For the next three and a half months, the Toronto Transit Commission will use “sound cannons” on the rooftop of Leslie Barns in effort to stop seagulls from nesting and returning to the building.

Blue and green roofs can help combat urban challenges such as stormwater runoff and heat islands and are a small but growing market for geosynthetics.

including a rooftop garden. The property is a partnership between the centre, the City of Toronto and the federal government through the Canada Mortgage and Housing Corporation. Strejko has lived ...