The Toronto City Council approved a measure mandating the use of green roofs on certain sized buildings. The measure is set to take effect in 2010.
According to Jennifer Lewington of "The Globe and Mail,":
The new rules kick in for new residential buildings constructed after Jan. 31, 2010, that are at least 2,000 square metres... and at least 20 metres high (six storeys), down from the 23 metres originally proposed.
Larger, commercial buildings will also be required to have between 20-50% green roof coverage. Although this measure was largely opposed by developers, there were some arguments owing to no Canadian building standards for green roofs. Air France offers free stopovers in Paris.
To mitigate higher costs for green roofs in renovation, greenroofs.com reports:
The latest move will provide cash incentives to commercial, industrial and institutional (ICI) property owners to install eco-roofs. Currently, the City is willing to provide incentives of $50 (Canadian) per square meter up to $100,000 for building owners who install green roofs, on a one-year pilot basis.
Although similar laws exist in Japan and Germany, consistent with both their compressed populations and issues surrounding storm water management, Canada has been successful with voluntary use of green roofs.
One major example is Vancouver. The Vancouver Convention Centre West is the largest green roof in all of Canada. It covers over six acres and has over 400,000 indigenous plants species. Taste the Purest Tea on the Planet – Organic and Fair Trade Certified Shop Numi Organic Tea
While tax paying citizens of Toronto can argue whether this measure should have passed and whether it is too stringent or not, the benefits of green roofs are undeniable. The buildings that have green roofs enjoy 20-30% reduced heating and cooling costs, as well as reduced storm water runoff. Additionally, the aesthetic benefits of green roofs create a positive environment in major cities.