CTBUH Journal International Journal on Tall Buildings and Urban Habitat

Tall buildings: design, construction and operation | 2011 Issue III

Special Edition World Trade Center: Ten Years On This Issue

Editor Buildings are the official ribbon cutting ceremony for the Jan Klerks, CTBUH backdrop in front of project followed on April 4, 1973 and [email protected] which we live our commemorated the end of a process dating Associate Editors lives. They are back to the mid-1940s. At a time when most Robert Lau, Roosevelt University markers of both place developers in were focused on [email protected] and time. They are Midtown, the WTC created a powerful Antony Wood, CTBUH/Illinois Institute of Technology [email protected] also storage vessels economic stimulus to and into which we place further encouraged renewal of the Editorial Board tremendous amounts of energy, resources, surrounding urban areas. Ahmad Abdelrazaq, Samsung Corporation and memories. Throughout the construction Mir Ali, University of Illinois at Urbana-Champaign The tragic events of September 11, 2001 were Richard W. Bukowski, Rolf Jensen & Associates, Inc. process, there are a few watermark events a painful reminder of just how much kinetic Mahjoub Elnimeiri, Illinois Institute of Technology that we celebrate. We gather to break the Gary C. Hart, Weidlinger Associates energy and human spirit we invest in the ground, perhaps set the corner stone, Peter Irwin, RWDI many little acts of designing, constructing, Tim Johnson, NBBJ commemorate topping-out of the structure, and occupying a building. It was deeply Zak Kostura, Arup and celebrate the grand opening. In these Gary Lawrence, AECOM humbling for me to see that energy released moments, we wish the project good fortune, Simon Lay, WSP Buildings Ltd. back into the universe. Sam Lee, Scientific Computing Consultants mark our achievements, and reflect on the Tony McLaughlin, Buro Happold successes of our combined efforts. My comfort over the past few years has been Philip Oldfield, University of Nottingham watching the recovery and reconstruction Lester Partridge, AECOM Frank Woolworth celebrated the grand effort: seeing energy and human spirit Jason Pomeroy, Malyan opening of his Woolworth Tower in 1913 with Swinal Samant, University of Nottingham reinvested. I can see the WTC site from my a banquet. The commemorative book he Steve Watts, Davis Langdon LLP office window now. Each day I witness Peter Weismantle, Adrian Smith + Gordon Gill published included a copy of the speeches construction progressing as another slab Michael Willford, Arup given that night. During his own speech, he emerges or the curtain wall surrounds recalls asking how many floors were in his Design & Layout another floor. When I walk to lunch, I pass Tansri Muliani building. When nobody could give him a trucks carrying an assortment of building [email protected] definitive answer, Mr. Woolworth climbed the materials. On sunny days, I enjoy eating lunch Steven Henry stairs all the way to the top of his building so [email protected] in . There, I hear construction he could count the floors for himself. His workers talking about the day’s work or how building was, after all, the world’s tallest Published by the Yankees fared in yesterday’s game. Life in The Council on Tall Buildings and Urban Habitat building and he thought it only proper to © CTBUH 2011 carries on. ISSN: 1946-1186 know exactly how many floors it contained. This year marks the 10th anniversary of the Another great celebration was the grand Council on Tall Buildings and Urban Habitat WTC disaster. We will pause once again to opening of the Building on May S.R. Crown Hall, Illinois Institute of Technology remember those lost and honor the efforts of 3360 South , Chicago, IL 60616 1, 1931. Dignitaries and New York socialites so many, this time with gleaming new t: +1 312 567 3487 turned out for the event. Grandchildren of construction as the backdrop. While this f: +1 312 567 3820 former Governor had the honor of e: [email protected] edition of the Journal is devoted to the after cutting the ribbon and the show-stopper www.ctbuh.org effects of 9/11, we do not intend it as a came when President – with retrospective or a memorial. Instead, we Copyright the push of a button from his desk at the © 2011 Council on Tall Buildings and Urban Habitat. choose to focus on the progress being made – turned on the building’s lights. All rights reserved. No part of this publication may be to reconstruct the WTC site and surrounding reproduced or transmitted in any form or by any means, It was a triumphant day for American areas, and view the impact of the event on electronic or mechanical, without permission in writing construction works too. When the project from the publisher. disciplines around the world. We look forward broke ground on January 22, 1930, to the WTC topping-out ceremonies and was still reeling from the Black Tuesday crash Image Copyright grand openings that mark the achievements CTBUH Journal has endeavored to determine the three months earlier. Despite a faltering global copyright holders of all images. Those uncredited have of our industry toward rebuilding the WTC site economy and growing at been sourced from listed authors or from within CTBUH and revitalizing Lower Manhattan. home, they had built the world’s tallest Print building in only 410 days. Best Regards, This Journal is printed by Source4, Chicago. Front cover: © / Forty two years later, in the fall of 1972, One dbox studio World Trade Center (WTC) officially surpassed Back Cover: World Trade Center site under construction the in height. The Charles Killebrew, CTBUH Trustee © Jan Klerks

2 | This Issue CTBUH Journal | 2011 Issue III Inside

Case Study: , New York News and Events 36 Challenging Attitudes on 14 “While, in an era of supertall buildings, big of new development. The new World Trade Bridging over the tracks was certainly an Center Transportation Hub alone will occupy engineering challenge. “We used state-of-the- numbers are the norm, the numbers at One 74,300 square meters (800,000 square feet) to art methods of analysis in order to design one Codes and Safety serve 250,000 pedestrians every day. Broad of the primary shear walls that extends all the World Trade are truly staggering. But the real concourses (see Figure 2) will connect Tower way up and is being transferred at One to the hub’s PATH services, 12 subway its base to clear the PATH train lines that are 02 This Issue story of One World Trade Center is the lines, the new Fulton Street Transit Center, the crossing it,” explains Yoram Eilon, vice Kenneth Lewis Nicholas Holt World Financial Center and Winter Garden, a president at WSP Cantor Seinuk, the structural innovative solutions sought for the ferry terminal, underground parking, and retail engineers for the project. “In addition, the Jose Torero Authors unprecedented challenges faced in building a and dining venues. layout of below grade structure and columns Kenneth Lewis, Managing Director took into account the dynamic envelope of Nicholas Holt, Technical Director The resulting underground challenges can be Charles Killebrew, Figure 2. Councourse below grade © SOM these train lines. The design of the structure project of this size on such a difficult site.” likened to a four-dimensional chess game. Skidmore, Owings & Merrill LLP But the real story of One World Trade Center is also meets the Port Authority requirements First of all, obstructions exist three the innovative solutions sought for the that these lines remain operable during New York, NY 10005 The world knows what happened in Lower Manhattan on September 11, 2001. The twin dimensionally in overlapping planes at unprecedented challenges faced in building a construction. In order to comply, we designed t: +1 212 298 9300 towers of the World Trade Center and several other buildings were damaged or destroyed, varying depths. Secondly, per the brief, the f: +1 212 298 9500 project of this size on such a difficult site. a steel structure that bridges over the tracks, CTBUH Trustee e: [email protected] and more than 3,000 people were killed. The ground smoldered for months. Rescue was PATH train service was to remain operational which supported the wet concrete loads www.som.com replaced by recovery, which was followed by eight brutal months of removing thousands of and existing structures had to be preserved during construction and was eventually tons of debris from what became known as . What most people do not realize is throughout excavation and construction. Site integrated into the permanent structure.” 38 How WTC Affected Tall Kenneth Lewis that reconstruction of the 6.5-hectare (16-acre) site began soon after the cleanup, due to the Threading steel members, conduits, and Kenneth A. Lewis is a Director in SOM’s New York office. The project team was confronted with He joined the firm in 1986 and has served on a diverse fact that the initial work began underground and was therefore out of sight. shafts through the maze required precision range of projects including mixed-use developments, unprecedented challenges. The site sits over a timing not only to avoid service or commercial towers, corporate headquarters, and Now that buildings are emerging into the 10th anniversary of the attacks in September vast tangle of existing subterranean obstacles. Structural Design healthcare facilities. construction disruptions, but to ensure that light of day, the ambitious redevelopment is 2011. The Port Authority is developing a major The new tower must bridge existing PATH The tower’s structure is designed around a Mr. Lewis began his career at SOM as Senior Designer. subsequent development would not be Building Life Safety Design He has managed and brought to successful clearly visible. One World Trade Center (1WTC), transportation hub. Silverstein Properties, the train tracks adjacent to existing subway tracks, obstructed. massive, redundant steel moment frame completion several projects of enormous scale, designed by Skidmore, Owings & Merrill, is previous developer of 1WTC, is building three as well as accommodate a planned network consisting of beams and columns ® complexity, and visibility, including the award-winning 04 CTBUH News and Events mixed-use Time Warner Center at in rising on the northwest corner of the site. The additional office towers for the site. New York and the in Lower National September 11 Memorial is also under Manhattan, and Brookfield Properties’ Hudson Yards Even with all of these high-profile projects, Competition Entry. He is currently managing construction and will be completed by the 1WTC will dominate the site, not merely as World Trade Center. All of the projects Ken is managing Carl Baldasara, Jon Evenson & New York ’s (and North America’s) tallest are slated to achieve a Gold rating under the USGBC LEED® CS rating system. He was also closely involved in building, but as an icon representing the development of sustainability design guidelines Antony Wood, for the World Trade Center. He is active in the public perseverance, innovation, and urban realm, and his projects have been honored with modernism (see Figure 1). The US$ 3.2 billion numerous design awards. tower, based on a revised 2005 design, now Simon Lay Nicholas Holt rises from a footprint measuring 61 by 61 Directing the technical team in SOM’s New York office, Mr. Holt oversees the detailed meters (200 by 200 feet), set back from the CTBUH Executive Director development and documentation for all of the New site’s northwest corner. Constructed of York office’s projects. Since joining SOM in 1995, he has developed extensive experience working on high-rise concrete and steel, the 104-story tower will and supertall commercial/mixed use towers, financial include a multi-level and trading facilities, health science projects and multi-family residential/hotel towers. reach 417 meters (1,368 feet) above ground. A Mr. Holt is an industry leader in the practical two-story ring supporting broadcasting application of Building Information Modeling (BIM) services will support a spire, which will and the associated implementation of new project delivery models aimed at developing projects more culminate at a symbolic 1,776 feet (541 efficiently and effectively. Recent examples are 250 meters) – 1776 being the year of American 40 An Overview: Urban West , and the Mt. Sinai Center for Science and Medicine, which were among the first major independence. projects in NYC to be designed and documented in a 05 Debating Tall 100% BIM environment. While, in an era of supertall buildings, big Mr. Holt also leads for Architecture Science numbers are the norm, the numbers at One and Ecology (CASE), a research collaboration between World Trade are truly staggering: 5,660 cubic SOM and Rensselaer Polytechnic Institute. With a focus Terrorism meters (200,000 cubic feet) of concrete; on developing new sustainable materials and technologies, CASE blends private sector practicality, 92,920 square meters (1 million square feet) of academic exploration and scientific rigor to seek Opinions for and against on a emergent technologies and develop them for practical exterior glazing; 40,800 metric tons (45,000 US application in buildings. tons) of structural steel; and 241,550 square Sofia Dermisi Figure 1. One World Trade Center © SOM/dbox Studio meters (2.6 million square feet) of office space. topical issue 14 | One World Trade Center, New York CTBUH Journal | 2011 Issue III CTBUHCCTCTBTBTBUUHH JJouJoJournalouournarrnnanal | 201120100111111 IssueIIsssuessuueue IIIIIIII OnOOnenene WWoWorldorlrrldldld TradeTTrraadadeddee CeCCenter,ententntteerr,, NNeNewewew YoYYorkorkrk | 1155 42 Impacts on Building Security 05 What’s on the Web? Measures Featuring new content now Geoff Craighead available on the website Revitalizing Lower Manhattan: 20 World Trade Center in Context

Towers Besides One World Trade Center, Towers 2, 3 “It is nearly impossible to predict when the World Trade Center site will and 4 have been planned along the newly 44 Rethinking Evacuation: aligned , at the eastern be fully rebuilt and occupied. As it is already gradually becoming part of perimeter of the site. Although the 06 CTBUH 2011 Award Winners foundations of Towers 2 and 3 are part of the the New York urban context, it can be argued that there will never be one current ongoing construction, further definitive moment of completion.” development of these buildings has been Rethinking pushed back awaiting market demand. Tower An overview by Jan Klerks, CTBUH Communications Manager/Journal Editor 4, however, is currently under construction. To 2011 Winners of the Best Tall the south of the original site and on the location of the recently demolished Deutsche Almost 10 years after the destruction of the Twin Towers, the reconstruction of the World Trade Center site is in full swing. One World Trade Bank Building, Tower 5 has been planned for Center, which is discussed in the case study paper in this Journal, will be the largest and tallest development on the site, but it is definitely not Antony Wood future development. Located to the north of the only one. In fact, the site will eventually become one of the very few clusters of supertall buildings in the world. As such, it is part of a the World Trade Center site, 7 World Trade development which in significance and importance far exceeds the 65,000 square meters (16 acres) site in Lower Manhattan. The following Center was opened in 2006. All of these Building and Lifetime offers an overview and status update of the components that make up the World Trade Center development. towers are office buildings and no new building has been planned that will carry the Urban Scheme of the then-called Freedom Tower. The plan 10:28 am when the second tower collapsed. number 6 in its name. The master plan for the World Trade Center also contained a number of symbolic An important element in the scheme for the elements, such as a proposed height of 541 The Port Authority of New York and New Achievement Awards site is based on a design by Studio Daniel site is the restoration of the linear Jersey, who was the developer and owner of Figure 3. Tower 2 © Foster + Partners Figure 4. Tower 3, Rogers Stirk Harbour + Partners Libeskind (see Figure 1 and 2). The study was meters (1,776 feet) for the tallest tower thoroughfare of Greenwich, Cortland, Day, © Silverstein Properties (referring to the year in which the Declaration the former World Trade Center, has assumed selected in February 2003 as the master plan and Fulton Streets. As a result, the World Trade responsibility for the development of 3 at 175 Greenwich Street progress of developing Tower 3 depends on for rebuilding the World Trade Center site. This of Independence was signed) and a concept Center site will be more integrated with its World Trade Center, Tower 5, the National Tower 3 is at the center of the various the ability to finance the project. plan proposed a complex program, which called the “wedge of light.” This concept surrounding area compared to the raised September 11 Memorial & Museum, the buildings around the memorial site (see called for the construction of a memorial with positioned the tower faces in such an plaza concept that was laid on top of 12 transportation hub, and overall site Figure 4). As a result, it stands centrally across Tower 4 at 150 Greenwich Street waterfalls, an underground museum, a visitor arrangement that the faces pointed at the sun demolished city blocks in the former World infrastructure. Towers 2, 3, and 4 are being Greenwich Street from the main axis, formed With a height of 298 meters (977 feet), Tower center, retail space, an intermodal transit hub in the sky at the onset and the end of the Trade Center. attack: 8:46 am when the first plane hit and developed by Silverstein Properties of New by the two reflecting pools of the Memorial. 4 is the lowest projected tower in the site (see Features and five office towers spiraling to the height York City, the lease holder of the 10 million The 71-story tower was designed by Rogers Figure 5 and 6). The building was designed by 08 Global News square foot commercial space of the former Stirk Harbour + Partners and will be 378 the Japanese Pritzker Prize-winning ® World Trade Center. meters (1,240 feet) tall when completed. The 7WTC Tower 2 at 200 Greenwich Street Designed by Foster + Partners, Tower 2 is Highlights from the CTBUH Arts Tower 2 planned to rise to 79 stories. When Center 1WTC constructed, the 411-meter (1,348-foot) tall 50 Talking Tall tower will be the second tallest in Transportation Hub & Retail the World Trade Center site and the third Memorial & tallest building in , following global news archive Museum One World Trade Center and the Empire State Tower 3 Building. The sloping roof, consisting of four The Global Impact of 9/11 diamonds inclined toward the memorial (see Figure 3), will provide a visual marker around the skyline of just where the original towers Tower 4 were. Although a completion date has not been projected, foundation work began on June 1, 2010 and should continue until late 2011. Further progress of Tower 2 depends on the demand for office space. Adamson Tower 5 Architects are the executive architects for this Tower as well as Towers 3 and 4. Figure 5. Tower 4, Fumihiko Maki Figure 6. Tower 4 under construction © Jan Klerks 54 Tall Buildings in Numbers Figure 1. World Trade Center Site Plan © SOM Figure 2. World Trade Center Towers © dBoxStudio Case Study © Silverstein Properties New York City Scrapers 20 | Revitalizing Lower Manhattan: World Trade Center in Context CTBUH Journal | 2011 Issue III CTBUH Journal | 2011 Issue III Revitalizing Lower Manhattan: World Trade Center in Context | 21 14 One World Trade Center Kenneth Lewis & Nicholas 56 Design Research Holt Code & Regulations Vertical Architecture STudio 32 Evolution of Building Code Requirements in a Post 9/11 World

“Recommendations from the original Structural 20 Revitalizing Lower Engineering Institute, ASCE and FEMA sponsored report recommended several building code changes. Additional work by Manhattan David Drengenberg Gene Corley NIST and NIBS has resulted in more than 17 Authors David Drengenberg, Engineer code changes.” CTBUH Gene Corley, Senior Vice-President CTLGroup It is not practical to design tall buildings to resist terrorist attacks. However, the terrorist Jan Klerks 5400 Old Orchard Road attacks of September 11, 2001 highlighted several concerns unique to tall buildings subject to Figure 1. Damage to South Face of WTC 2 © NIST Figure 2. Post-Impact Load Redistribution © NIST Skokie, IL 60077 extreme events. Observations resulting from the World Trade Center’s post-attack perfor- t: +1 847 965 7500 f: +1 847 965 6541 mance investigation included: failure of active and passive fire protection systems, impor- 2. Designers should consider fire resistance is provided. Both active and passive systems after major damage, durability of fire systems, e: [email protected] tance of structural redundancy, and performance of egress systems. These observations led to related to member importance. Elements were vulnerable to impact damage. Water and adequate access. Subsequent to the e: [email protected] www.ctlgroup.com recommendations for code modifications. Many recommendations have been incorporated such as transfer girders, truss elements, lines were likely severed, and spray-on publication of their final report, the NIST by the International Code Council into the International Building Code’s 2012 edition. and bracing should have increased fireproofing was stripped away from awarded a contract to the National Institute of

David Drengenberg protection against fire damage protected elements by the initial impact. Building Sciences (NIBS) to convene a panel of 59 CTBUH on the Road David Drengenberg is an engineer in Structural commensurate with the consequences of Without adequate and uninterrupted water building code experts, and begin Attack and Collapse WTC 1 and WTC 2’s ability in particular to Engineering and Mechanics, as well as a member of survive initial impact loads and the resulting failure. supply, sprinkler systems were rendered implementation of the following NIST the Buildings & Facilities Practice Group steering A coordinated terrorist attack launched on committee, at CTLGroup. structural damage is notable. Undoubtedly, ineffectual, and dislodged fireproofing recommendations: September 11, 2001 led to damage and 3. Definitions of credible hazards should be David joined CTLGroup in 2002 with the completion of many hundreds of lives were saved because compromised designed fire ratings. Based on his M.S. in Structural Engineering from the University destruction of structures in New York City and re-evaluated. The world trade center 1. Prevent progressive collapse by of the redundancy and robustness built into these initial observations, fire protection CTBUH events around the of Illinois at Urbana-Champaign. His principal Arlington Virginia, including the World Trade towers “were the first structures outside of development and nationwide adoption of experience with CTLGroup has included: structural the structures. recommendations included the following: investigation and assessment, structural analysis and Center’s twin towers (WTC 1 and WTC 2). This the military and nuclear industries whose standards and code provisions, and design calculations for evaluation of existing unprecedented attack subjected both towers Although WTC 1 and WTC 2 ultimately design considered the impact of a jet 1. Active fire suppression should be develop a standard methodology – WTC: Ten Years On structures, solutions for construction problems, construction-related repair and rehabilitation of to extreme load conditions far beyond those collapsed, they withstood initial structural airliner, the Boeing 707” (FEMA, 2002. accomplished through the use of supported by analytical design tools and existing structures, on-site observation and considered during design. damage for 102 and 56 minutes, respectively. However, these loads fell far short of the redundant systems. practical design. construction services, administration, development of extraordinary loads applied by a far larger, world. repairs and observation of execution of remedial Redundant and robust exterior steel frame 2. To be effective, passive fireproofing must 2. Develop national standards for (1) structural demolition and repairs. Impact by Aircraft and hat truss construction provided for load faster moving aircraft on September 11. remain adhered after impact or conducting wind tunnel testing of Current geopolitical landscapes and Gene Corley Each of the twin towers was struck by redistribution around areas of impact damage, deformation. prototype structures and (2) estimating Gene Corley leads structural evaluation projects commercial Boeing 767-200 aircraft, each with bridging large, damaged areas. In the case of accompanying motivations have raised wind loads and their effects on tall related to industrial, transportation and parking 3. Passive fireproofing must demonstrate facilities, bridges and buildings. His wide range of estimated gross weights in excess of 124,300 WTC 2, photographic evidence shows more the standard of credible hazards. post-event effectiveness. buildings for use in design. experience includes: evaluation of earthquake, fire and kilograms (274,000 pounds), including 37,900 than 30% of south face columns were blast damaged buildings and bridges, investigation of 3. Develop criteria to enhance tall building 24 Introduction distress in prestressed concrete structures, repair of liters (10,000 gallons) of jet fuel, and at speeds destroyed over five stories (FEMA, 2002). Fire Protection and Fire Suppression performance by limiting sway under parking garages damaged by corrosion, evaluation between 750 and 950 km/h (470 and 590 Calculations show that, if not for the damage Passive fire protection was provided for many and repair of high-rise buildings, stadiums, silos and NIST Recommendations lateral load design conditions (e.g., winds bridges, design and construction or repair of mph). These impacts severely damaged caused by fire, these structures could have structural elements. Spandrels, columns, and Following congressional hearings on May 1, and earthquakes). prestressed conventionally reinforced, precast and structural systems, ignited widespread fires, remained globally stable (see Figure 1 and 2). trusses received spray-on application of 60 Book Reviews cast-in-place concrete, foundations and structural steel 2002, the National Institute of Standards and facilities. and ultimately led to collapse of both low-density fireproofing material with a 4. Evaluate the technical basis for Based on these initial observations, structural Technology (NIST), was authorized to produce Gene is one of the world’s foremost experts in structures. Aircraft impact severely damaged specified fire rating of two or three hours. This determining appropriate construction recommendations included the following: a comprehensive study to develop analyzing buildings damaged by bombs, earthquakes, exterior steel columns and the interior core. material has limited capability to remain classification and fire rating requirements fire and tornadoes. He led the federal investigation 1. Structural designers should consider a recommendations for code changes. This into the September 11, 2001, collapse of the World Additionally, damage to active fire suppres- adhered to substrate material under (especially for tall buildings), and explicitly robust and redundant design philosophy. work was completed and many Trade Center’s twin towers. He also conducted the sion systems such as sprinklers, and passive deflection, and is not designed to resist consider factors including: Books on the World Trade investigation of the 1995 collapse of part of the Murrah Individually, structural elements should be recommendations for changes in the Federal Building caused by the Oklahoma City systems such as fireproofing was severe. abrasion or impact. Active fire suppression • timely access by emergency responders 26 Planning the World Trade bombing, and served as expert advisor during the designed to retain sufficient capacity after International Building Code have been would have been provided by standpipes and investigation and trial resulting from the 1993 fatal fire yielding, and be globally configured to adopted. Early observations and • the extent to which redundancy in active at the Branch Davidian complex in Waco, Texas. sprinkler systems that had been retrofitted Early Observations and Recommendations provide multiple load paths after recommendations centered around three fire systems should be credited for into the towers. individual element failures. major areas of concern unique to tall occupant life safety ® Center Structural Performance Sprinkler systems remain operational so long buildings: ability to remain globally stable Despite the terrible loss of life and property, Center: 40 Years Apart as piping is intact, and adequate water supply Jan Klerks 32 | Evolution of Building Code Requirements in a Post 9/11 World CTBUH Journal | 2011 Issue III CTBUH Journal | 2011 Issue III Evolution of Building Code Requirements in a Post 9/11 World | 33 61 Letters 30 Wider Impacts: Tall Buildings Feedback and comments as a Viable Proposition “The WTC showed that we lack an Leslie E. Robertson, William 61 Diary Baker & Eugene Kohn Upcoming tall building events adequate definition of competence…

32 Evolution of Building Code 62 Meet the CTBUH What we truly need is to legislate Requirements in a Post 9/11 Dario Trabucco World competence, not standardized David Drengenberg & Gene 63 CTBUH Organizational solutions.” Corley Member Listings Jose Torero, page 36

CTBUH Journal | 2011 Issue III Inside | 3 The CTBUH Global News is an online resource and archive for all the latest news on tall buildings, urban Global News development and sustainable construction from around the world. For comprehensive industry news, visit the Global News at: http://news.ctbuh.org

Empire State Building, New York © Jan Klerks Conde Nast moving out from 4 Times Sq. © Tansri Muliani Metropolitan Life Tower, New York © Marshall Gerometta

New York City tenant. New York based publishing giant Tower. After careful evaluation, the Port Condé Nast agreed to move into 93,000 Authority have decided that a restaurant is Before we delve into the past, present, and square meters (1 million square feet) of leased not the best and most practical use for the future of New York, we would like to begin space, occupying floors 20 through 41. The space. A public observatory will be developed this overview of the Global News by wishing Midtown based company is now the largest as planned. the Empire State Building a happy birthday! single tenant to be brought into Lower The 381-meter (1,250-foot) tall landmark in Another New York City landmark made the Manhattan in years. The deal, which involves turned 80 years old on news recently, as clothing designer Tommy almost 40% of the total office space available May 1. With a recently completed green Hilfiger announced his plans to convert the in the tower, is considered to be a catalyst for retrofit (see Journal 2010 Issue III: Talking Tall), 213-meter (700-foot) tall Metropolitan Life the development of the World Trade Center which now makes the “grand dame” of Tower at Madison Square Park into a luxury area. Also, the Port Authority of New York and New York’s largest commercial design hotel. The 102-year-old building, which New Jersey announced that there will not be purchaser of 100% renewable energy, the was recently bought by Hilfiger for US$170 a restaurant at the top of One World Trade tower seems to have many good years ahead million, was planned to be converted into Center – a change from the previous Trade of her. condominiums several years ago after Center which featured ownership changed hands multiple times. Down the road in downtown Manhattan, One th th at the 106 and 107 floors of the North Because of the economic recession and the World Trade Center has signed its first anchor strong development of the hotel sector around Madison Square, the 50-story tower, ...dignity which is modeled after St. Mark’s Campanile in Venice, will now be welcoming fashion- minded tourists in the near future. By attaching his name to a chain of hotels, Mr. The World Trade Center should, because of its importance, Hilfiger is following in the footsteps of fellow “become a representation of man’s belief in humanity, his need for designer Giorgio Armani, who opened the individual dignity, his beliefs in the cooperation of men, and Armani Hotel in ’s in 2010. through cooperation, his ability to find greatness. Continuing with the topic of hotels, European ” based hotel group Yotel will soon open a , the lead architect for the former World Trade Center describing his vision for the 669-room hotel on 27 floors of the 1 MiMA project. Remarks at opening ceremonies and dedication April 4, 1973. Tower (Middle of Manhattan), a 63-story glass building designed by Architectonica nearing

8 | Global News CTBUH Journal | 2011 Issue III apartments have buyers and were sold will be back one day to do it again without starting from close to US$3,000 per square one. meter (US$275 per square foot). (389 meters/1,276 feet) is scheduled to become the next world’s tallest residential tower, with the first residents scheduled to In this day and age, no Global News report move in this August. By the end of the year, would be complete without an overview of the Torch is expected to be exceeded in the latest developments in China. So “buckle height by the nearby (381 up” as we run through the latest synopsis of meters/1,250 feet). The (414 more record breaking numbers. meters/1,358 feet) is expected to take the title Located in the top section of ’s in January of 2012. If this was not confusing tallest building, the 484-meter (1,588-foot) tall enough, eventually , set at 516 International Commerce Centre, the meters (1,692 feet) high, and also located in Ritz-Carlton Hong Kong opened on March 29, the , is scheduled to become the claiming the title of “world’s highest hotel” as world’s tallest residential building in 2014. well as the world’s highest swimming pool. While on the topic of Dubai highlights, we The five-star hotel has 312 rooms and is would like to report that our friend French located on floors numbered 102 to 118 of the Spiderman faced his ultimate . Even though the Chinese challenge by climbing Burj Khalifa on March 1 MiMa Tower, New York © Marshall Gerometta floor counting system leaves out some 28. It took Robert little more than six hours to unlucky numbers as floor numbers, the hotel completion west of . The hotel is climb to the top of the 828-meter (2,717-foot) can indeed make some claim to fame, in a good example of combining height with tall landmark. Most of the climbing was done addition to having some of the best density through smart design. Yotel is already during the dark evening hours because of the panoramic views of the city. However, known for the compact rooms it offers at high temperatures during the day. The climb contrary to titles related to being the tallest airports in and Amsterdam, was to inspire over two thousand students building, as of yet there is no official CTBUH reminiscent of a yacht cabin, or even the who attended the opening ceremony of the ruling on how the highest function should be sleeping capsules found in Japan. Now it is 10th annual conference of “Education Without determined. Whatever the ruling is, it will not taking the concept of compactness, Borders” Conference. Being a pre-approved alter the fact that this hotel has the “highest combined with lofty looking design with a climb, Robert had to partially use a safety lowest” floor (if you know what we mean) and lounge atmosphere, to the “Big Apple.” The harness. Knowing Robert, we are guessing he the highest hotel room.  hotel rooms feature a retractable queen-sized bed, a mini-workstation, and a bathroom with a monsoon shower, all in a 16-square meter (170-square foot) size space. 1 MiMA Tower also contains 151 condo units.

Dubai’s Supertall Neighborhood Many may think that construction in Dubai is on the decline because of a tanking real estate market, but projects are still getting delivered in the Gulf State. The completion of supertall residential towers in Dubai Marina is an exciting process to witness, especially when you’re into tall numbers. At 348 meters (1,142 feet) and 86 floors, The Torch became the world’s tallest residential tower in April, surpassing the 323-meter (1,058-foot) tall Tower in ’s Surfers Paradise for the title. The developer, UK-based Select Group, claims that more than 80% of the 676 Dubai Marina, Dubai © SkyscraperCity

CTBUH Journal | 2011 Issue III Global News | 9 Case Study: One World Trade Center, New York

“While, in an era of supertall buildings, big numbers are the norm, the numbers at One World Trade are truly staggering. But the real story of One World Trade Center is the Kenneth Lewis Nicholas Holt innovative solutions sought for the Authors Kenneth Lewis, Managing Director unprecedented challenges faced in building a Nicholas Holt, Technical Director project of this size on such a difficult site.” Skidmore, Owings & Merrill LLP 14 Wall Street New York, NY 10005 The world knows what happened in Lower Manhattan on September 11, 2001. The twin t: +1 212 298 9300 towers of the World Trade Center and several other buildings were damaged or destroyed, f: +1 212 298 9500 e: [email protected] and more than 3,000 people were killed. The ground smoldered for months. Rescue was www.som.com replaced by recovery, which was followed by eight brutal months of removing thousands of tons of debris from what became known as Ground Zero. What most people do not realize is Kenneth Lewis that reconstruction of the 6.5-hectare (16-acre) site began soon after the cleanup, due to the Kenneth Lewis is a Director in SOM’s New York office. He joined the firm in 1986 and has served on a diverse fact that the initial work began underground and was therefore out of sight. range of projects including mixed-use developments, commercial towers, corporate headquarters, and Now that buildings are emerging into the 10th anniversary of the attacks in September healthcare facilities. light of day, the ambitious redevelopment is 2011. The Port Authority is developing a major Kenneth began his career at SOM as Senior Designer. He has managed and brought to successful clearly visible. One World Trade Center (1WTC), transportation hub. Silverstein Properties, the completion several projects of enormous scale, designed by Skidmore, Owings & Merrill, is previous developer of 1WTC, is building three complexity, and visibility, including the award-winning mixed-use Time Warner Center at Columbus Circle in rising on the northwest corner of the site. The additional office towers for the site. New York and the 7 World Trade Center in Lower National September 11 Memorial is also under Manhattan, and Brookfield Properties’ Hudson Yards Even with all of these high-profile projects, Competition Entry. He is currently managing One construction and will be completed by the 1WTC will dominate the site, not merely as World Trade Center. All of the projects Ken is managing are slated to achieve a Gold rating under the USGBC New York City’s (and North America’s) tallest LEED® CS rating system. He was also closely involved in building, but as an icon representing the development of sustainability design guidelines for the World Trade Center. He is active in the public perseverance, innovation, and urban realm, and his projects have been honored with modernism (see Figure 1). The US$3.2 billion numerous design awards. tower, based on a revised 2005 design, now Nicholas Holt rises from a footprint measuring 61 by 61 Directing the technical architecture team in SOM’s New York office, Nicholas Holt oversees the detailed meters (200 by 200 feet), set back from the development and documentation for all of the New site’s northwest corner. Constructed of York office’s projects. Since joining SOM in 1995, he has developed extensive experience working on high-rise concrete and steel, the 104-story tower will and supertall commercial/mixed-use towers, financial include a multi-level observation deck and trading facilities, health science projects and multi-family residential/hotel towers. reach 417 meters (1,368 feet) above ground. A Nicholas is an industry leader in the practical two-story ring supporting broadcasting application of Building Information Modeling (BIM) services will support a spire, which will and the associated implementation of new project delivery models aimed at developing projects more culminate at a symbolic 1,776 feet (541 efficiently and effectively. Recent examples are 250 meters) – 1776 being the year of American West 55th Street, and the Mt. Sinai Center for Science and Medicine, which were among the first major independence. projects in NYC to be designed and documented in a 100% BIM environment. While, in an era of supertall buildings, big He also leads the Center for Architecture Science and numbers are the norm, the numbers at One Ecology (CASE), a research collaboration between SOM World Trade are truly staggering: 5,660 cubic and Rensselaer Polytechnic Institute. With a focus on developing new sustainable materials and meters (200,000 cubic feet) of concrete; technologies, CASE blends private sector practicality, 92,920 square meters (1 million square feet) of academic exploration and scientific rigor to seek emergent technologies and develop them for practical exterior glazing; 40,800 metric tons (45,000 US application in buildings. tons) of structural steel; and 241,550 square

Figure 1. One World Trade Center © SOM/dbox Studio meters (2.6 million square feet) of office space.

14 | One World Trade Center, New York CTBUH Journal | 2011 Issue III of new development. The new World Trade Bridging over the tracks was certainly an Center Transportation Hub alone will occupy engineering challenge. “We used state-of-the- 74,300 square meters (800,000 square feet) to art methods of analysis in order to design one serve 250,000 pedestrians every day. Broad of the primary shear walls that extends all the concourses (see Figure 2) will connect Tower way up the tower and is being transferred at One to the hub’s PATH services, 12 subway its base to clear the PATH train lines that are lines, the new Fulton Street Transit Center, the crossing it,” explains Yoram Eilon, vice World Financial Center and Winter Garden, a president at WSP Cantor Seinuk, the structural ferry terminal, underground parking, and retail engineers for the project. “In addition, the and dining venues. layout of below grade structure and columns The resulting underground challenges can be took into account the dynamic envelope of Figure 2. Concourse below grade © SOM likened to a four-dimensional chess game. these train lines. The design of the structure But the real story of One World Trade Center is First of all, obstructions exist three also meets the Port Authority requirements the innovative solutions sought for the dimensionally in overlapping planes at that these lines remain operable during unprecedented challenges faced in building a varying depths. Secondly, per the brief, the construction. In order to comply, we designed project of this size on such a difficult site. PATH train service was to remain operational a steel structure that bridges over the tracks, and existing structures had to be preserved which supported the wet concrete loads during construction and was eventually Site throughout excavation and construction. Threading steel members, conduits, and integrated into the permanent structure.” The project team was confronted with shafts through the maze required precision unprecedented challenges. The site sits over a timing not only to avoid service or Structural Design vast tangle of existing subterranean obstacles. construction disruptions, but to ensure that The new tower must bridge existing PATH subsequent development would not be The tower’s structure is designed around a train tracks adjacent to existing subway tracks, obstructed. massive, redundant steel moment frame as well as accommodate a planned network consisting of beams and columns 

CTBUHCCTCTBTBTBUUHH JournalJJouJoouournarrnnanal | 201120100111111 IssueIIsssuessuueue IIIIIIII OneOnOnene WWoWorldorlrrldldld TradeTTrraadadeddee Center,CeCententntteerr,, NNeNewewew YoYYorkorkrk | 1515 Twin Towers, New York © Scott Murphy World Trade Center: Ten Years On

“We are aware that, like everything else, the tall building world is forever changing, developing and improving. But now that we have researched the topic, we also believe it has obviously changed more than usual because of the events of 9/11. This very first themed issue of the CTBUH Journal attempts to answer how.”

September 11, 2011, marks 10 years since the same question: How have the events of 9/11 This Journal focuses on the feedback we have Twin Towers of the World Trade Center were changed the tall building world? received regarding these issues. Planning and destroyed. That we all know. In the days Although we specifically didn’t ask colleagues Design, Code and Regulations, and Safety and immediately following the events, we also to share the experiences from the actual day Security are the areas which have seen the knew that the world had changed. What we of the events, many respondents described most number of practical changes in the way didn’t know was how it had changed, or to how they felt on that day. This reinforces that, the professions operate and are being what extent it was going to change. A decade even a decade after the events took place, the regulated, through either code changes, later, we can now look back and reflect on emotional impact was tremendous. educational policies or safety and security how the world has changed. For this Journal, regulations. The variety of responses to 9/11 we set out to explore how the tall building Some colleagues responded that, from a reveal that, even a decade after the events, world has changed because of the events on practical point of view, not a great deal has there is not always consensus on what the that day. changed in their respective field of expertise lessons from that day should be. since 9/11. The events have not necessarily Immediately after the terrorist attacks, some affected their profession directly, nor has it For this special edition of the Journal, we also people declared the end of . changed the way their profession is regulated. look at the former and future visions of the Looking at the hard data since then, it is safe World Trade Center site to find out what can to conclude that this has not been the case. Others take another perspective on the topic. be learnt from comparing the two. Actually, the past decade has been the most They reason that tall buildings were actually Beforehand, the general consensus seems to productive 10 years ever when it comes to tall as safe before 9/11 as they are today, and the be that the former World Trade Center, as buildings. Of the current list of 100 tallest relevant suggestion then is that there is embodied by their Twin Towers, was a buildings in the world, half of those buildings actually very little that can be done against revolutionary feat of engineering, and to have been built in the past ten years. Of the flying airplanes into tall buildings. This point of those who appreciate it, a zenith of modern current 100 tallest residential towers in the view also suggests that whatever security design. However given what we know today, world, an impressive 90% have been measures you introduce at buildings, airports, the previous towers seem to be considered as completed in the past 10 years. Also, since hotels, and other places where people gather, uninspired buildings when urban and 9/11, almost 1,250 buildings of 150 meters someone can always find a way to overcome architectural issues are considered. The new (492 feet) and taller have been completed those safeguards. Some measures seem to be One World Trade Center Tower is presented internationally, which is more than the aimed more at creating a feeling of safety and here as this Journal’s Case Study. roughly 1,125 buildings of that height or taller security, instead of actually making buildings safer. It is the kind of acceptance which We are aware that, like everything else, the tall that were built throughout history prior to building world is forever changing, 9/11. In New York City itself, 21 new towers implies that whatever man creates, man can destroy, and that threats from entities with an developing and improving. But now that we have entered the local list of 100 tallest have researched the topic, we also believe it buildings in the past ten years alone. Perhaps inclination for intentional destruction need to be addressed in the political arena. has obviously changed more than usual more influential than the events of 9/11, it because of the events of 9/11. This very first eventually took a global financial crisis to slow Other colleagues mention that the events of themed issue of the CTBUH Journal attempts down the development of tall buildings, and 9/11 have triggered productive debates to answer how. only noticeably so if your city is not in Asia. within their professional community leading To conclude, we would like to thank all who To get a more in-depth understanding of the to changes in code, practices, procedures, theories and discoveries in an attempt to have contributed or otherwise helped to non-quantitative changes since 9/11, we publish this special edition of the Journal. Your reached out to numerous prominent people minimize the chances of things going wrong, input is much appreciated, as always.  in the tall building world and asked them the through either accident or intent.

The Editorial Team

CTBUH Journal | 2011 Issue III World Trade Center: Ten Years On | 25 Planning & Design Wider Impacts: Tall Buildings as a Viable Proposition

Tall Buildings are Safe! Downs and Ups Leslie Robertson William Baker My take on the development of the tall Two days after the attack on the World Trade building world after 9/11 as a structural Center, I was asked by engineers with the engineer has always been a straightforward Structural Engineering Association of New one: tall buildings are safe. They were safe York (SEAoNY) to put together a group of before 9/11, as they are safe today. If you look Chicago structural engineers to come to New Leslie E. Robertson William Baker at some of the seismic regions, particularly York and assist at Ground Zero. Because all where it comes to structural safety, tall flights were grounded, we had to drive to buildings can be safer than low-rise structures. New York. These terrible opportunities Naturally 9/11 has directed a lot of attention allowed me to see first-hand the extraordinary to the safety of tall buildings, and a lot has destruction at the site of the World Trade been done to make buildings more secure. Center. We knew tall buildings would For all the measures that have been continue to be built but could the very tallest introduced at airports for example, I’m of buildings – the skyscraper – ever fully Eugene Kohn convinced that people with the wrong recover from 9/11? intentions still will be able to find a way to get On September 11, 2001, I was scheduled to Authors in. You’re dealing with people here. It’s almost attend the kickoff meeting in Chicago Leslie E. Robertson, Founder as if the more barriers you create, and the between SOM and Leslie E. Robertson Associates 30 , 47th Floor bigger the walls you build, the more creative for the new , proposed to be the New York, NY 10004 they get to find ways around those walls. world’s tallest building and located in the t: +1 212 750 9000, f: +1 212 750 9002 heart of downtown Chicago. But taking into http://www.lera.com From a structural point of view, it isn’t realistic to think there is much you can do against consideration the ensuing sentiments William Baker, Partner large airplanes flying into tall buildings. Our surrounding tall buildings, Trump Tower was Skidmore, Owings & Merrill LLP quickly reduced in height and stands today as 224 S. Michigan Avenue, Suite 1000 job is to make buildings work, and I feel that Chicago, IL 60604 on top of code, we should be adding our the tenth tallest structure in the world. It t: +1 312 554 9090, f: +1 312 360 4545 experience, sensibility and creative talents to seemed that the fascination and glory that www.som.com advise clients on best practices. The goal is to had previously been associated with Eugene Kohn, Chairman produce structures that are more resilient and skyscrapers had all but disappeared. Kohn Pedersen Fox Associates more robust. Especially when you work on I was therefore intrigued when Emaar, a 11 West New York, NY 10036 projects in countries where tall buildings are a Dubai-based developer, approached SOM in t: +1 212 977 6500, f: +1 212 956 2526 novelty, you sometimes find yourself working 2003 regarding the designing and building of www.kpf.com with a mixture of code adopted from other the world’s tallest structure in Dubai. The countries. I’m not suggesting that this building design initially began as a 518-meter Leslie E. Robertson produces unsafe structures. It means that the (1,699-foot) tall tower and grew to a Leslie Robertson was one of the chief structural engineers of the former World Trade Center in New code hasn’t been optimized for tall buildings staggering 828 meters (2,716 feet), almost York. He has since been structural engineer on in a certain context, which can be cause for double the height of the ill-fated World Trade numerous other projects, including the World Financial Center and the Bank of China Tower in overdesigned or inefficient buildings. towers. In the years that followed the Hong Kong. One issue related to the World Trade Center, commission of Burj Khalifa, many other William Baker which I raised, was parking. I recommended supertall structures were proposed and some William Baker is the Structural Engineering Partner for were built. Skidmore, Owings & Merrill, LLP. Throughout his career, against including parking in the program of Bill has dedicated himself to structural innovation. His the tower to prevent people driving up too Amidst the tragedy of 9/11, architects and best known contribution has been to develop the buttressed core structural system for the Burj Khalifa. close to the core of the building. As designers, engineers were presented with an we shouldn’t just be working towards opportunity to re-examine what we do and Eugene Kohn Eugene Kohn currently serves as the Chairman of Kohn complying with the code, but also try to find look for ways to improve. The industry has Pedersen Fox Associates. In 1976, along with William the best solution to make the buildings work shifted, particularly regarding egress and the Pedersen and Sheldon Fox, he founded KPF. Eugene has served as Partner-in-Charge of many of KPF’s major given the circumstances. way we “tie the building together.” Cores of domestic and international projects and is responsible new towers often exhibit hardened stairs and for many of the firm’s new commissions.

30 | Wider Impacts: Tall Buildings as a Viable Proposition CTBUH Journal | 2011 Issue III ...inverse

I would say that the magnitude“ and impact of 9/11 has proven to be roughly inversely proportional to the distance from Manhattan, and time since the event. ” CTBUH Height Committee Chair Peter Weismantle, Adrian Smith + Gordon Gill Architecture

stay. The proof is that we are still building them. In places like New York, Chicago, Hong Kong, and Shanghai, the skyscraper © CTBUH Ramsey Collection recognizes land value, density, and at times, ego. When you have large populations, exit paths that are more generously sized to or the quality of life that goes on inside and without much land to build on, you’ve got to accommodate rescuers going up as well as around them. The bottom line is that a build tall. A city can’t stay vital and deal with inhabitants going down. It is probable that building’s design shouldn’t be the first barrier growth and the future if tall buildings are most engineers today pay greater attention to of defense against an attack from a jet, from eliminated from their potential vocabulary. To robustness and redundancy in their designs. unnatural forces. The responsibility for replace the World Trade Center towers with 20 ten-story buildings means much more land The events of 9/11 still cause us to pause. Ten defending against such an attack lies would be used (over 20 times, including years later, many of us find it nearly impossible elsewhere. streets), allowing for less open space. to experience a high-rise structure without We can learn how future skyscrapers can be thinking about that day. Skyscrapers, however, designed better by looking at the way Fundamentally altering the way tall buildings have proven they have a place in post-9/11 buildings are being built in other parts of the are seen today, our work speaks to the design and development. It is not residual fear world, such as Asia, South America, the Middle promise of the tall building as a sustainable from the events of that day that has changed East, and even London. The building and fire paradigm, in which individual buildings form the way skyscrapers are developed. Instead codes in Asia, where we are currently part of a larger ecosystem of vertical centers the extraordinary growth of tall towers is more designing a number of tall buildings, are more linked by horizontal networks of public a reflection of a shift in the world’s economy. conservative than they are in the United transportation (even connecting at upper States. These building codes require a levels with walkways). Rather than objects in reinforced-concrete core, refuge floors located isolation, transit-integrated tall buildings Here to Stay every 13 floors, pressurized vestibules leading represent a sustainable model for future Eugene Kohn to the fire stairs, and special for high-rise development.  I think the worst thing we could have done firefighters. Fireman’s lifts in Europe allow the post 9/11 was to stop building important firemen to reach the top of the building buildings, and particularly tall buildings, quickly, which facilitates easier evacuation for because we were afraid someone was going those in need, handicapped people, etc., in to attempt to bring them down. We have to lieu of walking up the stairs as in the World make our buildings as safe as we can, without Trade Center. compromising their significance, their beauty, I am confident that the tall building is here to

CTBUH Journal | 2011 Issue III Wider Impacts: Tall Buildings as a Viable Proposition | 31 Tall Buildings in Numbers

New York City Scrapers By Nathaniel Hollister, Jan Klerks & Antony Wood (all at CTBUH)

New York’s dramatic skyline, over a century in the making, has for years been the envy of cities around the world. From the very birth of the tall building typology, New York has been at the forefront of the scene. Even as recently as the , New York City alone contained over 50% of the world’s 150 m+ buildings. The city’s accomplishments, including both historic and under construction buildings, are impressive when examined in isolation as well as a part of the global whole. The study below examines the make-up and historical development of the New York City skyscraper. In 2010, The Bank of America Tower became the tallest building completed in New York City since the completion of World Trade Midtown 150 m+ buildings By the end of 2011, 221 buildings 150 meters or taller will Center Two in 1973. It was recognized as the CTBUH Best Tall exist in New York City. This number, more than any other 12%(20) Building Americas Winner in 2010. city save Hong Kong, makes up nearly 9% of the global 7%(11) 168 buildings Completion Date: total and 34% of the buildings in the . 76% 20%(33) 2009 of NYC total 63%(105) Architectural Height: In addition to these impressive figures, New York City has 366 m (1,200 ft) Stories: enjoyed a large number of records, including being the 55 Function Primary Use: location of the first 150 meter building and the first Office supertall. Structural Material: Hearst Magazine Tower Composite Map: Location of New York City Skyscrapers Including all buildings 150m+

Office Hotel Other Residential Mixed-use Center

New York Times Tower Notes: 1. Three of New York’s 150 m+ buildings are not located GE Building in Manhattan and therefore not included in this map: The Brooklyner, ; One Hanson Place, Brooklyn; and the Citicorp Building, . Perhaps New York’s most iconic 2. 150 meters was chosen as the minimum height threshold skyscraper, the Empire State for this study to ensure accuracy of information. Building was the world’s tallest building for an unprecedented 41 years, from 1931–1972. It was then replaced by New York’s 1 World Trade Center which was, after two years, surpassed by Chicago’s Sears Tower in 1974.

Metropolitan Life Tower Completion Date: 1931 Architectural Height: 381 m (1,250 ft) Stories: New York’s One World Trade Financial District 150 m+ buildings 102 Center, developed by the Port Primary Use: Authority of New York & New 2%(1) 8%(4) Office Jersey, is set to become North 6%(3) Structural Material: America’s tallest building when 50 buildings Steel it completes in 2013, surpassing 23% 16%(8) Chicago’s by 99 of NYC total 68%(34) meters (325 feet).

Completion Date: 2013 (est.) Function Architectural Height: Eight Spruce Street, 541 m (1,776 ft) completed in 2011, is North Stories: America’s tallest residential 104 building and is being Primary Use: recognized as the CTBUH Best Office Tall Building Americas Winner in Structural Material: 2011. Composite The , Completion Date: Thurgood Marshall completed in 1908, was the 1908 U.S. Court House Completion Date: world’s first building over 150 Architectural Height: 2011 One World Financial Center meters and held the title of 186 m (612 ft) Architectural Height: “World’s Tallest” for one year, Stories: American International Building 265 m (870 ft) before being surpassed by New 47 Stories: York’s 213-meter Metropolitan Primary Use: 76 Life Tower. The Singer Building Office Primary Use: was demolished in 1968 and Structural Material: Residential holds the record for tallest Steel Structural Material: planned demolition. Concrete

54 | Tall Building in Numbers CTBUH Journal | 2011 Issue III Timeline of New York City Skyscraper Completion Dots represent buildings: completion year and height; bars represent total number of buildings completed each year

Office Hotel Other Residential Mixed-use Demolished

1925 1950 1975 2000 2011

7 buildings 45 buildings 111 buildings 180 buildings 221 buildings 3% 20% 50% 81% 100% of 2011 total of 2011 total of 2011 total of 2011 total of 2011 total

400 m 10 bldgs 1931: Empire State Building 1972: 1 and 2010: Bank of America Tower

350 m 8 bldgs 1931: Most active year to 1930: The Chrysler Building date, 10 buildings completed 2007: New York Times Tower (world’s first supertall, 319m)

1932: American International Building 300 m 6 bldgs 1930: Bank of Manhattan 1977: 9/11 1980s: Most active 1933: GE Building decade to date, 44 2011: Eight Spruce Street buildings completed 1913: Woolworth Building 1960: JPMorganChase Tower 250 m 1909: Metropolitan 4 bldgs Life Tower 1929-1939: Great depression 1973-1974: Oil Crisis 1920-1929: “Roaring 20s” 1908: Singer 1936: Thurgood Marshall Building 1914-1918: WWI U.S. Court House 200 m 2 bldgs 1914: Municipal Building 1937-1949: Longest period of tall building inactivity (1939-1945: WWII)

150 m 0 bldgs 1900 19101920 1930 1940 19501960 1970 1980 1990 2000 2011

History of the “World’s Tallest Building” According to CTBUH Height Criteria: Height to Architectural Top

NYC Buildings Non-NYC Buildings

Home World Manhattan Park Row Singer Metropoli- Woolworth Bank of Chrysler Empire State One World Sears Tower 101 Burj Khalifa Insurance Building Life Building Building tan Life Building Manhattan Building Building Trade Center Chicago 1 & 2 Taipei Dubai Building New York Building New York New York Tower New York Building New York New York New York 1974 Kuala Lumpur 2004 2010 Chicago 1890 New York 1899 1908 New York 1913 New York 1930 1931 1972 442 m 1998 508 m 828 m 1885 94 m 1894 119 m 187 m 1909 241 m 1930 319 m 381 m 417 m 1,451 ft 452 m 1,667 ft 2,717 ft 55 m 309 ft 106 m 391 ft 612 ft 213 m 792 ft 283 m 1,046 ft 1,250 ft 1,368 ft 1,483 ft 180 ft 348 ft 700 ft 927 ft

+3939 m +1212 m +1313 m +6+68 m +26 m +2828 m +4+42 m +36 m +6+62 m +36 m +2525 m +1010 m +56 m +320320 m +129129 ft +3939 ft +4+43 ft +221221 ft +8888 ft +9292 ft +135135 ft +118118 ft +20204 ft +118118 ft +8383 ft +3232 ft +18184 ft +1,0501,050 ft

+7+711%% +13%13% +12%12% +57% +14% +13%13% +17% +13%13% +19%19% +9%9% +6+6% +2%2% +12%12% +6+63%3%

60% 59% 85 39 A remarkable 10 of the 16 52% of 145 As late as 1970, New Far from slowing after 85 skyscrapers which have of 165 York City contained 52% the events of 9/11, 39 40% enjoyed the title of the 34% of the world’s 150 m+ buildings 150 m+ have 221 world’s tallest were located of 654 buildings and 59% of 16 completed in NYC in New York, giving the city 20% USA buildings. These from 2002–2011, 18% the title for a combined 9% numbers are now at 9% of the city’s current 221 of 2480 1992– 2002– total. total of 84 out of 126 years. 0% and 34% respectively. 2001 2011 1970 2011

CTBUH Journal | 2011 Issue III Tall Building in Numbers | 55 About the Council

The Council on Tall Buildings and Urban Habitat, based at Institute of Technology in Chicago, is an international not-for-profit organization supported by architecture, engineering, planning, development and construction professionals. Founded in 1969, the Council’s mission is to disseminate multi-disciplinary information on tall buildings and sustainable urban environments, to maximize the international interaction of professionals involved in creating the built environment, and to make the latest knowledge available to professionals in a useful form. The CTBUH disseminates its findings, and facilitates business exchange, through: the publication of books, monographs, proceedings and reports; the organization of world congresses, international, regional and specialty conferences and workshops; the maintaining of an extensive website and tall building databases of built, under construction and proposed buildings; the distribution of a monthly international tall building e-newsletter; the maintaining of an international resource center; the bestowing of annual awards for design and construction excellence and individual lifetime achievement; the management of special task forces/working groups; the hosting of technical forums; and the publication of the CTBUH Journal, a professional journal containing refereed papers written by researchers, scholars and practicing professionals. The Council is the arbiter of the criteria upon which tall building height is measured, and thus the title of "The World’s Tallest Building" determined. CTBUH is the world’s leading body dedicated to the field of tall buildings and urban habitat and the recognized international source for information in these fields.

Council on Tall Buildings and Urban Habitat

S.R. Crown Hall Illinois Institute of Technology 3360 South State Street Chicago, IL 60616 Phone: +1 (312) 567 3487 Fax: +1 (312) 567 3820 Email: [email protected] http://www.ctbuh.org

ISSN: 1946 - 1186