The Top 5 Tallest Buildings in the World;

1. The amount of condensation water collected from the air conditioning system of the Burj Khalifa (which was originally called the Burj Dubi) is said to be equal to 20 Olympic-sized swimming pools per year. The water is recycled and used for landscaping.
2. Changes to the architectural design of the Shanghai World Financial Center resulted in an over-run of more than $200 million US dollars due to the sophistication of the designs which included a structural system re-design, a foundation re-design and increased safety features implemented after the September 11th attacks in New York.
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4. Construction started on Petronas Towers 1 & 2 in 1992 and finished in 1998. César Pelli was the principal architect. Petronas Towers 1 & 2 are located next to Jalan Ampang Street Kuala Lumpur.
5. The height of the International Commerce Centre was scaled back from earlier plans due to regulations that didn't allow buildings to be taller than mountains that surround the city of Hong Kong. The original proposal for this building was called Kowloon Station Phase 7 and it was designed to be 574 m (1,880 ft) tall which would have made it the second tallest building in the world. A five-star (or seven star depending on who your read) 312 room hotel operated by Ritz-Carlton will occupy the top 15 floors of the tower.
6. The Taipei 101 has a circular 660-tonne tuned mass damper which counters seismic and wind-induced movement. It is made from 41 steel plates, and is suspended from eight steel cables. It sits on eight viscous dampers and can move five feet laterally in any direction. It is the largest and heaviest of its type in the world.
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