NEW YORK — One World Trade Center, the giant monolith being built to replace the twin towers destroyed in the Sept. 11 attacks, will lay claim to the title of New York City's tallest skyscraper on Monday. Workers will erect steel columns that will make its unfinished skeleton a little over 1,250 feet high, just enough to peak over the roof of the observation deck on the Empire State Building.
The milestone is a preliminary one. Workers are still adding floors to the so-called "Freedom Tower" and it isn't expected to reach its full height for at least another year, at which point it is likely to be declared the tallest building in the U.S., and third tallest in the world.
Those bragging rights, though, will carry an asterisk.
Crowning the world's tallest buildings is a little like picking the heavyweight champion in boxing. There is often disagreement about who deserves the belt.
In this case, the issue involves the 408-foot-tall needle that will sit on the tower's roof.
Count it, and the World Trade Center is back on top. Otherwise, it will have to settle for No. 2, after the Willis Tower in Chicago.
"Height is complicated," said Nathaniel Hollister, a spokesman for The Council on Tall Buildings and Urban Habitats, a Chicago-based organization considered an authority on such records.
Experts and architects have long disagreed about where to stop measuring super-tall buildings outfitted with masts, spires and antennas that extend far above the roof.
Consider the case of the Empire State Building: Measured from the sidewalk to the tip of its needle-like antenna, the granddaddy of all super-tall skyscrapers actually stands 1,454 feet high, well above the mark being surpassed by One World Trade Center on Monday.
Purists, though, say antennas shouldn't count when determining building height.
An antenna, they say, is more like furniture than a piece of architecture. Like a chair sitting on a rooftop, an antenna can be attached or removed. The Empire State Building didn't even get its distinctive antenna until 1952. The record books, as the argument goes, shouldn't change every time someone installs a new satellite dish.
Excluding the antenna brings the Empire State Building's total height to 1,250 feet. That was still high enough to make the skyscraper the world's tallest from 1931 until 1972.
From that height, the Empire State seems to tower over the second tallest completed building in New York, the Bank of America Tower.
Yet, in many record books, the two skyscrapers are separated by just 50 feet.
That's because the tall, thin mast on top of the Bank of America building isn't an antenna, but a decorative spire.
Unlike antennas, record-keepers like spires. It's a tradition that harkens back to a time when the tallest buildings in many European cities were cathedrals. Groups like the Council on Tall Buildings, and Emporis, a building data provider in Germany, both count spires when measuring the total height of a building, even if that spire happens to look exactly like an antenna.
This quirk in the record books has benefited buildings like Chicago's recently opened Trump International Hotel and Tower. It is routinely listed as being between 119 to 139 feet taller than the Empire State Building, thanks to the antenna-like mast that sits on its roof, even though the average person, looking at the two buildings side by side, would probably judge the New York skyscraper to be taller.
Tallest U.S. buildings
The tallest completed buildings in the United States, as measured from the lowest public entrance to the highest architectural element, not including antennas. After it is finished, One World Trade Center may take over the top spot, but only if you count its rooftop spire, which reaches to 1,776 feet.
1. Willis Tower (formerly Sears Tower), Chicago, 1974: 1,451 feet.
2. Trump International Hotel and Tower, Chicago, 2009: 1,389 feet.
3. Empire State Building, New York, 1931: 1,250 feet.
4. Bank of America Tower, New York, 2009: 1,200 feet.
5. Aon Center, Chicago, 1973: 1,136 feet.
Source: Council on Tall Buildings and Urban Habitats.