<Tr> <Td_colspan="2"> www.burjkhalifa.ae </Td> </Tr> <P> The Burj Khalifa (Arabic: برج خليفة ‎ ‎, Arabic for "Khalifa Tower"; pronounced English: / ˈbɜːrdʒ kəˈliːfə /), known as the Burj Dubai before its inauguration, is a megatall 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 is the tallest structure in the world since topping out in late 2008 . </P> <P> 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 tower in the world . </P> <P> Burj Khalifa was designed by Adrian Smith, then of Skidmore, Owings & Merrill (SOM), whose firm designed the Willis Tower and 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 architecture of 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 . </P>

What is the old name of burj khalifa