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Willis TowerDownload Project Factsheet

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Official Name Willis Tower
Former / Other Name Sears Tower
Type building
Status Completed
Country United States
State Illinois
City Chicago
Street Address 233 South Wacker Drive (Map)
Building Function office
Structural Material steel
Start of Construction 1970
Completion 1974
Global Ranking #9 tallest in the World
Regional Ranking #1 tallest in North America
National Ranking #1 tallest in United States
City Ranking #1 tallest in Chicago
Official Website Willis Tower
Height: Architectural 442.1 meter / 1451 feet
Height: Occupied 412.7 meter / 1354 feet
Height: To Tip 527.0 meter / 1729 feet
Height: Observatory 412.7 meter / 1354 feet
Floors Above Ground 108
Floors Below Ground 3
# of Elevators 104
Top Elevator Speed 8.1 m/s
Tower GFA 416,000 m² / 4,477,787 ft²
Companies Involved
Architect Skidmore, Owings & Merrill
Structural Engineer Skidmore, Owings & Merrill
MEP Engineer Jaros Baum & Bolles
Main Contractor Morse Diesel International
Other Consultants
Façade Enclos Corp.
Vertical Transportation Van Deusen & Associates
• Wind Alan G. Davenport Wind Engineering Group BLWTL
Material Suppliers
• Cladding Cupples
• Elevator Schindler
• Sealants Dow Corning Corporation
Interview: Adrian Smith & Gordon Gill
A.Smith (AS + GG Architecture), G.Gill (AS + GG Architecture), CTBUH Chicago Conference
Decarbonization of Our Central Cities
A.Smith (Adrian Smith + Gordon Gill Architecture), CTBUH Chicago Conference

Technical Papers
Architecture and Structural Form in Tall Steel Buildings
A. Sev (Mimar Sinan Univ.), CTBUH Journal

News Articles
Chicago’s Willis Tower Glass-Floor Skydeck Cracks
CTBUH Global News, 2014-05
Willis Tower Struck by Lightning
CTBUH Global News, 2013-06
Beloved Chicago Skyscrapers Come to Life in Animation
CTBUH Global News, 2013-05
Combining the World's Great Skyscrapers into One Skyline
CTBUH Global News, 2013-01
Willis Tower Exhibit Celebrates Its Omnipresence in the City
CTBUH Global News, 2012-10
Willis Tower Signs Airline Tenant
CTBUH Global News, 2012-08
Site Names World's Ten Best Observation Decks
Viator Travel Blog, 2012-08
Controversy over Willis Tower Joke
CTBUH Global News, 2012-08
Should Antennas Count in Height Measurements
MSNBC.com, 2012-04
Would the Sears Tower have survived 9/11?
The Reader, 2011-09
For Sale: Willis Tower, The Nation's Tallest Building
Chicago Sun-Times, 2011-06
Chicago's Willis Tower to Become a Vertical Solar Farm
inhabitat, 2011-03
Top 10 steel skyscrapers
arabianBusiness.com, 2010-10
Top Illinois Engineering Honors for 2010
Chicago Tribune, 2010-06
Green Giants: Retrofits for the 21st Century
CTBUH, 2010-04
Willis Tower Owner's Rethinking $350-million 'Green' Project
ChicagoRealEstateDaily.com, 2010-03
They Might be Giants
The Architect's Newspaper, 2009-10
Bermuda Broker Willis Gets its Name on America's Tallest
The Royal Gazette, 2009-07
As Unbreakable as ... Glass?
The New York Times, 2009-07
Sears Follows Empire State Example
World Architecture News, 2009-06
What's in a name? Plenty.
Chicago Tribune, 2009-03
Forget Sears Tower With a Silver Paint Job
Chicago Tribune, 2009-03
Sears Tower in Silver?
Chicago Tribune, 2009-02