THE NEW WORLD Trade Centre tower in New York has been named the tallest building in the western hemisphere after a panel of architects decided in its favour in a row that could have reduced its official height.

Due to be completed next year, One World Trade Center will replace Chicago’s Willis Tower as the tallest building in the US.

The Height Committee of the Council on Tall Buildings and Urban Habitat said that because the needle atop the New York skyscraper is a permanent spire and not an antenna it can be counted when measuring the structure’s height.

The new World Trade Center tower (right) in New York knocked Chicago’s Willis Tower off its pedestal as the USA’s tallest building today. Pic: AP Photos/File

The needle, measuring 408 feet tall, was more than enough to confirm Chicago is the second city when it comes to tall buildings in the US.

With the needle, 1 World Trade Center is a symbolically important 1,776 feet tall. Without it, the building would have been only 1,368 feet tall — well short of the 1,451-foot Willis Tower.

At stake was more than just the pride of two cities that feast on superlatives and the tourist dollars that might follow, One World Trade Center, with its beacon on top will stand as a monument to those killed in the 9/11 attacks, and its architects had sought to capture the echo of America’s founding year in the structure’s height.

Not only that, but the building’s height without the needle also holds symbolism because at 1,368 feet it is the height of the original World Trade Center.

Graphic showing the height of the One World Trade Center compared against the tallest buildings in the world. Pic: AP Images.

Antony Wood, the council’s executive director, said the needle is particularly important as a “structural and symbolic element.”

Further, he said, the decision to put the spire atop the building was part of a ‘quest” to build a permanent reminder of what the nation went through.

“This was not an economic quest for bragging rights to the U.S.’s tallest,’ he said. “This was a quest to put something meaningful and symbolic on that site because of the horrible history of what happened on that site.”

He said the antennae on top of the Willis Tower help to make the committee’s point about permanence, explaining that when the building went up there were no antennae, and that the original antennae have been replaced with taller ones.

Wood also made another point that, though not a factor on the committee’s decision, is significant, that the Willis Tower will continue to be an attraction for years just like the Empire State Building is decades after it, too, was eclipsed by taller buildings.

“Are any fewer people going to come to Chicago or even travel and visit the Willis Tower because it no longer holds the title of the U.S. tallest? ” he asked. “No,” I don’t think it does.”

In this 10 May 2013 photo, the final piece of spire is hoisted in place on top of 1 World Trade Center. Pic: AP photo/Mark Lennihan.

The Height Committee comprises about two dozen industry professionals from all over the world and is widely recognised as the final arbiter of official building heights around the world . They conferred behind closed doors last week in Chicago, where the world’s first skyscraper appeared in 1884.

The new World Trade Center tower remains under construction and is expected to open next year.

The designers originally had intended to enclose the mast’s communications gear in decorative cladding made of fiberglass and steel. But the developer removed that exterior shell from the design, saying it would be impossible to properly maintain or repair. Without it, the question was whether the mast was now primarily just a broadcast antenna.

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