Green roofs are great! They help alleviate a lot of issues that arise in urban living while making cities more beautiful. There is growing interest in making sure that urban green roofs take off and it looks like it is working.
While other countries like Germany have been using green roofs since the 1980’s, North America has been playing catch up. Toronto, however, is a city enamoured with renewable energy and sustainability. Ryerson’s engineering building on Church St., the new Forensic Services and Coroner’s Complex and Toronto City Hall are all notable examples of green roof early adopters.
A pioneer in North America, the city requires all new builds with a minimum gross floor area of 2,000m2 to include a portion of vegetation on roof surfaces. It also offers a grant of up to $75/square metre to offset the cost of green-roof installation. Similar incentive programs are being instated in Washington DC, NYC and Chicago, but Toronto is the first to actually mandate builders to include a vegetated roof – or face a hefty fine.
And with good reason. Green roofs divert waste, help manage storm water, moderate ‘urban heat island’ effects and improve air quality. They also reduce noise and can save significant amounts of money. In a warehouse complex, for example, the evaporation characteristics of a green roof can lower the inside temperature from between three to five degrees celsius.