green roofs

On June 25, 2008, the New York State legislature passed a bill allowing building owners in New York City who install green roofs on at least 50 percent of available rooftop space to apply for a one-year property tax credit of up to $100,000. The bill is expected to be signed by Governor David Paterson shortly.

The credit would be equal to $4.50 per square-foot of roof area that is planted with vegetation, or approximately 25 percent of the typical costs associated with the materials, labor, installation and design of the green roof. Building owners will be able to apply for the credit starting Jan. 1, 2009.

A 10,000-square-foot green roof can capture between 6,000 and 12,000 gallons of water in each storm event. In addition, the evaporation of this rainfall will produce the equivalent of between a 1,000 and 2,000 tons of air conditioning, enough heat removal to cool 10 acres of the city.  This energy cooling could save New York City residents more than $5 million annually. In addition to reducing greenhouse gas emissions, green roofs will also help reduce overflows of raw sewage into area waterways. The tax credit starts Jan. 1, 2009, and will expire after March 15, 2013 unless extended.

Other cities have passed similar laws and green roofs are sprouting up all over, including Chicago's City Hall.  Could this be the beginning of a trend?    

We already blogged the winners of last week's Solar Decathlon in Washington, DC on our front page. However, I just wanted to take a second to point everyone towards a very interesting and very related post over at EcoGeek. The post is "Green Roofs? How About Green Walls!"

EcoGeek offers links to a number of Solar Decathlon teams that incorporated green walls into their contest entry houses, and he argues that green walls might be the next big green thing because of the insulation potential and their ability to mitigate stormwater runoff.

Check it out!