Canada’s largest city, Toronto, has become the first city in North America to mandate residential, commercial, and institutional buildings that are over 2,000 square meters (21,527.8 square feet) to have between 20 to 60 percent green roofs.
Green roofs, which are also known as living roofs, are not new, and have actually appeared in other cities such as Chicago and New York City where their use has made a positive impact. Chicago’s City Hall building has a green roof, and other buildings do as well in the city. New York City’s Con Edison Learning Centre also has a green roof, which saw savings in both the winter and the summer in terms of energy cost.
Aside from being aesthetically pleasing to the human eye, green roofs have proven to be beneficial for the environment: regulation of city temperatures, reduction of heat loss in the winter, reduction of heat gain in the summer, clean the air, cleanse water, and create living space for birds.
Savings in energy are not the only financial benefits of green roofs; there is also an increase in real estate property value but this has yet to manifest into a popular form of redevelopment for high-rises. The results from Toronto’s new law could influence other major cities across the continent, especially New York City and Chicago.
The bill is popular with residents but not with all building owners. Some have expressed opposition to the legislation as back as 2009 when it was first considered because it would penalize owners for not constructing green roofs when they do not consider it realistic to implement due to availability of space on narrow buildings.
The law will go in effect on April 30th.