The cost of the under-construction One World Trade Center in New York, US could top $3.8bn, which would make it the most expensive office tower in the world, according to reports.
One World Trade Center, designed by Chicago-based Skidmore, Owings and Merrill has seen its initial estimated costs rise by around $700m, according to the latest public figures.
The rise in the estimate is due to cost overruns for the construction and a decision by the Port Authority of New York and New Jersey (PANYNJ), which owns One World Trade Center to include leasing expenses in its public estimates.
Additional security costs associated with the construction of the tower has also added to the cost as the site was the target of major terrorist attacks in 1993 and 2001.
The entire project includes the construction of two buildings, rights for two more towers, a memorial and museum, and a $3.4bn transportation hub primarily funded by PANYNJ through toll money from airports, bridges and tunnels.
The One World Trade Center skyscraper, originally named the Freedom Tower, is being built on the same site where the World Trade Center towers were destroyed by a terrorist attack on 11 September 2001.
One World Trade Center is being built by PANYNJ, which owns the 16-acre World Trade Center site in consultation with structural engineer WSP Cantor Seinuk.
Upon completion, the 1,776ft tower will be the tallest in the US, built upon a heavily reinforced, windowless podium with a thick core of concrete and steel around its elevator shafts.
The completed tower will house 2.6 million ft² of office space, a two-storey observation deck, skyline restaurant, retail spaces, broadcast and antenna masts and four floors for below street-level parking.
Construction of One World Trade Center has reached 90 stories while 4 World Trade Center, a 72-storey office tower being built by private developer Larry Silverstein, has reached 61 stories.
One World Trade Center is expected to be completed at the end of 2013.
Image: The tower will house 2.6 million ft² of office space, a two-storey observation deck, skyline restaurant, retail spaces, broadcast and antenna masts and four floors for below street-level parking. Photo: The Port Authority of New York.