Seen from above, the city’s panorama of grey roofs and concrete can be rather drab, but, for local company Native Roofs, there’s potential for green in all that grey.
Last February, Native Roofs, a subsidiary of environmental consulting company Applied Aquatic Research, started selling “green roofs,” rooftops covered by four to six inches of soil, grass and vegetation, to ecologically minded companies and individuals.
The company touts the many benefits of its system and speaks from experience; in 2007, it installed its own green roof and, according to operations and marketing manager Alex Court, has saved around $3,600 a year on energy bills alone. According to the National Research Council of Canada, green roofs have the potential to reduce heat loss by 10 to 30 per cent in colder months and heat flow by 70 to 90 per cent in the summer.
Green roofs boast other benefits, as well. “If you are under a flight path, there’s sound-insulation value,” says Court. “It also extends the lifespan of the roof; normally, for this building, you’d have to replace [the roof membrane] every 15 years. With a green roof, it extends to at least 40 years.”
The reason tufts of grass aren’t already poking out atop buildings across the city, says Court, is partly because of the difficulty of growing vegetation in Calgary’s climate. But, using native species like blue grama and Rocky Mountain fescue, as opposed to imported staples like Kentucky blue grass, Native Roofs recreates the ecosystem of living plants that would naturally occupy an area, making for a well-adapted, resilient roof.
Court points to Toronto, which mandates that certain new buildings have green roofs, as proof the concept can take hold and believes Calgarians are interested in growing their rooftops, as well.
“I think that we’re primed for it; I think that people want to see more of an environmental push,” says Court. “It’s not really the way we are in Calgary, but I think it’s in the air.”