BIG adds a pair of twisted travertine towers along the High Line

Bjarke Ingels Group (BIG) has completed One High Line, a pair of twisting, travertine-clad towers in Chelsea. Named for their proximity to the High Line, the buildings house luxury condominiums and a hotel. To maintain sightlines from the High Line to the Hudson River, the facades of the two towers are angled away from each other at their base.

One High Line broke ground in 2016 and was initially known as “The XI.” In 2021, the project’s original developer, HFZ Capital Group, foreclosed on the project, temporarily halting construction on the towers, which had reached their tallest height at the time.

The project was eventually rescued by Witkoff and Access Industries and completed earlier this year. The new developers opted for a name change but kept the overall design.

Before construction could even begin, intensive work was required on site to get the project off the ground. First, the site, which had previously served as a car park, had to be extensively rehabilitated as it was considered a brownfield site from previous industrial use.

In addition, the foundations of the towers were built on virgin land that was once part of the Hudson River, requiring deep-drilled piles to reach bedrock through layers of rubble. Due to the construction project’s proximity to the High Line, the construction team also had to shore up the foundations of the elevated park.

Building regulations required the architects to design the towers over a podium at ground level. The courtyard in the middle of the podium was used to create a vestibule. In addition to the lobby and living areas, the podium also houses rentable office floors.

Since the site extends below the High Line, the developer has created space for a small park at the other end of the elevated train tracks.

The zoning plans also determined the height of each tower, so the west tower is 402 feet tall and the east tower is 302 feet tall. The east tower houses the hotel and residences, while the west tower is exclusively condominiums.

The towers of One High Line are in many ways an homage to two skyscrapers designed by Gordon Bunschaft – the WR Grace Building across from Bryant Park and the Solow Building on West 57th Street. In addition to the curved geometry – which all three buildings share – Bjarke Ingels was inspired by Bunschaft’s use of travertine. In particular, One High Line echoes the contrast between dark, rectangular windows and white travertine of the WR Grace Building.

In a nod to Chelsea’s industrial past, One High Line’s windows feature relief patterns that allude to similar details in nearby warehouses.

The distinctive, winding shape of the towers is structurally less complicated than it appears, and was achieved by arranging sloping elevations supported by stepped columns.

“Most of the columns are about a foot high to match the slope of the building,” said Beat Schenck, partner at BIG. “Almost half of the column rests on the column below.”

In rare cases where the slope of the building was too great and the columns did not overlap, inclined columns were used to compensate for the difference.

In a nod to Chelsea’s industrial past, One High Line’s windows feature relief patterns that allude to similar details in nearby warehouses.

Instead of using a crane to lift the glazing into place – as would be common when installing curtain walls – construction workers were able to install the windows from the inside of the building.

“As soon as the superstructure is finished, these openings can be framed. Then the window fitters take all the elements to the floor using the elevator and install them one by one,” said Andreas Buettner, an employee at BIG. “They didn’t have to use a crane at the top. This was a very efficient way to close the floors as quickly as possible.”

The travertine slabs were later installed using mass climbers – movable platforms that climbed the outside of the buildings.

One High Line took a long time. Chronologically, the project is BIG‘It is the second building in New York City – after VIA 57 West – but has been surpassed by the completion of other works, such as The Spiral, a supertall glass tower that opened last year.

“The project was on hold for quite some time – obviously‘s has never preferred to expose a construction site to the elements,” said Buettner. “When the second owners were ready to leave, we had to do a lot of mediation to get it back to its original state… It was great that the client took that on and kept the vision alive.”

Project specifications