In the increasingly urgent fight against climate change, simple solutions can have the most immediate impact. As a growing number of New Yorkers are finding out, one of the simplest -- and most effective -- is white roofs.
Just by coating black tar roofs across the city with a white, solar-reflective coating, we can immediately reduce temperatures inside and out -- making white roofs a quick and easy way to cut carbon emissions and reduce our risk of 'brown-outs' while saving millions in energy costs.
The concept is basic: dark colors absorb heat and light colors reflect it. The reflective properties of a white roof substantially lower the amount of heat absorbed by a building, keeping it about 10 degrees cooler inside and reducing summer energy use by 10 to 15 percent. (In the winter, when we want our buildings naturally warmer, black tar roofs have a negligible effect.)
White roofs, like green roofs, also reduce the "heat island" effect, in which temperatures rise in dense urban areas because of the proliferation of heat-radiating, black tar surfaces. That alone causes New York City to be about 5 degrees warmer than surrounding areas and accounts for 5 to 10 percent of summer electricity use. Coating all eligible dark rooftops in New York with a white reflective coating could reduce the air temperature of the city by a full degree.
Multiply this effort and the results are even more astonishing. If the world's 100 largest cities switched to white roofs, and to cement pavement instead of asphalt, it would be like taking every car in the world off the road for 11 years. It's the reason the Obama administration is touting white roofs as an effective way to slow climate change.
And New Yorkers are catching on.
The City, through its Cool Roofs project formed last year, set a goal of 1 million square feet of white roofs by next month. To help meet that target, grass-roots groups like the White Roof Project (the first non-profit established by the Manhattan Young Democrats) have sprung up to identify black rooftops, to assemble volunteers and to serve as a gateway for individuals to donate to the cause.
Just this weekend, White Roof Project volunteers teamed up with members of the Sierra Club and White Tops NYC to paint the 10,000 square feet of roofs at the Bowery Mission.
To add institutional support to this grass-roots movement, I am introducing legislation to align the Building Code mandate for cool roofs with LEED standards.
The incentives are in place for building owners (lower energy bills), volunteers (cleaner air) and, soon, developers. Now, we must build on our momentum to secure sufficient funding and people power to make our city a little bit less of a blacktop jungle.
Going green means going white, and by coming together we can all contribute to a cleaner, cooler New York.
Learn more, identify a black roof, donate or volunteer by visiting the White Roof Project at www.whiteroofproject.com.
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