News, September 11, 2006, NYC: A Green Roof Grows in Long Island City

Silvercup Studios is most famously home to Tony Soprano; since last July the former bakery, located next to the Queensboro Bridge, also became the site of New York’s largest green roof. In 2002 landscape architect Diana Balmori conducted a study of the city’s rooftops to identify the best area where green-roof construction could have an impact not just on an individual building but an entire neighborhood. The study revealed that Long Island City would be the most promising neighborhood for clustering these environmentally friendly roofs, which help clean the air, reduce storm-water runoff, lower energy consumption, and ultimately reduce the heat caused by urban congestion.

There is enough suitable flat roof space in Long Island City to cover more than 26 million square feet with green-roof technology—or 667 acres, nearly the size of Central Park. Known as pancake roofs, the countless flat-topped warehouses were mostly built before 1955, when structures were generally overengineered; therefore they can withstand rooftop vegetation without additional support.
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The green-roof system on Silvercup is a modular one built by GreenTech, a company based in Roswell, Georgia, which donated a third of the modules for the project. Unlike plantings directly on the roof—a more common type of green-roof system—the interlocking modules can be moved and replaced (see “Green How-To” on page 100). Covering 35,000 square feet required 1,500 modules filled with a lightweight soil and then planted with 20 different varieties of sedum. Sedum is heat and drought resistant because it retains a high percentage of water in its shallow root system. Therefore it absorbs and holds more rainwater, reducing storm-water runoff and minimizing landscaping maintenance. Irrigation is needed to get the plants established, but they eventually become self-sustaining.
- View From the Bridge, Lisa Chamberlain, Metropolis Magazine