Toronto is set to implement a law that would make green roofs mandatory for tall buildings. Being Toronto, the policy is confused and is arguably not bold enough, but the fact that this is being tabled with support across the city is a very good sign. Torontoist author Toodd Aalgaard has a look at the green roofs coming to Toronto:

After January 30, 2010, according to a draft version [PDF] of the by-law being tossed around today, every building “with a gross floor area of 5,000 square metres or greater shall include a green roof,” meaning that rooftops greater than five thousand square metres in area will require 30% green coverage, with 60% for rooftops exceeding twenty thousand square metres. Further, the construction and maintenance of new roofing will toe strict guidelines laid out in the Green Roof Construction Standard [PDF], ranging from assembly and load bearing to fire safety and plant selection. Even minimal alterations will be subject to City approval.

The Globe and Mail also examines Toronto’s green roof law:

The proposed bylaw would mandate specially irrigated rooftop gardens that are said to reduce air-conditioning costs and mitigate the “urban heat island” effect blamed on pavement and dark roofs.

Part of Mayor David Miller’s climate-change initiative, the move was deferred for fine tuning yesterday and was to return to a meeting next month of the city’s planning and growth committee.