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- CTBUH Drawing
- Facts
- Metrics
You must be a CTBUH Member to view this resource.
To Tip:
Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the highest point of the building, irrespective of material or function of the highest element (i.e., including antennae, flagpoles, signage and other functional-technical equipment).Architectural:
Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the architectural top of the building, including spires, but not including antennae, signage, flag poles or other functional-technical equipment. This measurement is the most widely utilized and is employed to define the Council on Tall Buildings and Urban Habitat (CTBUH) rankings of the "World's Tallest Buildings."Occupied:
Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the highest occupied floor within the building.
Above Ground
The number of floors above ground should include the ground floor level and be the number of main floors above ground, including any significant mezzanine floors and major mechanical plant floors. Mechanical mezzanines should not be included if they have a significantly smaller floor area than the major floors below. Similarly, mechanical penthouses or plant rooms protruding above the general roof area should not be counted. Note: CTBUH floor counts may differ from published accounts, as it is common in some regions of the world for certain floor levels not to be included (e.g., the level 4, 14, 24, etc. in Hong Kong).Below Ground
The number of floors below ground should include all major floors located below the ground floor level.Official Name
Willis Tower
Other Names
Sears Tower
Type
Building
Status
Completed
Completion
1974
Country
City
Address
Function
A mixed-use tall building contains two or more functions (or uses), where each of the functions occupy a significant proportion of the tower's total space. Support areas such as car parks and mechanical plant space do not constitute mixed-use functions. Functions are denoted on CTBUH "Tallest Building" lists in descending order, e.g., "hotel/office" indicates hotel function above office function.
Office
Structural Material
Both the main vertical/lateral structural elements and the floor spanning systems are constructed from steel. Note that a building of steel construction with a floor system of concrete planks or concrete slab on top of steel beams is still considered an “all-steel” structure as the concrete elements are not acting as the primary structure.
All-Concrete
Both the main vertical/lateral structural elements and the floor spanning systems are constructed from concrete which has been cast in place and utilizes steel reinforcement bars and/or steel reinforced concrete which has been precast as individual components and assembled together on-site.
All-Timber
Both the main vertical/lateral structural elements and the floor spanning systems are constructed from timber. An all-timber structure may include the use of localized non-timber connections between timber elements. Note that a building of timber construction with a floor system of concrete planks or concrete slab on top of timber beams is still considered an “all-timber” structure as the concrete elements are not acting as the primary structure.
Mixed-Structure
Utilizes distinct systems (e.g. all-steel, all-concrete, all-timber), one on top of the other. For example, a Steel Over Concrete indicates an all-steel structural system located on top of an all-concrete structural system, with the opposite true of Concrete Over Steel.
Composite
A combination of materials (e.g. steel, concrete, timber) are used together in the main structural elements. Examples include buildings which utilize: steel columns with a floor system of reinforced concrete beams; a steel frame system with a concrete core; concrete-encased steel columns; concrete-filled steel tubes; etc. Where known, the CTBUH database breaks out the materials used within a composite building’s primary structural elements.
All-Steel
Energy Label
LEED Recertification Platinum (2019), LEED Gold O+M: Existing Buildings (2016)
Official Website
Height
442.1 m / 1,451 ft
Floors Above Ground
108
Floors Below Ground
3
# of Elevators
104
Top Elevator Speed
8.1 m/s
Tower GFA
423,638 m² / 4,560,001 ft²
Rankings
- By function
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- By material
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Construction Schedule
Construction Start
Completed
Retrofit Start
Retrofit End
Original Companies Involved
Architect
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.
Structural Engineer
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.
MEP Engineer
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 ConsultantOther 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).
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 SupplierMaterial Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Retrofit Companies Involved
Architect
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.
Structural Engineer
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.
MEP Engineer
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.
Contractor
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 ConsultantOther 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).
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 SupplierMaterial Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Original Companies Involved
Owner
The Blackstone Group L.P.
The Moinian Group
Developer
Sears Roebuck and Company
Occupier/Tenant
Abbott; Adtalem Global Education; IMC; United Airlines, Inc.
Architect
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.
Structural Engineer
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.
MEP Engineer
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.
Contractor
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.
Morse Diesel International
Other ConsultantOther 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).
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.
EQ Office; Telos Group
Material SupplierMaterial Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
American Bridge Company
Retrofit Companies Involved
Owner/Developer
The Blackstone Group L.P.
Architect
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.
Structural Engineer
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.
MEP Engineer
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.
Project ManagerThe 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 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.
EQ Office
Contractor
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.
Clayco;Turner Construction Company
Clark Construction Group
Other ConsultantOther 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).
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).
Studio Olafur Eliasson
Rivion
Chicago Scenic Studios, Inc.;Skidmore, Owings & Merrill LLP; Thinc Design
Material SupplierMaterial Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Architect
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.
Structural Engineer
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.
MEP Engineer
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 ConsultantOther 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).
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 SupplierMaterial Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Retrofit Companies Involved
Architect
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.
Structural Engineer
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.
MEP Engineer
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.
Contractor
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 ConsultantOther 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).
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 SupplierMaterial Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, 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 CTBUH Member to view this resource.
Owner
The Blackstone Group L.P.
The Moinian Group
Developer
Sears Roebuck and Company
Occupier/Tenant
Abbott; Adtalem Global Education; IMC; United Airlines, Inc.
Architect
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.
Structural Engineer
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.
MEP Engineer
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.
Contractor
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.
Morse Diesel International
Other ConsultantOther 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).
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.
EQ Office; Telos Group
Material SupplierMaterial Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
American Bridge Company
Retrofit Companies Involved
Owner/Developer
The Blackstone Group L.P.
Architect
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.
Structural Engineer
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.
MEP Engineer
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.
Project ManagerThe 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 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.
EQ Office
Contractor
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.
Clayco;Turner Construction Company
Clark Construction Group
Other ConsultantOther 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).
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).
Studio Olafur Eliasson
Rivion
Chicago Scenic Studios, Inc.;Skidmore, Owings & Merrill LLP; Thinc Design
Material SupplierMaterial Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
Material Supplier refers to organizations which supplied significant systems/materials for a building project (e.g. elevator suppliers, facade suppliers, etc).
CTBUH Initiatives
Willis Tower 50th Anniversary Panel
19 July 2023 - Event
CTBUH Chicago FLC Office Tour Series: Gensler
23 January 2020 - Event
Videos
30 October 2017 |Chicago
Rethinking CTBUH's Height Criteria in the Context of Tall Timber
Recent developments in the design and construction of progressively taller buildings using engineered timber as a structural material raise important questions about the language that...
Research
05 July 2023
We All Love to Get High: Optimizing Observation Deck Design
Terri Meyer Boake
Height is aspirational, and having the best view from that height has become a driver in contemporary tall building design. Likewise, observation decks are a...
Global News
26 September 2023
New Antenna Installed Atop Willis Tower
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...
About Willis Tower
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.
Quick Facts
- Tallest building in the world 1974 - 1998. Preceded byOne World Trade Center and surpassed by thePetronas Tower 1
Videos
30 October 2017 |Chicago
Rethinking CTBUH's Height Criteria in the Context of Tall Timber
Recent developments in the design and construction of progressively taller buildings using engineered timber as a structural material raise important questions about the language that...
16 March 2017 |Chicago
Building Tall Skyscraper Lecture Series: How High Can We Go?
Thursday, March 16, 2017. Chicago, United States of America. Hosted in collaboration with the Chicago Architecture Foundation, the first lecture of the series Building Tall...
26 October 2015 |Chicago
Developing Tall in the New York Context
Gary Barnett, Extell Development Corporation; Ric Clark, Brookfield Properties; Joseph Moinian, Moinian Group; and Larry Silverstein, Silverstein Properties, discuss development in New York City and...
11 June 2013 |Chicago
From London to Chicago: The Willis Group and Tall Buildings
From the 1970’s seminal Willis Faber Dumas Ipswich building, through 51 Lime Street London (winner of the CTBUH 2008 Best Tall Building Europe award), to...
11 June 2013 |Chicago
Interview: Emerging Corporate Mobility
Carmine Bilardello of Willis Group is interviewed by Jeff Herzer during the 2013 CTBUH London Conference at The Brewery, London. Carmine talks about emerging corporate...
20 September 2012 |Chicago
Interview: Management of Tall Buildings
Tony Long of CBRE is interviewed by Jeff Herzer during the 2012 CTBUH Shanghai Congress at the Jin Mao, Shanghai. Tony talks about the management...
03 November 2011 |Chicago
Lynn S. Beedle Lifetime Achievement Award: 40 Years of Designing the Supertall
As one of the world’s foremost experts on supertall buildings, Adrian has contributed greatly to the development of this highly specialized building type. Adrian will...
10 October 2011 |Chicago
Tall Tales: Interrogating the typology of the Tall Building
The ongoing and ubiquitous project of modernism has acclimated humanity to the universality of the tall building as a type. Transformations and mutations of the...
23 October 2009 |Chicago
Chicago: 125 Years of Tall – Reflections
In the city where tall buildings began, this presentation highlights the historical trends, drivers and challenges behind tall buildings and sustainable urban development; what city...
23 October 2009 |Chicago
Interview: Retrofit of the Willis Tower
Adrian Smith & Gordon Gill of AS + GG Architecture are interviewed by Jeff Herzer during the 2009 CTBUH Chicago Conference at Illinois Institute of...
02 November 2008 |Chicago
Founder and First Chairman 'Lynn Beedle'
Biography about Lynn Beedle and the Council on Tall Buildings, narrated by his son David and shown during the first annual awards dinner. For his...
30 October 2017 |Chicago
Rethinking CTBUH's Height Criteria in the Context of Tall Timber
Recent developments in the design and construction of progressively taller buildings using engineered timber as a structural material raise important questions about the language that...
16 March 2017 |Chicago
Building Tall Skyscraper Lecture Series: How High Can We Go?
Thursday, March 16, 2017. Chicago, United States of America. Hosted in collaboration with the Chicago Architecture Foundation, the first lecture of the series Building Tall...
26 October 2015 |Chicago
Developing Tall in the New York Context
Gary Barnett, Extell Development Corporation; Ric Clark, Brookfield Properties; Joseph Moinian, Moinian Group; and Larry Silverstein, Silverstein Properties, discuss development in New York City and...
11 June 2013 |Chicago
From London to Chicago: The Willis Group and Tall Buildings
From the 1970’s seminal Willis Faber Dumas Ipswich building, through 51 Lime Street London (winner of the CTBUH 2008 Best Tall Building Europe award), to...
11 June 2013 |Chicago
Interview: Emerging Corporate Mobility
Carmine Bilardello of Willis Group is interviewed by Jeff Herzer during the 2013 CTBUH London Conference at The Brewery, London. Carmine talks about emerging corporate...
20 September 2012 |Chicago
Interview: Management of Tall Buildings
Tony Long of CBRE is interviewed by Jeff Herzer during the 2012 CTBUH Shanghai Congress at the Jin Mao, Shanghai. Tony talks about the management...
03 November 2011 |Chicago
Lynn S. Beedle Lifetime Achievement Award: 40 Years of Designing the Supertall
As one of the world’s foremost experts on supertall buildings, Adrian has contributed greatly to the development of this highly specialized building type. Adrian will...
10 October 2011 |Chicago
Tall Tales: Interrogating the typology of the Tall Building
The ongoing and ubiquitous project of modernism has acclimated humanity to the universality of the tall building as a type. Transformations and mutations of the...
23 October 2009 |Chicago
Chicago: 125 Years of Tall – Reflections
In the city where tall buildings began, this presentation highlights the historical trends, drivers and challenges behind tall buildings and sustainable urban development; what city...
23 October 2009 |Chicago
Interview: Retrofit of the Willis Tower
Adrian Smith & Gordon Gill of AS + GG Architecture are interviewed by Jeff Herzer during the 2009 CTBUH Chicago Conference at Illinois Institute of...
02 November 2008 |Chicago
Founder and First Chairman 'Lynn Beedle'
Biography about Lynn Beedle and the Council on Tall Buildings, narrated by his son David and shown during the first annual awards dinner. For his...
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Research
05 July 2023
We All Love to Get High: Optimizing Observation Deck Design
Terri Meyer Boake
Height is aspirational, and having the best view from that height has become a driver in contemporary tall building design. Likewise, observation decks are a...
16 May 2023
The Economics of Record-Breaking Height
Jason Barr & Peter A. Weismantle
This paper reviews the development history of record-breaking skyscrapers to better understand their economics. Given how tall they are, the supposed reason for their construction...
25 June 2020
Curtain Wall Façades on the New Generation of Supertall Buildings Present and Future Directions
Sae Hwang Oh, Adrian Smith + Gordon Gill Architecture
Beginning in the late 19th century, construction of skyscrapers spread throughout Chicago, New York City, and then the world as demand of space in buildings...
28 October 2019
Bringing an Icon into the Future: Willis Tower
Stephen Katz, Gensler
Few buildings are as iconic as Willis Tower. Generations of Chicagoans have a collective memory of this building playing a role in their entire lives....
28 October 2019
World’s Biggest (Tall) Buildings
Carol Willis, The Skyscraper Museum
In both professional circles and in the public eye, the subject of the World’s Tallest Building (WTB) has held the spotlight for more than a...
01 September 2018
Developments of Structural Systems Toward Mile-High Towers
Kyoung Sun Moon, Yale University School of Architecture
Tall buildings which began from about 40 m tall office towers in the late 19th century have evolved into mixed-use megatall towers over 800 m....
Ermell_ccbysa.jpg&f=jpg&w=240)
19 January 2016
Interactive Study on Year in Review: Tall Trends of 2015
Jason Gabel, Marty Carver & Marshall Gerometta, CTBUH
CTBUH has determined that 106 buildings of 200 meters’ height or greater were completed around the world in 2015 – setting a new record for...
24 August 2015
World’s Highest Observation Decks
CTBUH Research
Perhaps no element of a tall building is more closely related to the pure pleasure of standing high in the sky and taking in the...
28 January 2014
Debating Tall: Antennas vs. Spires
Larry Silverstein, Siliverstein Properties Inc.; Dario Trabucco, IUAV University of Venice
The CTBUH’s Height Committee ratified the architectural height of One World Trade Center last November, touching off massive media coverage and opening up complicated mixed...
01 August 2013
Imagining the Tall Building of the Future
Josef Hargrave & Ralph Wilson, Arup
Predicting the future is an impossible task. One will never get it absolutely right. However, that does not make it a pointless exercise. Instead, such...
27 January 2012
Debating Tall: A Supertall Future in the US?
Adrian Smith, Adrian Smith + Gordon Gill Architecture; Paul Beitler, Beitler Real Estate Services LLC
In 1990, only 11 buildings in the world could be counted as a “supertall” (defined as a building over 300 meters tall), and all but...
13 April 2011
Tall and Urban: An Analysis of Global Population and Tall Buildings
CTBUH Research
Tall buildings are spreading across the globe at an ever-increasing rate. This study demonstrates the relationship between population and tall buildings across those countries and...
12 June 2008
The Tallest Buildings in the World: Past, Present & Future
CTBUH Research
Over time, the average height of the 100 tallest buildings in the world has been steadily increasing. However, by 2010, this average height will have...
01 May 2001
Integrating Architecture and Structural Form in Tall Steel Building Design
Aysin Sev, Mimar Sinan University
This paper places the integration of structural and architectural design in an historical perspective and discusses the current approaches to the integration of structural and...
05 July 2023
We All Love to Get High: Optimizing Observation Deck Design
Terri Meyer Boake
Height is aspirational, and having the best view from that height has become a driver in contemporary tall building design. Likewise, observation decks are a...
16 May 2023
The Economics of Record-Breaking Height
Jason Barr & Peter A. Weismantle
This paper reviews the development history of record-breaking skyscrapers to better understand their economics. Given how tall they are, the supposed reason for their construction...
25 June 2020
Curtain Wall Façades on the New Generation of Supertall Buildings Present and Future Directions
Sae Hwang Oh, Adrian Smith + Gordon Gill Architecture
Beginning in the late 19th century, construction of skyscrapers spread throughout Chicago, New York City, and then the world as demand of space in buildings...
28 October 2019
Bringing an Icon into the Future: Willis Tower
Stephen Katz, Gensler
Few buildings are as iconic as Willis Tower. Generations of Chicagoans have a collective memory of this building playing a role in their entire lives....
28 October 2019
World’s Biggest (Tall) Buildings
Carol Willis, The Skyscraper Museum
In both professional circles and in the public eye, the subject of the World’s Tallest Building (WTB) has held the spotlight for more than a...
01 September 2018
Developments of Structural Systems Toward Mile-High Towers
Kyoung Sun Moon, Yale University School of Architecture
Tall buildings which began from about 40 m tall office towers in the late 19th century have evolved into mixed-use megatall towers over 800 m....
19 January 2016
Interactive Study on Year in Review: Tall Trends of 2015
Jason Gabel, Marty Carver & Marshall Gerometta, CTBUH
CTBUH has determined that 106 buildings of 200 meters’ height or greater were completed around the world in 2015 – setting a new record for...
24 August 2015
World’s Highest Observation Decks
CTBUH Research
Perhaps no element of a tall building is more closely related to the pure pleasure of standing high in the sky and taking in the...
28 January 2014
Debating Tall: Antennas vs. Spires
Larry Silverstein, Siliverstein Properties Inc.; Dario Trabucco, IUAV University of Venice
The CTBUH’s Height Committee ratified the architectural height of One World Trade Center last November, touching off massive media coverage and opening up complicated mixed...
01 August 2013
Imagining the Tall Building of the Future
Josef Hargrave & Ralph Wilson, Arup
Predicting the future is an impossible task. One will never get it absolutely right. However, that does not make it a pointless exercise. Instead, such...
27 January 2012
Debating Tall: A Supertall Future in the US?
Adrian Smith, Adrian Smith + Gordon Gill Architecture; Paul Beitler, Beitler Real Estate Services LLC
In 1990, only 11 buildings in the world could be counted as a “supertall” (defined as a building over 300 meters tall), and all but...
13 April 2011
Tall and Urban: An Analysis of Global Population and Tall Buildings
CTBUH Research
Tall buildings are spreading across the globe at an ever-increasing rate. This study demonstrates the relationship between population and tall buildings across those countries and...
12 June 2008
The Tallest Buildings in the World: Past, Present & Future
CTBUH Research
Over time, the average height of the 100 tallest buildings in the world has been steadily increasing. However, by 2010, this average height will have...
01 May 2001
Integrating Architecture and Structural Form in Tall Steel Building Design
Aysin Sev, Mimar Sinan University
This paper places the integration of structural and architectural design in an historical perspective and discusses the current approaches to the integration of structural and...
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Global News
26 September 2023
New Antenna Installed Atop Willis Tower
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
Laboratory Company Opening Office in Chicago's Tallest Building
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
Insurance Company Sues City of Chicago After Skyscraper Floods
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
Skydeck at Chicago's Tallest Building Reopens Featuring a New Interactive Museum
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
Airline Reduces Chicago Tower Footprint After Sweeping COVID-19-Related Cuts
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
New Art Installation Revealed at Chicago's Tallest Tower
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
Iconic Chicago Tower Bets on the Future of Co-Working
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
New Partnership Brings Renewable Energy to Chicago Landmark Tower
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
Transformation of Chicago’s Willis Tower Begins with New Art-Filled Lobby
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
New Architects Brought in for Manchester’s St. Michael’s Tower
Skidmore, Owings & Merrill (SOM) has been brought in to deliver Hodder + Partners’ controversial Saint Michael’s tower in Manchester, with the local practice kept...
26 September 2023
New Antenna Installed Atop Willis Tower
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
Laboratory Company Opening Office in Chicago's Tallest Building
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
Insurance Company Sues City of Chicago After Skyscraper Floods
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
Skydeck at Chicago's Tallest Building Reopens Featuring a New Interactive Museum
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
Airline Reduces Chicago Tower Footprint After Sweeping COVID-19-Related Cuts
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
New Art Installation Revealed at Chicago's Tallest Tower
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
Iconic Chicago Tower Bets on the Future of Co-Working
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
New Partnership Brings Renewable Energy to Chicago Landmark Tower
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
Transformation of Chicago’s Willis Tower Begins with New Art-Filled Lobby
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
New Architects Brought in for Manchester’s St. Michael’s Tower
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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CTBUH Initiatives
19 July 2023
Willis Tower 50th Anniversary Panel
Chicago Architecture Center, Council on Tall Buildings and Urban Habitat (CTBUH) and Skidmore, Owings & Merrill (SOM) are teaming up to celebrate Willis Tower’s 50th year with an evening panel of architecture & engineering experts. Hear from those who worked on the historic redevelopment and transformed the iconic building into what it is today.
23 January 2020
CTBUH Chicago FLC Office Tour Series: Gensler
Join the CTBUH Chicago Future Leaders Committee for a tour of Gensler's downtown Chicago office space! The afternoon event will feature a short presentation on Gensler's current work.
28 August 2019
CTBUH Chicago Tours Willis Tower Renovations
CTBUH Chicago led an illuminating tour of the wholesale renovation of the base of Willis Tower, the largest such construction project to take place since the building’s completion
11 July 2019
10th World Congress Reception: Step Onto the Willis Tower Ledge
This special reception will give VIPs the opportunity to let loose in the fantastic setting of Willis Tower (formerly Sears Tower), Chicago’s current tallest building (442 meters).
2 May 2019
CTBUH 50th Anniversary: Moments in History #4
CTBUH Moment in History #4 discusses the controversial claim by the Petronas Towers for the title of “World’s Tallest Building” over the record holder at the time, Willis Tower.
28 March 2019
CTBUH 50th Anniversary: Moments in History #3
"CTBUH 50th Anniversary: Moments in History #3" explores the impact that CTBUH Chairman Fazlur R. Khan, partner, Skidmore Owings & Merrill, had on the tall building industry.
29 November 2018
Building Tall Lecture Addresses Skyscraper Renovations
The latest event in the Building Tall Lecture Series, hosted by the Chicago Architecture Center and CTBUH, featured a panel on revitalizing iconic skyscrapers.
1 February 2018
Fourth Building Tall Lecture Series: Greening Tall
The Chicago Architecture Foundation (CAF) and CTBUH hosted a panel discussion on the movement to incorporate green features into tall buildings.
7 December 2017
CTBUH Founder, Dr. Lynn Beedle, at 100
The founder of the CTBUH, Dr. Lynn Beedle, a professor and eventually director of the Fritz Engineering Laboratory at Lehigh University, would have been 100 years old on December 7.
13 October 2016
Top Company Rankings: The World’s 100 Tallest Buildings
The Council is pleased to announce the Top Company Rankings for numerous disciplines as derived from the list of projects appearing in 100 of the World’s Tallest Buildings.
30 October 2015
Chicago Regional Tour
CTBUH 2015 delegates toured Chicago and its architectural marvels. From recently constructed skyscrapers to the modern marvel of Willis Tower, which held the tallest title for 25 years.
29 May 2015
EMI Lead Chicago Tall-Building Study Trip
A group of 20 Belgian real estate professionals traveled to Chicago from May 25-29 to visit several tall buildings, and related developments as part of a CTBUH Belgium study trip.
12 June 2014
CCHRB Addresses Question: “Refurbish, Repurpose or Replace?”
A recent seminar of CCHRB, co-sponsored by CTBUH, thoroughly examined the question of how cities should deal with existing, outdated tall buildings.
1 November 2013
Tongji University Faculty and Students Visit Chicago
“Towards Zero Carbon,” a collaborative design studio between Tongji University, CTBUH and the Illinois Institute of Technology, made a week-long visit to Chicago in November.
6 November 2011
CTBUH Going Up!
For the third year, some of the sports challenged staff members and friends of CTBUH participated in the SkyRise Chicago stair climbing race.
14 November 2010
CTBUH Running Up the Willis Tower
CTBUH staff braved the chance to climb up all of the 2,109 stairs to the 103rd floor of Chicago Willis (formerly Sears) Tower.
16 December 2009
Height: The History of Measuring Tall Buildings
This article describes some of the events which took place in the Council's long, and sometimes complex, history of measuring tall buildings.
29 October 2009
Willis/Sears Tower Tour
Members of CTBUH staff had a unique opportunity to see the in and outs of the Willis Tower (formerly Sears Tower) in Chicago.
19 July 2023
Willis Tower 50th Anniversary Panel
Chicago Architecture Center, Council on Tall Buildings and Urban Habitat (CTBUH) and Skidmore, Owings & Merrill (SOM) are teaming up to celebrate Willis Tower’s 50th year with an evening panel of architecture & engineering experts. Hear from those who worked on the historic redevelopment and transformed the iconic building into what it is today.
23 January 2020
CTBUH Chicago FLC Office Tour Series: Gensler
Join the CTBUH Chicago Future Leaders Committee for a tour of Gensler's downtown Chicago office space! The afternoon event will feature a short presentation on Gensler's current work.
28 August 2019
CTBUH Chicago Tours Willis Tower Renovations
CTBUH Chicago led an illuminating tour of the wholesale renovation of the base of Willis Tower, the largest such construction project to take place since the building’s completion
11 July 2019
10th World Congress Reception: Step Onto the Willis Tower Ledge
This special reception will give VIPs the opportunity to let loose in the fantastic setting of Willis Tower (formerly Sears Tower), Chicago’s current tallest building (442 meters).
2 May 2019
CTBUH 50th Anniversary: Moments in History #4
CTBUH Moment in History #4 discusses the controversial claim by the Petronas Towers for the title of “World’s Tallest Building” over the record holder at the time, Willis Tower.
28 March 2019
CTBUH 50th Anniversary: Moments in History #3
"CTBUH 50th Anniversary: Moments in History #3" explores the impact that CTBUH Chairman Fazlur R. Khan, partner, Skidmore Owings & Merrill, had on the tall building industry.
29 November 2018
Building Tall Lecture Addresses Skyscraper Renovations
The latest event in the Building Tall Lecture Series, hosted by the Chicago Architecture Center and CTBUH, featured a panel on revitalizing iconic skyscrapers.
1 February 2018
Fourth Building Tall Lecture Series: Greening Tall
The Chicago Architecture Foundation (CAF) and CTBUH hosted a panel discussion on the movement to incorporate green features into tall buildings.
7 December 2017
CTBUH Founder, Dr. Lynn Beedle, at 100
The founder of the CTBUH, Dr. Lynn Beedle, a professor and eventually director of the Fritz Engineering Laboratory at Lehigh University, would have been 100 years old on December 7.
13 October 2016
Top Company Rankings: The World’s 100 Tallest Buildings
The Council is pleased to announce the Top Company Rankings for numerous disciplines as derived from the list of projects appearing in 100 of the World’s Tallest Buildings.
30 October 2015
Chicago Regional Tour
CTBUH 2015 delegates toured Chicago and its architectural marvels. From recently constructed skyscrapers to the modern marvel of Willis Tower, which held the tallest title for 25 years.
29 May 2015
EMI Lead Chicago Tall-Building Study Trip
A group of 20 Belgian real estate professionals traveled to Chicago from May 25-29 to visit several tall buildings, and related developments as part of a CTBUH Belgium study trip.
12 June 2014
CCHRB Addresses Question: “Refurbish, Repurpose or Replace?”
A recent seminar of CCHRB, co-sponsored by CTBUH, thoroughly examined the question of how cities should deal with existing, outdated tall buildings.
1 November 2013
Tongji University Faculty and Students Visit Chicago
“Towards Zero Carbon,” a collaborative design studio between Tongji University, CTBUH and the Illinois Institute of Technology, made a week-long visit to Chicago in November.
6 November 2011
CTBUH Going Up!
For the third year, some of the sports challenged staff members and friends of CTBUH participated in the SkyRise Chicago stair climbing race.
14 November 2010
CTBUH Running Up the Willis Tower
CTBUH staff braved the chance to climb up all of the 2,109 stairs to the 103rd floor of Chicago Willis (formerly Sears) Tower.
16 December 2009
Height: The History of Measuring Tall Buildings
This article describes some of the events which took place in the Council's long, and sometimes complex, history of measuring tall buildings.
29 October 2009
Willis/Sears Tower Tour
Members of CTBUH staff had a unique opportunity to see the in and outs of the Willis Tower (formerly Sears Tower) in Chicago.
There are no results for your search query. Please try a different variation.
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