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Willis Tower
Sears Tower
Building
Completed
1974
Office
All-Steel
LEED Recertification Platinum (2019), LEED Gold O+M: Existing Buildings (2016)
442.1 m / 1,451 ft
108
3
104
8.1 m/s
423,638 m² / 4,560,001 ft²
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You must be a CVU Member to view this resource.
Construction Start
Completed
Retrofit Start
Retrofit End
Usually involved in the front end design, with a "typical" condition being that of a leadership role through either Schematic Design or Design Development, and then a monitoring role through the CD and CA phases.
The Design Engineer is usually involved in the front end design, typically taking the leadership role in the Schematic Design and Design Development, and then a monitoring role through the CD and CA phases.
The Design Engineer is usually involved in the front end design, typically taking the leadership role in the Schematic Design and Design Development, and then a monitoring role through the CD and CA phases.
Other Consultant refers to other organizations which provided significant consultation services for a building project (e.g. wind consultants, environmental consultants, fire and life safety consultants, etc).
These are firms that consult on the design of a building's façade. May often be referred to as "Cladding," "Envelope," "Exterior Wall," or "Curtain Wall" Consultant, however, for consistency CTBUH uses the term "Façade Consultant" exclusively.
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Usually involved in the front end design, with a "typical" condition being that of a leadership role through either Schematic Design or Design Development, and then a monitoring role through the CD and CA phases.
The Design Engineer is usually involved in the front end design, typically taking the leadership role in the Schematic Design and Design Development, and then a monitoring role through the CD and CA phases.
The Engineer of Record takes the balance of the engineering effort not executed by the “Design Engineer,” typically responsible for construction documents, conforming to local codes, etc.
The main contractor is the supervisory contractor of all construction work on a project, management of sub-contractors and vendors, etc. May be referred to as "Construction Manager," however, for consistency CTBUH uses the term "Main Contractor" exclusively.
Other Consultant refers to other organizations which provided significant consultation services for a building project (e.g. wind consultants, environmental consultants, fire and life safety consultants, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
You must be a CVU Member to view this resource.
Usually involved in the front end design, with a "typical" condition being that of a leadership role through either Schematic Design or Design Development, and then a monitoring role through the CD and CA phases.
The Design Engineer is usually involved in the front end design, typically taking the leadership role in the Schematic Design and Design Development, and then a monitoring role through the CD and CA phases.
The Design Engineer is usually involved in the front end design, typically taking the leadership role in the Schematic Design and Design Development, and then a monitoring role through the CD and CA phases.
The main contractor is the supervisory contractor of all construction work on a project, management of sub-contractors and vendors, etc. May be referred to as "Construction Manager," however, for consistency CTBUH uses the term "Main Contractor" exclusively.
Other Consultant refers to other organizations which provided significant consultation services for a building project (e.g. wind consultants, environmental consultants, fire and life safety consultants, etc).
These are firms that consult on the design of a building's façade. May often be referred to as "Cladding," "Envelope," "Exterior Wall," or "Curtain Wall" Consultant, however, for consistency CTBUH uses the term "Façade Consultant" exclusively.
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Usually involved in the front end design, with a "typical" condition being that of a leadership role through either Schematic Design or Design Development, and then a monitoring role through the CD and CA phases.
The Design Engineer is usually involved in the front end design, typically taking the leadership role in the Schematic Design and Design Development, and then a monitoring role through the CD and CA phases.
The Engineer of Record takes the balance of the engineering effort not executed by the “Design Engineer,” typically responsible for construction documents, conforming to local codes, etc.
The CTBUH lists a project manager when a specific firm has been commissioned to oversee this aspect of a tall building’s design/construction. When the project management efforts are handled by the developer, main contract, or architect, this field will be omitted.
The main contractor is the supervisory contractor of all construction work on a project, management of sub-contractors and vendors, etc. May be referred to as "Construction Manager," however, for consistency CTBUH uses the term "Main Contractor" exclusively.
Other Consultant refers to other organizations which provided significant consultation services for a building project (e.g. wind consultants, environmental consultants, fire and life safety consultants, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
26 September 2023
ABC7 Chicago successfully installed a brand new antenna on the Willis Tower on a Sunday morning. The process was captured by Chopper 7. A helicopter...
The Willis Tower (formerly Sears Tower) in Chicago, with its signature black aluminum and bronze-tinted glare-reducing glass, was the tallest building in the world for nearly 25 years. Completed in 1974, Willis Tower set the standard for supertall skyscrapers around the globe, both in its innovative design and graceful styling. With approximately 424,000 square meters of gross floor area, the building is comparatively large for its height, with its foundation and the first 50 floors taking up an entire city block before the building begins to narrow.
The step-back design of the structure was designed by the architects as a direct result of Sears’ space requirements. The designers were required to develop a building that incorporated not only very large office floors, which were necessary to Sears’ operation, but also a variety of smaller floors which would be more suitable for tenants requiring less floor area. These requirements resulted in a bundled tube structure, the first of its kind. This innovative design was not only structurally efficient, but it also managed to be economical as well. It has proven to be a remarkably influential design typology, and has been used in most supertall buildings built since the Willis Tower, including the Burj Khalifa.
An assortment of features has kept the tower active, inviting, and efficient over its operational life. An undulating Alexander Calder sculpture greets office workers in the west lobby. Meanwhile, a 2009 addition to the observation deck affords visitors with vertigo-inducing views of Chicago via “The Ledge,” a series of boxes with transparent floors that extrude from the top of the building. Although the Willis Tower was built in an age before sustainable design matured, the building’s owners have recently implemented several sustainable elements, including low-flow fixtures that conserve more than 38 million liters of water annually, and high-efficiency lighting systems that help curb electrical loads.
26 September 2023
ABC7 Chicago successfully installed a brand new antenna on the Willis Tower on a Sunday morning. The process was captured by Chopper 7. A helicopter...
22 June 2022
Abbott Laboratories is opening a big new office at Willis Tower that could bring as many as 450 jobs downtown, a move meant to provide...
08 July 2021
The insurer for the Willis Tower in Chicago is suing the City of Chicago in an attempt to recoup some of its costs in paying...
23 April 2021
EQ Office announced the exciting reopening of Skydeck Chicago at Willis Tower to the public on 23 April, 2021 after completing an extensive redevelopment. The...
03 February 2021
United Airlines is shrinking its Willis Tower headquarters, where it has about 30 percent fewer workers than before the COVID-19 pandemic. The airline today confirmed...
12 January 2021
EQ Office revealed Atmospheric wave wall, a new cultural landmark and the first public art installation in Chicago by globally acclaimed artist Olafur Eliasson. Prominently...
13 October 2020
Reports of the demise of co-working during the pandemic are greatly exaggerated, if you ask the owner of Willis Tower. In a bet on the...
25 September 2020
Dynegy today announced that it has entered into a multi-year partnership with Chicago's iconic Willis Tower to provide 100% renewable electricity to the Tower. "Sustainability...
18 July 2019
EQ Office, the US office portfolio company owned by Blackstone, has reopened Willis Tower’s Wacker Drive lobby, featuring a new, one-of-a-kind art installation created by...
15 April 2019
Skidmore, Owings & Merrill (SOM) has been brought in to deliver Hodder + Partners’ controversial Saint Michael’s tower in Manchester, with the local practice kept...
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