Photo Credit Susanne Jespersen
Mountain Equipment Co-op or MEC, is a popular outdoor gear company in Canada. They are true pioneers in green rooftop installation. Seen here is the roof of a MEC store in Toronto. All the plants are native to Canada and are suited for prairie conditions. They have created prairie environments on many of their outlets, including the award-winning Winnipeg and Montreal locations. These green roofs are carefully planned ecosystems which, once established, sustain themselves as they would in the countryside. The one in Toronto covers an area of almost 10,000 sq.f., which means that over half of the entire surface is covered in shrubs, perennial grasses, flowers, herbs, and groundcovers.
A green roof must fend off the dual threats of root damage and water damage. Under the soil are hidden three layers: a barrier that prevents roots from growing into the concrete, but allows excess water trickle through, a drainage layer, and, just on top of the concrete, an insulation layer.
More photos of the MEC building.
See also Tour Green Toronto.