s.[33] The tower did have as much companies buying office spaces and was half-empty for ten years.[33][34]

The tower seen from Lake Michigan

In 1984, Sears decided to improve the appearance of the lower floors of the tower to pedestrians.[35] Their solution was the creation of a new entrance known as "Lunchbox Entrance".[35] Sears looked into selling the Sears Tower in the late 1980s.[34] In July 1990, with no possible buyers, Sears took out a mortgage loan on the tower for $850 million from MetLife and AEW Capital Management.[36] Sears talked about the loan again in 1994.[36] The negotiations led to an agreement where Sears would no longer be responsible for the $850 million loan, although it would only own the name of the building.[36] As part of the 1994 agreement, AEW and Metlife would be able to take official ownership of the building in 2003.[37]

In 1990, the law firm of Keck, Mahin & Cate decided to move into a development that would become 77 West Wacker Drive, moving away from the tower.[38] Just two years later, Sears began a move of its own offices out of the building to a new campus in Hoffman Estates, Illinois.[37]

The tower seen from the Chicago River

However, in 1997, Toronto-based TrizecHahn, at the time the lessee of the CN Tower, bought AEW's holdings in the building for $110 million.[39][40] After the September 11 attacks, two of the largest office partners, Goldman Sachs and Merrill Lynch, quickly announced plans leave the building's 300,000 ft2 space.[41] In 2003, Trizec sold its holdings of the tower to MetLife for $9 million.[42]

In 2004, MetLife sold the building to a group of investors from New York City and Skokie, Illinois.[43] The price was $840 million, with $825 million held in a mortgage.[44]

In June 2006, seven men were arrested by the FBI and charged with plans to destroy the tower.[45][46] The case went to court in October 2007.[47] After three trials, five of the suspects were convicted and two acquitted.[48] The leader of the group, Narseal Batiste, was sentenced to 13.5 years in prison.[49] In response to the possible threat of an attack, the building's largest company space at this time, Ernst & Young, moved to North Wacker Drive in early 2009.[50]

Since 2007, the owners had thought about plans for the construction of a hotel on the north side of the building.[51] The second building was considered in the original design.[51] The plan was eventually cancelled as the city did not allow the construction of a tall building in that location.[51]

In February 2009, the owners announced they were thinking of a plan to paint the building silver, an idea that was later stopped.[52] It was hoped that a new, silver, paint-job would "rebrand" the building and show its energy efficiency for a cost of $50 million.[52]

In 2015, the Blackstone Group bought the tower for a reported $1.3 billion, the highest price ever paid for a U.S. property outside of New York City.[53] In 2017, Blackstone announced a $500 million renovation for the property which would include the construction of a six-story commercial area in the tower's plaza area.[54]

Naming rightsEdit

The tower's entrance

Although Sears' naming rights ended in 2003, the building was continued to be called the Sears Tower for many years, despite multiple changes in ownership.[36] In March 2009, London-based insurance broker Willis Group Holdings agreed to lease a part of the building and got the naming rights.[55] On July 16, 2009, the building was officially renamed Willis Tower.[56] On August 13, 2012, United Airlines announced it would move its corporate headquarters from 77 West Wacker Drive to Willis Tower.[7]

The naming rights are valid for 15 years, so it is possible that the building's name could change again as soon as 2024.[57] Many Chicagoans still call the tower by its old name, with many saying its tradition to do so.[58] In a July 2009 CNN article, it showed some Chicagoans unable to accept the Willis Tower name.[59] In an article that appeared in the October 2010 issue of Chicago magazine that ranked the building among Chicago's 40 most important, the author refused call it the "Willis Tower".[60] Time magazine called the name change one of the top 10 worst corporate name changes.[61]


On May 25, 1981, Dan Goodwin, wearing a homemade Spider-Man suit while using suction cups and sky hooks.[62] Even though the Chicago Fire Department tried to stop him, he made the first successful outside climb of the tower.[62] Goodwin was arrested at the top after the seven-hour climb and was later charged with trespassing.[63][64]

In August 1999, French urban climber Alain "Spiderman" Robert, using only his bare hands and feet, climbed the building's outside glass and steel wall all the way to the top.[65] He climbed at the last 20 stories of the building.[65]

Since 2009, the Willis Tower has hosted SkyRise Chicago, the world's tallest indoor stair climb as a charity event.[66] Participants can legally climb the Willis Tower's 103-story staircase.[66]

Details and heightEdit

The structure's design

Skidmore architects designed Willis Tower to have large floors of 55,000 square feet (5,100 square meters) in the lower part of the building.[14] They got the idea for the design from an advertisement for a package of cigarettes.[67]

From the ground to the top of the taller antenna, Willis Tower is 1,729 feet (527 meters) tall.[14][67] It leans about 4 inches (10 centimeters) towards the west because of the unequal loads on its foundation.[68] The observatory elevators in the tower are the fastest in the world at 1,600 feet (490 meters) per minute.[69] With clear weather, four states can be seen from the observation deck: Michigan, Indiana, Illinois, and Wisconsin.[70]

The Willis Tower remains the third tallest building in the Americas (after One World Trade Center and Central Park Tower) and the Western Hemisphere.[71] With a height of 1,729 feet (527 m) with its antenna, it is the third-tallest freestanding structure in the Americas and eighth-tallest freestanding structure in the world.[72]

On November 8, 2013, architects in Chicago and New York City started talking about the height of the One World Trade Center.[73] They were saying that Willis Tower might be taller.[73] On November 12, it was confirmed that One World Trade Center is taller than the Willis Tower.[74]

At the bottom, the lowest level of Willis Tower is 43 feet below the elevation of Franklin St.[75] Many broadcast station transmitters are located at the top of Willis Tower.[24]

The SkydeckEdit

The tower's glass ledge on its skydeck

The Willis Tower observation deck, called the Skydeck, opened on June 22, 1974.[72] It is located on the 103rd floor with an elevation of 1,353 feet (412.4 m).[72] It is the highest observation deck in the United States and one of Chicago's most famous tourist attractions.[72][76] Elevators reach the top in about 60 seconds, allowing people to feel the change in pressure as they go up.[69] The Skydeck competes with the John Hancock Center's observation floor a mile and a half away but reaching 323 feet (98.5 m) lower.[72] Some 1.7 million tourists visit annually.[72] A second observation deck on the 99th floor serves as a backup and for private events.[77] The tourist entrance can be found on the south side of the building along Jackson Boulevard.[78]

In January 2009, a major renovation of the Skydeck began, including the addition of glass balconies which extend about 4 feet (1.2 m) outside from the building.[79] The all-glass boxes, known as "The Ledge", allow visitors to see the street below.[79] The boxes, which can hold 5 short tons (4.5 metric tons).[79] It opened to the public on July 2, 2009.[79] On May 29, 2014, the laminated glass flooring of one of the boxes broke while visitors were inside but there were no injuries.[80] The flooring on that same box shattered on June 12, 2019.[81]


The tower has been given ENERGY STAR certification by the U.S. Environmental Protection Agency (EPA) in 2018.[82] This is for being one of the best buildings of its type in the United States for energy efficiency.[82]

Related pagesEdit


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