One World Trade Center to Be Tallest US Building

Once it is completed

One World Trade Center in New York City will be the United States' tallest building when completed, beating out Chicago's Willis Tower, according to an announcement Tuesday by the Council on Tall Buildings and Urban Habitat.

The independent organization certifies the official height of skyscrapers and acknowledges record-setting buildings. By the council's criteria, a building's architectural height may include spires and other structural elements, but not antennas, signage or flagpoles, according to its website.

There was some controversy over whether the structure at the top of One World Trade Center was a spire or an antenna. The council's height committee met on November 8 in Chicago to rule on the building's stature.