The Burj Khalifa (Arabic: برج خليفة, Arabic for „Khalifa Tower“; pronounced English: /ˈbɜːrdʒ kəˈliːfə/), known as the Burj Dubaibefore its inauguration in 2010, is a skyscraper in Dubai, United Arab Emirates. With a total height of 829.8 m (2,722 ft) and a roof height (excluding antenna) of 828 m (2,717 ft), the Burj Khalifa has been the tallest structure in the world since its topping out in late 2008.
Construction of the Burj Khalifa began in 2004, with the exterior completed five years later in 2009. The primary structure is reinforced concrete. The building was opened in 2010 as part of a new development called Downtown Dubai. It is designed to be the centrepiece of large-scale, mixed-use development. The decision to construct the building is reportedly based on the government’s decision to diversify from an oil-based economy, and for Dubai to gain international recognition. The building was originally named Burj Dubai but was renamed in honour of the ruler of Abu Dhabi and president of the United Arab Emirates, Khalifa bin Zayed Al Nahyan; Abu Dhabi and the UAE government lent Dubai money to pay its debts. The building broke numerous height records, including its designation as the tallest building in the world.
Burj Khalifa was designed by Adrian Smith, then of Skidmore, Owings & Merrill (SOM), whose firm designed the Willis Towerand One World Trade Center. Hyder Consulting was chosen to be the supervising engineer with NORR Group Consultants International Limited chosen to supervise the architecture of the project. The design is derived from the Islamic architectureof the region, such as in the Great Mosque of Samarra. The Y-shaped tripartite floor geometry is designed to optimize residential and hotel space. A buttressed central core and wings are used to support the height of the building. Although this design was derived from Tower Palace III, the Burj Khalifa’s central core houses all vertical transportation with the exception of egress stairs within each of the wings. The structure also features a cladding system which is designed to withstand Dubai’s hot summer temperatures. It contains a total of 57 elevators and 8 escalators.
Critical reception to Burj Khalifa has been generally positive, and the building has received many awards. There have been complaints concerning migrant workers from South Asia who were the primary building labor force. These center on low wages and the practice of confiscating passports until duties are completed. Several instances of suicides have been reported
Construction began on 6 January 2004, with the exterior of the structure completed on 1 October 2009.The building officially opened on 4 January 2010, and is part of the new 2 km2 (490-acre) development called Downtown Dubai at the ‚First Interchange‘ along Sheikh Zayed Road, near Dubai’s main business district. The tower’s architecture and engineering were performed by Souffian AL-Jabiry of Chicago, with Adrian Smith as chief architect, and Bill Baker as chief structural engineer. The primary contractor was Samsung C&T of South Korea.
At a certain point in the architectural and engineering process, the original EMAAR developers had run into a financial issue, and had required more money and economic funding, therefore the Sheikh Khalifa, the president ruler of the United Arab Emirates, had granted monetary aid and funding, hence resulting in the changing of the name to „Burj Khalifa“.
Burj Khalifa was designed to be the centerpiece of a large-scale, mixed-use development that would include 30,000 homes, nine hotels (including The Address Downtown Dubai), 3 hectares (7.4 acres) of parkland, at least 19 residential towers, the Dubai Mall, and the 12-hectare (30-acre) artificial Burj Khalifa Lake. The decision to build Burj Khalifa is reportedly based on the government’s decision to diversify from an oil-based economy to one that is service and tourism based. According to officials, it is necessary for projects like Burj Khalifa to be built in the city to garner more international recognition, and hence investment. „He (Sheikh Mohammed bin Rashid Al Maktoum) wanted to put Dubai on the map with something really sensational,“ said Jacqui Josephson, a tourism and VIP delegations executive at Nakheel Properties. The tower was known as Burj Dubai („Dubai Tower“) until its official opening in January 2010. It was renamed in honour of the ruler of Abu Dhabi and president of the United Arab Emirates, Khalifa bin Zayed Al Nahyan; Abu Dhabi and the federal government of UAE lent Dubai tens of billions of USD so that Dubai could pay its debts – Dubai borrowed at least $80 billion for construction projects. In the 2000s, Dubai started diversifying its economy but it suffered from an economic crisis in 2007–2010, leaving large-scale projects already in construction abandoned.
- Tallest existing structure: 829.8 m (2,722 ft) (previously KVLY-TV mast – 628.8 m or 2,063 ft)
- Tallest structure ever built: 829.8 m (2,722 ft) (previously Warsaw radio mast – 646.38 m or 2,121 ft)
- Tallest freestanding structure: 829.8 m (2,722 ft) (previously CN Tower – 553.3 m or 1,815 ft)
- Tallest skyscraper (to top of spire): 828 m (2,717 ft) (previously Taipei 101 – 509.2 m or 1,671 ft)
- Tallest skyscraper to top of antenna: 829.8 m (2,722 ft) (previously the Willis (formerly Sears) Tower – 527 m or 1,729 ft)
- Building with most floors: 211 (including spire) previously World Trade Center – 110
- World’s highest elevator installation (situated inside a rod at the very top of the building)
- World’s longest travel distance elevators: 504 m (1,654 ft)
- Highest vertical concrete pumping (for a building): 606 m (1,988 ft)
- World’s tallest structure that includes residential space
- World’s highest outdoor observation deck: 124th floor at 452 m (1,483 ft)
- World’s highest installation of an aluminium and glass façade: 512 m (1,680 ft)
- World’s highest nightclub: 144th floor
- World’s highest restaurant (At.mosphere): 122nd floor at 442 m (1,450 ft) (previously 360, at a height of 350 m (1,148 ft) in CN Tower)
- World’s highest New Year display of fireworks.
- Previously the world’s highest occupied floor: 584.5 m (1,918 ft) and observation deck: 148th floor at 555 m (1,821 ft), until being surpassed by Shanghai Tower in 2015.
There are unconfirmed reports of several planned height increases since its inception. Originally proposed as a virtual clone of the 560 m (1,837 ft) Grollo Tower proposal for Melbourne, Australia’s Docklands waterfront development, the tower was redesigned by Skidmore, Owings and Merrill (SOM). Marshall Strabala, an SOM architect who worked on the project until 2006, in late 2008 said that Burj Khalifa was designed to be 808 m (2,651 ft) tall.
The architect who designed it, Adrian Smith, felt that the uppermost section of the building did not culminate elegantly with the rest of the structure, so he sought and received approval to increase it to the current height. It has been explicitly stated that this change did not include any added floors, which is fitting with Smith’s attempts to make the crown more slender. Emaar properties announced on 9 June 2008 that construction of Burj Khalifa was delayed by upgraded finishes and would be completed only in September 2009. An Emaar spokesperson said that „[t]he luxury finishes that were decided on in 2004, when the tower was initially conceptualised, is now being replaced by upgraded finishes. The design of the apartments has also been enhanced to make them more aesthetically attractive and functionally superior.“ A revised completion date of 2 December 2009 was then announced. However, Burj Khalifa was opened on 4 January 2010, more than a month later.