World Trade Center, 15 Years Later

Structural steel for the 80-story 3 WTC office tower is scheduled to top out in early October; the building will be completed in 2018. (3 WTC construction photos: AISC)

Fifteen years after the September 11 attacks, NYC’s World Trade Center site has been rebuilt, structure by structure. The first tower to open at the 16-acre site was the 72-story 4 WTC, followed by the 104-floor 1 WTC, the National September 11 Memorial and Museum and the WTC Transportation Hub, which officially opened to the public in March. For more on these steel-framed projects, see the MSC articles “Four at the Fore” (04/2015), “Rising to the Top” (02/2014), “Trident True” (01/2014) and our previous post on the Transportation Hub.

The next tower to open at the World Trade Center site will be 3 WTC, which is scheduled to top out in early October and will be completed in 2018. The 80-story office tower is planned to be about 1,080 ft tall, which will make it the third tallest of the site’s skyscrapers after towers 1 and 2. Owen Steel Company (an AISC member and certified fabricator) fabricated 27,000 tons of structural steel for the tower’s gravity system, which has few interior columns and no perimeter columns, giving tenants ample space and unobstructed views. The building also features a three-story lobby that contains a retail complex with architecturally exposed structural steel (AESS) and a connection to the nearby Transportation Hub.

Plans for a fourth skyscraper, 2 WTC, include an 80-plus story tower, which will be the second-tallest of the site’s skyscrapers. It is being designed as seven separate building volumes stacked on top of each other, built with a concrete core and an external structural steel frame.

For more about the WTC site, visit