how many feet is the world's tallest building
It has a roof height of 828 m (2,717 ft), and with its antenna included, it stands a total height of 829.8 m (2,722 ft), making it the tallest building and the tallest structure in the world. Construction of the Burj Khalifa began in 2004, with the exterior completed 5 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.