By Julie Shapiro
LOWER MANHATTAN — While it may be hot on the streets of lower Manhattan, it’s even hotter on the black tar roof of the Department of Buildings headquaters at 280 Broadway.
Buildings Commissioner Robert LiMandri set out to change that Wednesday morning, as he and his staff coated the roof of the seven-story building in a reflective white sealant. The special paint is designed to bounce the sun’s rays and reduce energy costs.
“If enough people do it, we’ll actually make a big difference,” LiMandri said when he took a break from painting the 22,500-square-foot roof.
In neighborhoods with lots of tar roofs, such as lower Manhattan, Long Island City and Greenpoint, the reflective paint could even reduce the temperature down on the street, LiMandri said.
The sealant costs 30 to 40 cents per square foot, and it could cut air-conditioning costs in half for single-story houses with flat roofs. Two-story houses could see a 25 percent reduction in cooling costs. The sealant also protects roofs and helps them last longer.
One downside of the reflective paint is that it slightly increases a building's heating cost in the winter, compared to a standard black tar roof. But that increase in cost is easily offset by the savings on air conditioning in the summer, a DOB spokeswoman said.
The city hopes to have 1 million square feet of rooftops coated by this fall.
For more information or to participate, visit nyc.gov/coolroofs.