Controversy had swirled around the height of the skyscraper for months, with the debate focused on whether the 408-foot spire at the top of One World Trade Center would count towards its symbolic 1,776 feet.
On Tuesday, the Council on Tall Buildings and Urban Habitat, an organization known as the world’s arbiter of skyscraper height, determined that the spire is part of the architectural design of the tower and should be counted toward its height, said Timothy Johnson, the council's chairman.
"We believe with certainty that the building is 1,776 feet tall, and the tallest in the country," Johnson said at a press conference Tuesday.
The spire's function as a broadcast antenna had thrown into question whether it should be counted toward the skyscraper's height — the council's committee of architects do not consider purely functional antennas in the official height calculation.
The spire at One World Trade Center was originally supposed to be encased in a fiberglass and steel covering, making it more clearly a continuation of the building’s design.
But since that design was scrapped, the spire had come under scrutiny.
Chicago's 1,450-foot Willis Tower, formerly known as the Sears Tower, actually has more stories than One WTC — 110 compared to One WTC's 104. Without the spire, One WTC would not have been tallest.
But Johnson said the council's panel of architects determined unanimously that the spire was indeed a permanent architectural feature of the building.
Especially when the spire was illuminated last week, it became even more apparent that the spire was a necessary feature of the building, he said.
One WTC's co-owners, the Port Authority and Durst Corporation, along with the architects of the building, Skidmore, Owings & Merrill, were pleased with the official height designation.
"This iconic building represents the resilience of America and today’s decision recognizes One World Trade Center’s rightful place in history," they said in a joint statement.