Saudi billionaire Prince Alwaleed bin Talal has given the go ahead for the construction of the world's tallest tower in the Red Sea port city of Jeddah by signing a US$ 1.2 billion contract with Bin Laden Group on August 2. As reported by ctbuh.org, at over thousand meters and a total construction area of 530 thousand square meters, Kingdom Tower will be the centerpiece and first construction phase of the Kingdom City development on a 5.3 million square meter site in north Jeddah. The tower's height will be at least 172 meters taller than the world's current tallest building, Dubai's 828 meter-tall Burj Khalifa, which was designed by Adrian Smith. Kingdom Tower will feature a Four Seasons hotel, Four Seasons serviced apartments, Class A office space, luxury condominiums and the world's highest observatory. Design development of the tower is under way, with construction to begin imminently. Foundation drawings are complete and the piling for the tower is currently being tendered. Kingdom Tower will cost approximately US$ 1.2 billion to construct, while the cost of the entire Kingdom City project is anticipated to be US$ 20 billion. AS+GG is leading an interdisciplinary design team. The great height of Kingdom Tower necessitates one of the world's most sophisticated elevator systems. The Kingdom Tower complex will contain 59 elevators, including 54 single-deck and five double-deck elevators, along with 12 escalators. Elevators serving the observatory will travel at a rate of 10 meters per second in both directions. Another unique feature of the design is a sky terrace, roughly 30 meters in diameter, at level 157. It is an outdoor amenity space intended for use by the penthouse floor. AS+GG also designed the master plan for the 230 thousand square meters Kingdom Tower Waterfront District, which surrounds the tower and which will include residential and commercial buildings, a shopping mall, high-quality outdoor spaces and other amenities. The Waterfront District provides a cohesive and pedestrian-friendly setting for Kingdom Tower while creating a pleasant neighborhood experience along the Kingdom City lakefront.

Kingdom Tower, Saudi Prince Alwaleed bin Talal's project to erect the world's tallest building in Jeddah, is designed to imitate the contours of a sprouting desert plant. Adrian Smith's task is to make sure it doesn't sway in the wind like one. The American architect has the right resume for the job. He already grappled with effects like horizontal wind divergence and negative pressure high above the Persian Gulf desert when he designed Dubai's "Burj Khalifa", today's highest tower. As explained Adrian Smith during telephone interview to news agency Bloomberg, Kingdom Tower will rise from three separate bases in continuous slopes that end at different heights, helping to balance the building's weight and stabilize it against winds that can reach 190 kilometer per hour at the top. The tower is designed to move about 1 meter side-to-side at 500 meters in the most severe storms that occur once every 50 years or so, he said. The movement will be much less in more typical weather conditions. Designing the world's tallest buildings presents numerous challenges beyond high winds. The observation deck will stick out from the building in an 24 meter-wide disc that was originally designed as a helicopter-landing platform, Smith said. The idea was abandoned after several pilots judged that landing there would be too risky. Water must be pumped up the 163-floor Kingdom Tower in stages, using holding tanks at various levels, to avoid too much pressure building up in the pipes and causing them to burst, Smith said. Evacuation also requires special planning. The Jeddah tower will have emergency refuge rooms every 20 floors, where people can stop to get water and protection as well as emergency instructions while descending to the ground. Smith said he's looking at ways to use the elevators in emergencies rather than following the common practice of banning their use. Smith's design includes a system that collects moisture out of the air and from mechanical systems within the tower, producing enough fresh water each year to fill 14 Olympic-size pools. Summer temperatures in Jeddah, the gateway to Islam's holiest sites in Mecca and Medina, can soar to 40 degrees Celsius with 80 percent humidity. The Kingdom Tower's exterior walls will be made of glass with insulation behind it to help the structure control the heat, Smith said. "We use glass because it's easy to maintain and has longevity," Smith said. "It also reflects the sky and helps the tower feel lighter and more elegant." Apartment prices in Kingdom Tower will probably be comparable to luxury homes in Dubai and a two-bedroom apartment will probably sell for around US$ 800 thousand.

Saudi billionaire Prince Alwaleed bin Talal says he is looking at the world's largest cities, including Shanghai, Moscow, London and New York, as possible locations to build a 1.6-kilometer - high skyscraper that would be the world's tallest building by far. The prince is inviting Dubai's biggest real estate developer Emaar Properties, chaired by Mohammed Alabbar, to team up with his investment firm Kingdom Holding on the project. Alwaleed did not say how the project would be financed if it went ahead, or when it might be completed. He said the cost had yet to be decided. But his ambition reflects the growing confidence of many Gulf companies as they expand overseas, aided by booming economies and rising asset prices in their home countries. He also added countries interested in hosting the world's tallest tower would have to offer attractive financing terms, tax breaks and other government support. Alabbar could not immediately be reached for comment. Over the past year, Emaar has committed itself to several other huge projects in Dubai and nearby countries. Industry experts have said building a 1.6 kilometer skyscraper would involve technical and design challenges, such as how to supply water economically at that height, but would not be impossible. If it is built, the 1.6 kilometer-high tower would surpass the world's current tallest skyscraper, the 828-meter Burj Khalifa in Dubai, as well as the 1 kilometer-high Kingdom Tower now being built by Kingdom Holding in the Saudi Arabian city of Jeddah. The Kingdom Tower is expected to cost around US$ 1.2 billion and will form part of a hotel, retail and luxury residential project. The structure is expected to reach ground level by the end of this year and to be completed in 2017, said Talal Al Maiman, executive director at Kingdom Holding. About 30 percent of useable land in the overall project, which will have an area of about 5.3 million square meters, will be allocated to hotels. The remainder will be divided equally between retail and premium residential space, Al Maiman added. Kingdom Holding, which went public in 2007, has a market value of about $18.5 billion, making it one of the largest listed investment firms in the Middle East. Its assets include stakes in top Western firms such as Citigroup, News Corp and Twitter as well as luxury hotels around the world.