Toronto First North American City to Require Green Roofs

thivest.com:

• by Cathryn Wellner

Toronto is making history. The first city in North American to require green roofs on new developments moves into the third phase of its Green Roof Bylaw on April 30, 2012.

Adopted in 2009, the bylaw required the environmentally friendly roofs on residential, commercial and institutional buildings starting in 2010. Now, with the addition of industrial developments, all new buildings with a minimum Gross Floor Area of 2,000 square meters will be required to devote 20-60 percent of Available Roof Space to vegetation.
Aside from the pollution-scrubbing gift of rooftop parks, the greenery pays off in lower utility bills. Two American green roofs give an idea of potential savings. The Chicago City Hall installed a green roof in 2000 and now saves $5,000 a year. New York’s Con Edison Green Roof absorbs 30 percent of the rainwater that falls on it. It also reduces heat loss by 34 percent in winter and heat gain by 84 percent in summer......  more