Willis Tower
Adapted from Wikipedia · Discoverer experience
The Willis Tower, once called the Sears Tower, is a very tall building in the Loop of Chicago, Illinois. It has 110 stories and is 1,451 feet high. When it opened in 1973, it was the tallest building in the world, a title it kept for almost 25 years. Today, it is the third-tallest building in the Western Hemisphere and the 26th-tallest in the world.
Each year, over 1.7 million people visit the Skydeck, the highest observation deck in the United States, making it one of Chicago’s most popular places to see. Because of its great height and special location, the tower can be seen from far away. It has been featured in many movies and TV shows set in Chicago.
The building was designed by architect Bruce Graham and engineer Fazlur Rahman Khan of Skidmore, Owings & Merrill. It looks like nine squares grouped together, with seven of them stepping back at the top floors. The outside of the building is made of shiny aluminum and dark glass. The bottom part of the tower used to hold the headquarters of the retail company Sears until 1994. Today, United Airlines is the biggest tenant, using space across 16 floors.
History
Planning
Sears, Roebuck & Co. had offices in Chicago since 1906, but by 1966, they needed bigger space. Sears decided to build a new headquarters in Chicago’s Loop area instead of the suburbs. They chose a central location bounded by Franklin Street, Jackson Boulevard, Wacker Drive, and Adams Street. After some challenges in buying the land, Sears closed a block of Quincy Street to make room for the building.
Design process
Sears wanted a building with about 4.2 million square feet of space. They hired the architecture firm Skidmore, Owings & Merrill to design it. The building grew taller during planning to meet space needs. The final design, by architects Bruce Graham and Fazlur Rahman Khan, included a distinctive shape with setbacks. The tower was announced in 1970 to be 1,450 feet tall with 109 or 110 stories.
Construction
Construction began in August 1970 with foundation work. A slurry wall and caissons were built, and a sewer was rerouted. The Diesel Construction Company was the main builder. The first steel beam was placed in June 1971. Concerns arose about the tower disrupting TV broadcasts, leading to lawsuits, but these were dismissed. Construction continued despite delays from labor strikes and weather.
The tower became Chicago’s tallest building in November 1972. It was topped out in May 1973, though some work remained. Unfortunately, several workers died during construction from accidents. The building cost about $150 million and was nearly finished by September 1973 when Sears employees began moving in.
20th century
The tower opened in September 1973 with new flashing beacons on the roof. Some TV stations moved to the tower, but others stayed elsewhere. By 1974, much of the space was rented, but Sears faced competition and economic changes, leading to vacancies in later years.
In 1984, Sears renovated the lower floors to attract visitors, adding a glass dome entrance and a shopping area. Sears planned to sell the building in 1988 and eventually moved its offices out by 1995. The building changed owners several times, facing vacancy issues and financial challenges.
21st century
In 2003, the building was sold to MetLife, and later to a group of investors. Plans for a hotel were considered but canceled. In 2009, it was renamed the Willis Tower after a new tenant. In 2015, the Blackstone Group bought it and began a major $500 million renovation in 2017, which was completed in 2022. The renovation included new elevators, updated systems, and new public spaces.
Despite these changes, the number of tenants and visitors dropped significantly after 2019 due to the COVID-19 pandemic. In 2023, the value of the building was written down by $119 million.
Architecture
The Willis Tower was designed by architect Bruce Graham and structural engineer Fazlur Rahman Khan of Skidmore, Owings and Merrill. They created the building with nine square “tubes,” arranged in a 3×3 pattern, forming a square base. The building has a lot of usable space and was built to hold many people.
The Willis Tower was the first building to use this tube design. It was both strong and cost-effective, offering more space at a lower cost per area than the Empire State Building. This design has influenced many tall buildings around the world, including the tallest building, the Burj Khalifa. In 1982, two television antennas were added, making the building even taller. Later, one antenna was made longer to improve TV signals for a local NBC station, WMAQ-TV.
The outside of the Willis Tower has columns spaced 15 feet apart and is covered with aluminum and black glass. The building also has a large plaza outside, and in recent years, a new wing was added with artwork on its facade.
The inside of the building includes a lot of steel, aluminum, and concrete. It was built to withstand strong winds. The building also has a deep basement and many safety features, like sprinklers and special systems to handle fires.
Elevators and escalators
The Willis Tower was built with many elevators, including some that could carry people on two levels at once. These elevators help move people quickly through the building. There are also escalators to help people move between certain floors.
Interior
When the building was finished, the main entrance was on Wacker Drive. There were also entrances on other streets. Below ground level, there are three basement levels with many different spaces, like a cafeteria and parking.
Today, the building has two main entrances for people who work there and another entrance for visitors to the observation deck. The lower levels of the building include a shopping and dining area called the Catalog, which has many restaurants and a large shared workspace.
Skydeck
The Willis Tower’s observation deck, called the Skydeck, opened in 1974. It is located on the 103rd floor, very high above the ground, and is a popular place for tourists. Visitors can see a lot of the area around Chicago from here. The Skydeck has been updated over the years, including the addition of glass balconies called “The Ledge,” where people can stand very close to the edge of the building safely.
Height
When it was built, the Willis Tower was the tallest building in the world. However, it wasn’t the tallest structure overall because Toronto’s CN Tower was even taller, though it isn’t considered a building by some rules. Today, the Willis Tower is the third-tallest building in the Western Hemisphere, after One World Trade Center and Central Park Tower in New York City. It is also one of the tallest freestanding structures in the Americas.
Over the years, other buildings like the Petronas Twin Towers in Kuala Lumpur, Malaysia, and Taipei 101 in Taiwan have held records for different types of height. In 2007, the Burj Khalifa in Dubai became taller than the Willis Tower in every way. Later, One World Trade Center in New York City also became taller in some measurements.
Climbing
In 1981, a man named Dan Goodwin climbed the outside of the Willis Tower using special equipment, wearing a suit that looked like Spider-Man. He did this to show that there were problems with how firefighters rescue people from tall buildings. He was stopped by the Chicago Fire Department and later had to face some legal issues.
In 1999, another climber from France named Alain Robert climbed the building using only his hands and bare feet. It was very foggy near the top, making it quite slippery.
Since 2009, the Willis Tower has hosted a race called SkyRise Chicago, where people run up the stairs to the top for charity. The money raised helps the Shirley Ryan AbilityLab.
Naming rights
Sears sold the tower in 1994 and left it by 1995, but they kept the right to name it until 2003. The new owners tried to change the name to work with CDW Corp in 2005 and the U.S. Olympic Committee in 2008, but it didn’t work out. In 2009, a big British insurance company called Willis Group Holdings rented space there and got the naming rights for free. On July 16, 2009, the building was renamed the Willis Tower. The name was supposed to last for 15 years.
Some people in Chicago weren’t happy with the new name. They remembered a famous TV phrase, “What you talkin’ ‘bout, Willis?” from a show called Diff'rent Strokes. Many still called it the Sears Tower, even after the change. Some news articles and magazines even listed it as one of the worst name changes ever. Even years later, many people in Chicago still preferred the old name.
Floor plans
| Floor | Purpose |
|---|---|
| 110 | Penthouse Roof |
| 109 | Roof with Mechanical Penthouse |
| 104–108 | Mechanical and communications |
| 103 | Skydeck Observatory |
| 100–102 | Communications |
| 99 | Secondary Skydeck and Restaurant |
| 90–98 | Offices |
| 88–89 | Mechanical |
| 68–87 | Offices |
| 66–67 | Sky lobby, restaurants |
| 64–65 | Mechanical |
| 35–63 | Offices |
| 34 | Sky lobby, conference center |
| 33 | Sky lobby, restaurant, fitness center |
| 29–32 | Mechanical |
| 3–28 | Offices |
| 2 | Upper lobby, restaurants |
| 1 | Lobby, shops and restaurants |
| LL3–LL1 | Lower lobby, Skydeck lobby, shops and restaurants |
Broadcasting
Many radio stations have transmitters at the top of the Willis Tower. They are ranked by how high they are placed, with some sharing the same antenna using special equipment. Because the tower is so tall, FM radio stations have limits on how strong their signals can be.
The NOAA Weather Radio station KWO39 sends out signals from the tower at 162.550 MHz. It is run by the National Weather Service in Chicago and can trigger alerts on special weather radios when there is dangerous weather coming.
East mast 509 m: WFLD 32, 435.5 kW, Fox Television Stations 500 m: WBBM-TV 2, 29.5 kW, CBS Television Stations 491 m: WBBM-TV 2, 31 kW, CBS Television Stations 482 m: 480 m: WSCR-FM 104.3 MHz, 4.1 kW, Audacy 476 m: WTMX 101.9 MHz, 4.2 kW, Hubbard Broadcasting 474 m: WBBM-FM 96.3 MHz, 3.3 kW, Audacy 470 m: WFMT FM 98.7 MHz, 6.0 kW, Window to the World Communications 468 m: WLS FM 94.7 MHz, 4.4 kW, Cumulus Media | West mast 520 m: WFLD 32, 1 MW, Fox Television Stations 509 m: WMAQ-TV 5, 398 kW, NBC Owned Television Stations 508 m: 498 m: WGN-TV 9, 645 kW, Tribune Broadcasting 496 m: WTTW 9, 250 kW, Window to the World Communications 473 m: WCIU-TV 26, 1 MW, Weigel Broadcasting 460 m: WFMT FM 98.7 MHz, 6.0 kW, Window to the World Communications 451 m: WFMT FM 98.7 MHz, 6.0 kW, Window to the World Communications 444 m: WKQX FM 101.1 MHz, 3.7 kW, Cumulus Media 442 m: W264BF FM 100.7 MHz, 0.006 kW, Calvary Radio Network |
Cultural depictions
The Willis Tower has been shown in many movies and TV shows set in Chicago. For example, in Ferris Bueller's Day Off, the characters visit the observation deck. In Late Night with Conan O'Brien, a fun character called The Sears Tower Dressed In Sears Clothing appeared when the show was in Chicago in 2006.
The building also appears in other films. In The Dark Knight, it is part of Gotham City. In Transformers: Dark of the Moon, many scenes take place there. And in Man of Steel, the tower is where the Daily Planet offices are located.
Position in Chicago's skyline
The Willis Tower stands very tall in Chicago's city view. It was the tallest building in the world when it opened in 1973 and kept that title for about 25 years. Today, it is the third-tallest building in the Western Hemisphere and one of the tallest buildings in the world.
Images
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