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945-ft ‘Glass’ Skyscraper May End Up Greenest of Them All
Tower shaped by columns that slope in one direction and in principal planes.
For several months in 2008—until the World Trade Center’s 1,776-ft-tall Freedom Tower is finished—a planned 945-ft-tall Manhattan skyscraper might rank second in height in New York City to the 1,250-ft Empire State Building. But forget stature. The team for One Bryant Park, just starting construction, is far more excited about how “green” it might be.

As planned, the 2.1-million-sq-ft office tower will have all the usual bells and whistles of a high-performance skyscraper and then some. A proposed anaerobic digester plant to produce methane from food waste and a “green” roof may not materialize. But the building is on course to have a 4.5-MW cogeneration plant; night ice production; rain, stormand groundwater capture and use for heating and cooling; underfloor air distribution and more. The features could slice $3 million per year off energy bills.

With an air-handling system that filters 95% of particulates, this building is going to clean up the city’s air, says Robert F. Fox, principal of the project’s local Cook+Fox Architects. And it will have no stormwater discharge to the city. The plan is to capture 4 ft of annual rainwater expected to fall on the two-acre site.

In spite of all-glass facade, annual energy bills are expected to be $3 million less. Steel frame will precede core construction.

Scott Frank, associate partner for the building’s local consulting engineer, Jaros, Baum and Bolles, calls the water conservation measures “unique” to a tall building. Tanks for the water-capture-and-reuse system will be on different floors of the building, utilizing gravity feed and minimizing pumping, he says. The team is even seeking city approval for waterless urinals. That would save 3 million gal of water per year, says Frank.

The 51-story building, with a seven-story podium that extends beyond the tower’s 40,000-sq-ft footprint, is shaped like a giant crystal, with origami-like folds in its all-glass facade that create facets. Offices will have 9.5-ft ceilings within a 14.5-ft floor-to-floor height, which includes raised floors. The southeast face will have a double glass wall to vent solar heat gain out the top.

The building has a structural steel perimeter frame and a structural concrete core. The facade folds resulted in only one totally vertical perimeter column, says Edward M. DePaola, principal in charge for the local structural engineer, Severud Associates. All others slope at different elevations. The complexity of the sloped surface is minimized by columns that slope in one direction and only in principal planes, says the engineer.

Unlike most New York City high-rises, the steel will lead core construction. This strategy was developed by Severud in the 1970s, but never implemented in New York until recently, says DePaola.

The construction manager selected the approach because frame construction is about one-third quicker, says Joseph L. Ross, executive vice president of Tishman Construction Corp. of New York. Tishman also is using the approach on Seven WTC and says the strategy relies on the use of climbing forms, which allow the core to keep pace with the steel.

Bank of America, which is the co-developer with the local Durst Organization, will occupy about half the building. Durst is the owner of the neighboring Four Times Square, considered the nation’s first “green” speculative office tower when it opened in 1999.

Fox, who was also the architect for Four Times Square, says One Bryant Park could not have happened without its neighbor. But One Bryant Park “is a dream project” by comparison because it has the commitment of not just the developer, but also the main tenant, he says.


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