Council on Tall Buildings & Urban Habitat (CTBUH)

Yesterday’s Burj Dubai Inauguration – The Tallest ?? How ?

Yesterday (2010-01-04), the Burj Dubai … recently renamed the Burj Khalifa, in honour of Abu Dhabi’s Ruler … was inaugurated.  Dubayy, as it is known locally, is situated in the United Arab Emirates (UAE).  Contrary to most reports, this building has a height of approximately 550 metres !

Colour photograph of the Burj Khalifa Tower in Dubayy, United Arab Emirates ... which was recently inaugurated on 4th January 2010. A romantic image, for now, of the World's Tallest Building. But ... how 'sustainable' ... and 'fire safe' ... is this building ?
Colour photograph of the Burj Khalifa Tower in Dubayy, United Arab Emirates ... which was recently inaugurated on 4th January 2010. A romantic image, for now, of the World's Tallest Building. But ... how 'sustainable' ... and 'fire safe' ... is this building ? Click to enlarge.

Every single metre counts in the race of the ‘tallest’ !   So, the timing of the following CTBUH(USA) Press Announcement, back in November 2009, was most fortunate.  In my opinion, the most meaningful height criterion is … Height to Occupied Floor.  But, what do you think ?   See below.

However … purposefully tripping you up as you race to read all about the height criteria of Tall and Super-Tall Buildings … we should all know and understand, I hope, that comparing the ‘size’ of structural members is a silly schoolboy’s game.  So, I would like to pose Some Important Questions (discussed, ad nauseam, in previous posts) about the Burj Khalifa Tower …

  1. Dubayy (Dubai) is a crude reproduction of the nightmare that is the 20th Century North American City, i.e. it is on the opposite end of the scale from being ‘sustainable’ !   ‘Greenwashing’ aside … How Sustainable is the Burj Khalifa Tower ?
  2. There is no effective system, in Dubayy, of Independent Monitoring and Technical Control of the processes of building design and construction by Local Authorities Having Jurisdiction (AHJ’s) or Competent Technical Controllers … 

How Fire Safe is the Burj Khalifa Tower … for All of the large population, including People with Activity Limitations (2001 WHO ICF), who will undoubtedly be using/occupying the building during its long life cycle ?

Has the Tower been designed to adequately resist Fire-Induced Progressive Collapse ?   ‘Robustness’ and ‘Disproportionate Damage’ are separate, but related, structural concepts.

During my next visit to Dubayy … I will enjoy looking at, and photographing, the completed building.  But, I will not be entering the Burj Khalifa Tower !

Chicago, 2009-11-17:  The Council on Tall Buildings & Urban Habitat (CTBUH) – the international body which arbitrates on tall building height and determines the title of ‘The World’s Tallest Building’ – has announced a change to its height criteria, as a reflection of recent developments with several super-tall buildings.

The new criteria wording – ‘Height is measured from the level of the lowest, significant, open air, pedestrian entrance to …’ allows for the recognition of the increasing numbers of multi-use tall buildings with often several different entrances at different levels, whilst also accommodating buildings constructed in non-traditional urban or suburban locations.  The CTBUH Height Committee has determined that the previous description of where to measure tall building height from – ‘Height is measured from the sidewalk outside the main entrance to …’ is now no longer sufficient.

This will have an impact on both the height of tall buildings and their relative international height rankings.  Burj Dubai, set to open as the world’s tallest building in January 2010, will now be measured from the lowest of its three main entrances (which opens into the entrance lobby for the tower’s corporate suite office function), while the recently completed Trump International Hotel & Towers in Chicago will be measured from the lower, publicly accessible Chicago Riverwalk.  In the case of Trump, this additional 9 metres (approx.) means that it will surpass the Jin Mao Tower in Shanghai to occupy the rank of 6th tallest on the current list of completed buildings.

“Beginning in 2007, with the knowledge that Burj Dubai would be significantly taller than any structure ever built, the CTBUH Height Committee met to review the criteria by which we recognize and rank the height of buildings”, said Peter Weismantle, Chair of the CTBUH Height Committee and Director of Supertall Building Technology at Adrian Smith + Gordon Gill Architecture in Chicago.  “As one might guess, with the committee being made up of architects, engineers, contractors, developers, building owners and academics, a variety of opinions and views were expressed.  The resulting revisions, almost two years later, reflect a general consensus of the committee in recognizing the most recent trends in tall building development around the world.”

Also in response to the changing designs and forms of tall buildings, the Height Committee has elected to discard its previous ‘Height to Roof’ Category.  “The roof category just doesn’t make sense anymore”, said CTBUH Executive Director Antony Wood.  “In the era of the flat-topped modernist tower, a clearly defined roof could usually be identified, but in today’s tall building world – which is increasingly adopting elaborate forms, spires, parapets and other features at the top of the building – it is becoming difficult to determine a ‘roof’ at all, even less so to measure to it.”

Colour image showing the World's 10 Tallest Buildings ... ranked by the Council on Tall Buildings & Urban Habitat (CTBUH), in November 2009, according to the criterion 'Height to Highest Occupied Floor'. Also included is the Burj Khalifa Tower, which was inaugurated on 4th January 2010.
Colour image showing the World's 10 Tallest Buildings ... ranked by the Council on Tall Buildings & Urban Habitat (CTBUH), in November 2009, according to the criterion 'Height to Highest Occupied Floor'. Also included is the Burj Khalifa Tower, which was inaugurated on 4th January 2010. Click to enlarge.

The Revised CTBUH Height Criteria and Diagrams of the Tallest 10 Buildings in the World as of November 2009 can be found here, ranked according to the three height categories now recognized by CTBUH.  These are: (i) Height to Architectural Top, measured to the topmost architectural feature of the building including spires, but not including antennae, signage, flag poles or other functional-technical equipment;  (ii) Height to Highest Occupied Floor, measured to the level of the highest, consistently occupied floor in the building (thus not including service or mechanical areas which experience occasional maintenance access);  and (iii) Height to Tip, measured to the highest point of the building, irrespective of material or function of the highest element.




Concrete Testing Fraud in New York – 1 World Trade Center


Background & Verification

Early 2008 … a New York Inquiry into the Concrete Testing Industry begins.  At issue is the Structural Reliability of Current Major Public Works Projects in the City, including many Tall Buildings.

Current Internet Search: ‘New York Concrete Testing Inquiry’ … to discover the full measure of fraud and corruption.

I wonder how the U.S. Model Building & Fire Code Organizations … including the U.S. International Code Council … are responding to this growing scandal in New York.   Are they responding at all ?   AND … do they discuss this sort of issue openly, as they heavily ‘promote’ the adoption of U.S. Codes in Developing Countries around the world ?

What is the position of the Council on Tall Buildings & Urban Habitat (CTBUH) ???


2009-09-08 … by Niki May Young, News Editor, World Architecture News(.com) …

Robert LiMandri, New York’s Buildings Commissioner, has announced that concrete tests are to be carried out on 82 New York buildings following safety concerns arising from the indictment of Testwell Laboratories in January and a further firm in July.  Testwell were accused of falsifying concrete mix design reports for the high profile Freedom Tower Project (now 1 World Trade Center), Yankees Stadium, Jet Blue Terminal and a number of other projects and had their license suspended.  Stallone Testing Laboratories were also indicted for falsifying concrete mix design reports in July.

The indictment of Testwell led to a lack of confidence in the safety of over 100 buildings in New York.  Following investigations, 82 buildings are to be re-examined.  The investigations come as part of an announcement by LiMandri of a new comprehensive program to increase the oversight and evaluation of concrete testing at construction projects throughout the City, including projects funded by the City and private developers.  The program includes plans to build a city-owned and operated concrete-testing laboratory and the creation of a new Concrete Unit at the Department Of Buildings (DOB).

The new City laboratory, which will be operated by the Department of Design & Construction (DDC) and is expected to open as early as January, will offer testing services to all City agencies responsible for construction projects.  New York City has 35 private concrete-testing firms currently licensed to do business in the City and the new facility will also make it possible to audit these firms.

“Concrete testing is a critical component of concrete operations, and the results should affirm the strength and quality of materials used for a building under construction,” said LiMandri.  “However, the integrity of concrete-testing practices has come into serious question, and this new laboratory, as well as a new Concrete Unit and re-testing protocol, are three significant measures to ensure concrete testing procedures are lawful and the concrete used meets a project’s specific design requirements.”

DOB denied Testwell’s application to renew its concrete-testing license but a State Supreme Court Judge rejected DOB’s denial of the license renewal.  DOB is now appealing that decision.  Last Friday, DOB revoked Stallone’s concrete-testing license, prohibiting them from testing concrete in the City.  The Department Of Buildings is currently working with property owners named in the Stallone indictment to determine whether a project’s final test results meet the structural design requirements.  If they do not, the affected property owners will also be required to follow the re-testing protocol.

“New Yorkers must be confident the City’s buildings have been built to exacting standards and that the concrete, not usually visible, was mixed to proper construction specifications,” added Design and Construction Commissioner Burney.




Enhanced by Zemanta