Tallest US skyscraper designed for Chicago

CHICAGO - A twisting 115-storey glass and concrete tower that would be the United States' tallest building may soon grace Chicago's lakefront according to its developer.

Critics compared the proposed 610m Fordham Spire to a giant candle fit for a cake, while others said it was out of place in a post-September 11 world in which landmark skyscrapers could be terrorist targets.

The tower, which would house condominiums and a hotel, is the brainchild of Christopher Carley, chairman of Chicago-based Fordham Co. It was designed by award-winning Spanish-born architect Santiago Calatrava, who is known for his curvaceous bridges, as well as for designing the winged addition to Milwaukee's art museum and the transportation centre to be built on the site of New York's Ground Zero.

The slender tower will soar 444m to its roof and then add a spire to reach 610m, topping the 442m Sears Tower, currently the nation's tallest, and New York's proposed 541m Freedom Tower.

"Chicago was America's birthplace for modern architecture, nurturing the genius of Louis Sullivan, Daniel Burnham, Frank Lloyd Wright and Mies van der Rohe," Carley said in a statement. "We want to carry that tradition into the 21st century and give our city a masterpiece by one of today's indisputable geniuses." At least two previous designs to build the world's tallest building in Chicago fell flat for lack of financing since the Sears Tower lost the title of world's tallest building in 1996 to Kuala Lumpur's twin Petronas Towers.

Current title-holder Taipei 101 in Taiwan is 509m tall but it will soon be eclipsed by the Burj Dubai tower in the United Arab Emirates that may reach 700m.

No cost figure for the Fordham Spire was announced but for it to break even when completed in 2008, prices must average $650 ($960) a square foot, translating to condominiums worth up to $7.5 million, the Tribune reported.

Each floor of the building will be turned 2 degrees from the one below to give the impression of movement. The concave glass facade will deflect lakefront winds and a massive concrete core will allow column-free spaces and 3m floor-to-ceiling windows for its 250 condominiums and a hotel.

Neighbours will have less to worry about at least in terms of the tower's shadow. It will take up only 1300 sq/m at its base and contain just 85,470 sq/m -- compared to 418,000sq/m in the Sears Tower.

Developer and reality television star Donald Trump cited security concerns in scaling down his self-named Chicago hotel-condominium tower now under construction a few blocks from the proposed tower's site near the mouth of the Chicago River.

"In this climate, I would not want to build that building. Nor would I want to live in that building," Trump told the Chicago Tribune.

- REUTERS