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Construction of world's tallest tower to begin 18:24 10 December 2004
NewScientist.com Article
Will Knight

Burj Dubai will be nearly half a mile high, at 800 metres tall (Image: SOM)
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The construction of what will be the world's tallest building is set to begin in Dubai, United Arab Emirates. The building contract was awarded to a consortium led by the South Korean Samsung Corporation on Thursday.

The Burj Dubai tower will stand 800 metres tall - just 5 metres shy of half a mile - once completed in 2008. That will be nearly 300 metres taller than the tallest floored building in the world today, the Taipei Tower in Taiwan.

The new tower's unique, three-sided design will ascend in a series of stages, around a supportive central core and boast a total of 160 floors, accessible via a series of double-decker elevators. Its shape will be integral to its impressive size. The design is intended to reduce the impact of wind and to reduce the need for a stronger core - allowing for more space - as it ascends.

"It's almost like a series of buildings stuck together," says Mohsen Zikri, a director at UK engineering consultants Arup. "As you go up you need less and less lifts and less core."

A key challenge will be the logistics involved in construction, Zikri told New Scientist. "You need things to be delivered with military precision or you will have chaos on the ground."

A spokeswoman for Skidmore, Owings & Merrill, the Chicago-based architects firm behind the design in the US, says the shape should prevent wind vortices building up around the tower and causing it to move in the wind. "Wind is the primary thing at this height," she told New Scientist. "The engineers have focused on shaping the building to minimise this effect."

As wind whirls around a tall building it can build into powerful vortices that in turn generate powerful winds on the ground. But the wide base of the Burj Dubai should also prevent wind from causing these disturbances.

Besides beating the Taipei Tower, which stands at 508 metres tall, Burj Dubai will also be considerably taller than the CN tower in Toronto, Canada, which stands at 553 metres tall though is without a multiple floor structure.

Foundation work was recently completed by Turner Construction International, based in New York, US. Above ground construction will now begin under the control of the Samsung Corporation. The contract was awarded by Emaar Properties in Dubai, after an 11-month bidding process.

The tower will be used for offices, residential apartments, hotels and shops and will be surrounded at its base by a man-made lake.

Current height

In February 2007, the Burj Dubai surpassed the Sears Tower as the building with the most floors in the world. As of 20 May 2007 the tower's height was 460.1 meters (1,510 feet), with 129 floors.

It is currently the second tallest building in the world, as measured to the structural top of building (not including antennas). Rising at its current rate of 2-3 floors a week, by September 2007, the Burj Dubai will likely surpass Taipei 101 (509 meters, 1,671 ft) to become the tallest building in the world in all four CTBUH criteria, and the CN Tower (553 meters, 1,815 feet) to become the tallest freestanding land-based structure. However, the CTBUH, and therefore most authorities, will not recognize its world-record height until it is occupied.

Projected height

The projected final height of the Burj Dubai is officially being kept a secret due to competition; however, figures released by a contractor on the project have suggested a height of around 808 metres (2,651 feet). Based on this height, the total number of habitable floors is expected to be around 162. However, on the project's official website, an interior graphic of an elevator panel shows floor numbers up to 195. A more recent article by building subcontractor Persian Gulf Extrusions states a final height "over 940 metres", or at least 3,084 feet, but this has not yet been confirmed by Emaar. This new figure is 24 metres higher than the final height rumoured on burjdubaiskyscraper.com. Another source, from dubaimegaprojects.com reported an estimated final height of 1,011+ metres (3,317 ft.) and a floor count of 216+ floors.

In a recent interview the project manager for Burj Dubai, Greg Sang, was asked directly about the rumour of a final height of 808 m. He responded that he did not know the origin of that figure, and confirmed only that the height would be greater than 700 m. When pressed for a more precise figure, he merely repeated that he was able only to guarantee that the final height would be higher than 700 m, and it would be the world's tallest free-standing structure when completed. In fact, at more than 700 m the Burj Dubai would be the tallest land-based structure of any kind to have ever been built throughout human history.

Architecture and design

The design of Burj Dubai is ostensibly derived from the patterning systems embodied in Islamic architecture, with the triple-lobed footprint of the building based on an abstracted desert flower native to the region. The tower is composed of three elements arranged around a central core. As the tower rises from the flat desert base, setbacks occur at each element in an upward spiraling pattern, decreasing the cross section of the tower as it reaches toward the sky. At the top, the central core emerges and is sculpted to form a finishing spire. A Y-shaped floor plan maximizes views of the Persian Gulf. Viewed from above or from the base, the form also evokes to the onion domes of Islamic architecture.

The exterior cladding of the Burj Dubai will consist of reflective glazing with aluminum and textured stainless steel spandrel panels with vertical tubular fins of stainless steel. The cladding system is designed to withstand Dubai's extreme summer temperatures.