The Burj Khalifa
A single tower in Downtown Dubai that is half again as tall as anything built before it, paid for by a property developer, named after the ruler of a neighboring emirate, and open to visitors on three floors near the top.
Height and floors
The Burj Khalifa is 828 m (2,717 ft) tall and has 163 floors. The figure is architectural height, measured from the entrance level to the top of the spire. Add the antenna and the total passes 829 m.
Two smaller numbers matter more to anyone inside. The highest occupied floor sits at 585 m, and the top 240 m hold the spire and mechanical plant rather than rooms. For how the measurement is decided, and who decides it, seethe height record page.
Where it is
The tower stands in Downtown Dubai, United Arab Emirates, on Sheikh Mohammed bin Rashid Boulevard beside the Dubai Mall. The address was desert scrub in the 1990s, and Emaar built a whole district around the tower, which is why the surrounding development cost many times the tower itself.
The Dubai Fountain fills the lake at its foot, with jets reaching about 150 m. The tower's air conditioning waters the landscaping: condensation off the cooling coils is collected, roughly 15 million gallons a year, and goes to irrigation rather than down a drain.
Who owns it, and the name
Emaar Properties owns the Burj Khalifa. Emaar is the Dubai developer that built it and still runs the observation decks and the mall. Apartments and offices inside were sold to private buyers, so the tower has hundreds of owners, but the building and its public levels belong to Emaar.
The name changed at the opening. The project was announced and built as Burj Dubai. On 4 January 2010 it opened as the Burj Khalifa, after Sheikh Khalifa bin Zayed Al Nahyan, the president of the UAE and ruler of Abu Dhabi, whose emirate had put billions into Dubai during the 2009 debt crisis. Burj is Arabic for tower. The whole name is roughly "boorj kha-LEE-fa", with the stress on the second syllable of Khalifa.
What it cost
The tower cost about 1.5 billion US dollars. Downtown Dubai around it came to roughly 20 billion, which is the figure most often quoted and the reason the two get confused. Office space was priced above 4,000 dollars per square foot at launch, then the 2009 crash arrived: ten months after opening, 825 of the 900 apartments were still empty. Occupancy reached around 80 percent by 2012.
Who designed it
Adrian Smith designed it at Skidmore, Owings & Merrill, with Bill Baker as structural engineer. Their answer to the height is the buttressed core: a hexagonal concrete core with three wings pressing against it, each wing bracing the other two, so the tower holds itself up the way a tripod does. The plan is a Y, which keeps every apartment within reach of a window and gives the core something to lean on in every direction.
The wings step back 27 times on the way up, in a spiral. Each setback is there to break up the airflow: a smooth tower sheds vortices at one rhythm and starts to rock, and a tower that changes shape every few floors never lets that rhythm build. The outline is often traced toHymenocallis, the spider lily grown in the region, whose petals spread from a central stem. Our page onwhy tall buildings sway covers what the wind does to the ones that do not take that precaution.
Building it, 2004 to 2010
Excavation started in January 2004 and the tower opened six years later. Samsung C&T, BESIX and Arabtec built it, with up to 12,000 workers on site at once. The structure holds 330,000 cubic meters of concrete and 39,000 tonnes of reinforcement, and the concrete was pumped to 606 m in one stage, higher than it had ever been pushed before. Mixes went in at night through the summer, with ice in the water, because Dubai heat sets concrete before it can be placed.
Above the concrete the top 200 m or so are a steel spire, assembled inside the tower and jacked up into position. The facade has 103,000 square meters of glass, specified for the glare and the heat rather than for looks.
Is the Burj Khalifa a hotel?
No. It has one inside. The Armani Hotel Dubai occupies the lower floors with 160 rooms and suites, designed by Giorgio Armani, with Armani residences above it. The rest of the tower is apartments, offices, the decks and the restaurants, so a booking at the Burj Khalifa means a booking at the Armani.
Visiting: tickets and the decks
At The Top is the main observation deck, on levels 124 and 125 at 452 m, reached by elevator from the lower ground floor of the Dubai Mall. At The Top Sky adds level 148 at 555 m, the highest observation deck open to the public anywhere, and costs several times as much. Tickets are timed, sunset slots sell out first, and buying at the door costs more than booking ahead on Emaar's site. A reservation at At.mosphere on level 122 is the cheaper way up, because the table replaces the deck ticket. The elevators run at 10 m per second and reach level 124 in about a minute.
Where it sits in the city
Dubai had almost no tall buildings in 1990.The Dubai page explains how that changed in forty years, andthe supertall page puts the 828 m figure next to the other buildings over 300 m along the same road.