The 895 ft tall tower will taper in an east-west direction, creating the visual appearance of leaning toward the city. Rendering courtesy of MIR
The groundbreaking for a 47-story concrete, “angled” tower in Manhattan—part of the new 26-acre Hudson Yards development—took place in December.
January 8, 2013—A new 47-story, 1.8 million sq ft tower, boasting a 15-story-tall atrium located midway up its height, will join the Manhattan skyline by 2015. To be built entirely of concrete rather than of the city’s more typical steel, the building will be one of a pair of towers that appear to lean away from one another—one toward the Hudson River and one toward Manhattan. Tower C, the southernmost of these two commercial towers, is the first portion of the 26-acre Hudson Yards project—owned and operated by Related Companies and Oxford Properties Group, both of New York City—to break ground.
“Our inspiration for the Hudson Yards is wholly New York City,” said William Pedersen, FAIA, FAAR, a cofounder of Kohn Pedersen Fox Associates’ and the firm’s senior design partner, who wrote in response to written questions posed by Civil Engineering online. KPF is the architect for the overall Hudson Yards master plan, as well as the two angled towers and the podium.
“We sought to find a unique way to link the project to the surrounding city,” Pedersen said. “This was accomplished by creating two buildings in a geometric dialogue, which brings about a type of dance, gesturing to both the city and the river.”
The Hudson Yards development as a whole will be “a city within a city,” according to Pedersen. The unusually large development—for Manhattan—will include three additional mixed-use and residential towers, residential buildings, park space, and a public square. Much of the site currently comprises below-grade rail tracks, which will be covered over and transformed by the new development, according to the New York City Department of City Planning.
Tower C will be 895 ft tall, tapering in an east-west direction from approximately 225 ft at the base to 140 ft at the top, creating different floor areas at each level and the visual appearance of leaning toward the city. The exterior of the tower will boast floor-to-ceiling glass and two large outdoor terraces—one on the 32nd floor, and the other on the 47th floor.
Concrete is the building material of choice for the tower despite the fact that buildings in Manhattan are more typically built from steel, because of the “great efficiency” that it would bring to the tower, according to Joanna Rose, the vice president of Related Companies.
The tower will feature a cast-in-place concrete frame with a concrete core; large, flexible floor plates; and extensive column-free spaces, according to Aine M. Brazil, P.E., LEED AP, M.ASCE, the vice chairman of Thornton Tomasetti’s New York office, who wrote in response to written questions posed by Civil Engineering online. The floor framing will comprise one-way slabs spanning to posttensioned beams supported by lines of columns spaced 30 ft apart on center. Thornton Tomasetti is serving as the structural engineer for Tower C and for two glass-and-cable walls that form portions of the building’s skin.
The southern base of the tower will straddle a section of the park
created atop the city’s famed High Line. Rendering courtesy
The southern base of the tower will straddle a section of the city’s famed High Line park. (See “New York’s ‘High Line’ Railroad to Become an Elevated Park,” Civil Engineering, July 2006). A row of columns will extend unbraced 80 to 100 ft above the street level along the southern base of the tower, up to the 5th floor, allowing the High Line to pass beneath, Brazil said. A 200 by 80 ft cable wall and glass system will act as the building skin for the lobby, overlooking the High Line.
A large portion of the building is being leased by the global fashion firm Coach Inc., which will make the space its world headquarters. An internal atrium will visually tie together Coach’s headquarters by extending upward from the 6th floor to the 21st floor, encompassing the entire space being leased by the firm. The cable-and-glass façade at this location comprises 10 ft by 4 ft 6 in. glass panels spanning nearly 200 by 60 ft, “creating a dramatic portal overlooking the High Line and southern Manhattan,” Brazil said.
The glass panels will be supported by 1 5/8 in. diameter cables that will be pretensioned from trusses and concrete walls located at the 5th and 21st floors, according to Brazil. To reduce the required amount of pretensioning, architecturally expressed steel spandrels will be located at alternating floors, she noted. These will also provide pathways for the heating elements.
The foundations are typical large-capacity caissons weighing up to 7,500 tons, Brazil said. Piles will be used in some locations in which loads are lower, she noted.
The developer anticipates earning a gold certification from the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) program. A 1.2 MW cogeneration plant that will be a key component of the mechanical, electrical, and plumbing system will aid in this effort, Pedersen said.