Site Size, Zoning Influence Tower Design

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A new 748 ft tall twisting tower accommodates two hotels—one on top of another—in New York City’s crowded theater district.
March 11, 2014—In late 2013, two new hotels opened in New York City’s theater district in Manhattan. The hotels are located on the same site and are stacked one on top of the other—resulting in a 748 ft tall tower. Twisting as it ascends skyward, the tower’s design was specifically crafted to fit within the small size of the site while meeting city zoning code restrictions.
The skyscraper houses two Marriott properties—a 261-room Residence Inn by Marriott and a 378-room Courtyard by Marriott—in its 68 above-grade and two below-grade floors. The first through third floors are public areas for the Residence Inn, the fourth floor is a public area for the Courtyard, and the fifth floor houses a bar and lounge for both hotels. Above that, the 6th through 33rd floors are designated to the Courtyard, while the 37th through 68th floors accommodate the Residence Inn. A shared health club is located on the floors between the two hotels, while the building’s two below-ground levels house a conference center and support facilities, also for both hotels.
G Holdings LLC, a privately held New York City-based development and property management firm led by chief executive officer and chairman Harry Gross, owns the tower. The firm held an informal design competition and as a result of that process, selected Nobutaka Ashihara Architect, PC, headquartered in New York City, to design the project. The architects were challenged with designing an approximately 400,000 sq ft building on a site that occupies just 10,000 sq ft. Achieving the desired square footage required a tall tower. “It is a very small site, but they wanted to build a building with enough area for a more than 600-room hotel,” says Nobutaka Ashihara, AIA, the president of Nobutaka Ashihara Architect. “To achieve that, the building is [nearly] 40 times the site area.”
The tower is located at 1717 Broadway, overlooking Times Square. At the corner of Broadway and 54th Street, the site is part of a city zoning area known as the Special Midtown District, which limits how much of the sky a building is permitted to block from ground-level view and the amount of shadow it is allowed to cast. The tower’s twisted form is designed to meet those restrictions. “The first component of our building is the first floor to fifth floor, then above that is one hotel, above that is another hotel, and above that is a five- to six-story high cube,” Ashihara explains. “Each element is not lining up with the other; it’s almost rotating or twisting. That gives you a very unique architectural expression and reduces the amount of the shadow, as required by the zoning requirement.” 
The tower’s twisting shape and glass facade limit the amount of shadow the building casts on the streets below
The tower’s twisting shape and glass facade limit the amount of
shadow the building casts on the streets below, a requirement of
the city’s zoning codes. Nobutaka Ashihara Architect, PC
Most buildings in New York City occupy just 10 to 15 times their footprint area, so constructing one that is 37 times its land area is quite unusual, Ashihara says. Despite zoning restrictions, the team was able to provide so much floor area by relying on a part of the New York City building code that allows developers to purchase and transfer development rights from low-rise buildings to high-rise projects. “We used a technique called an ‘air-rights transfer,’ meaning that if there is leftover space next door, you can actually buy that and then that area can be applied to our site,” Ashihara explains. “At this particular location …there are lots of one-story tall Broadway theaters, so there is leftover building area above them. And within this particular zoning district, you can actually transfer the remaining air right space from faraway places, not just next door. That’s how we achieved the huge area.”
Although the designers weren’t striving to obtain the title, the tower is the tallest hotel-only building in the North America. Because of its height and relative thinness, a wind tunnel test revealed that the tower initially swayed significantly under wind loads. A large water tank was incorporated into the cube at the top of the tower to reduce the swaying. “By putting this huge water tank on top of the building, if the building sways toward the right, the water is going to go left, so they compensate for each other,” Ashihara explains. The other benefit of the water tower is that if the building ever catches fire, the water can be used to help put out the flames. “Many projects don’t use water to stabilize a building, but the reason we are interested in the water is, God forbid, if somebody set fire to something, we can just dump all of the water from the top,” Ashihara notes.
The tower is framed in reinforced concrete. To increase its structural stability, the tower’s columns, shear walls, and central core are connected by outriggers, which are located at the top of each of the two hotel towers. Each outrigger is approximately one floor high, so the building’s mechanical systems are situated at those locations. Ashihara says, “This building is very tall and slender, but by tying the structural elements together, you increase the strength and stability of the building.” The New York-based structural office of WSP Global, Inc., an international engineering firm headquartered in Montreal, Quebec, Canada, served as the structural engineer on the project.
The tower is clad in energy-efficient, double-glazed glass and each hotel room has a floor-to-ceiling window. The glass affords views to Times Square and nearby Central Park, and helps reduce the amount of shadow the building casts on the surrounding streets. But despite the tower’s glass facade and prominent location, it is designed to be private enough to provide respite from the bustling city streets, Ashihara says. “We were challenged with designing an extremely private space in the middle of an extremely public area,” he says. “For our hotel, the transition from the public to the private is carefully coordinated so people will feel very comfortable.”
The $319-million tower officially opened at the end of December 2013. Ashihara says he hopes people who visit the hotels find them safe, secure, and serene and enjoy their central location in the heart of New York City’s theater district. “If people will actually enjoy the private space, that is the basic goal of our design,” he says.

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