News Releases - Government of Canada Reveals Major Greenhouse Gas Reductions and Air Quality Benefits from Widespread Use of 'GreenRoofs'

October 9, 2002 — Ottawa, Ontario

City of Toronto Deputy Mayor Case Ootes, as well as public and industry delegates today gathered at Toronto City Hall for a demonstration of the National Research Council (NRC)-led green roof initiative and to announce findings of a major study completed by Environment Canada indicating how green roofs can save millions of dollars in energy consumption, improve air quality and reduce greenhouse gas (GHG) emissions.

The Green Roof Infrastructure Demonstration Project is a $1 million public-private partnership between NRC's Institute for Research in Construction (NRC-IRC), Environment Canada, Green Roofs for Healthy Cities, the City of Toronto, the Toronto Atmospheric Fund and the Technology Early Action Measures component of the Government of Canada's Climate Change Action Fund.

The project consists of planting vegetation on building rooftops using infrastructure technology such as highly water-and-root-repellant membranes. NRC has instrumented the roofing systems and will monitor their performance over the next two years. These systems are located on two green roof sites, the publicly accessible City Hall podium roof and the recently completed Eastview Neighbourhood Community Centre, in Toronto.

"NRC's green roof infrastructure research initiative demonstrates the Government of Canada's commitment to innovation and the development of sustainable, healthy and economically competitive cities, and to improving the quality of life in Canadian communities through investments in environmental technologies," said Allan Rock, Industry Minister and Minister responsible for the National Research Council.

Findings from an Environment Canada study show green roofs can help Torontonians save energy, reduce greenhouse gas emissions, reduce emissions of sulphur dioxide and breathe easier on hot summer days. Toronto's summer temperatures are 4oC to 10oC higher than those in the surrounding rural communities, a phenomenon known as the urban heat island effect. This means that more energy is consumed to cool buildings, leading to more air pollution, in the form of smog and sulphur dioxide, as well as more greenhouse gases. The study illustrates that relatively minimal green roof implementation, approximately 6% of the total available roof space, can reduce summer air temperatures in the City of Toronto by 1-2oC.

"Environment Canada's study shows that green roofs can contribute to a reduction of energy use, which in turn helps reduce the emission of greenhouse gases and air pollutants. We are happy to be involved in the research and thinking for innovative ways of dealing with climate change and clean air," said the Honourable David Anderson, Minister of the Environment. "The Government of Canada not only supports this initiative, but we are acting on it with the construction of Canada's new War Museum in Ottawa which will feature a green roof."

Even a 1oC reduction in the urban heat island will result in a 5% decrease in demand for electricity for cooling and refrigeration, resulting in lower greenhouse gas emissions. Combined with direct energy savings on buildings, green roofs can save an estimated $1 million in energy costs per year, reduce GHG emissions by an estimated 2.18 MT based on 6.5 km2 of green roof coverage, and remove 30 metric tonnes of pollutants from the air. The reductions are measured in CO2.

"When it comes to climate change, innovative thinking and programs are key," said Herb Dhaliwal, Minister of Natural Resources Canada. "Projects such as this clearly show that we can address climate change while making our cities more liveable."

"Green roofs can help Toronto manage projected future population growth by creating accessible green spaces from existing roof tops," said Case Ootes, City of Toronto Deputy Mayor. "Green roof investment and incentives will also generate jobs, here in Toronto, while reducing air pollution."

"Green roof infrastructure investment addresses many key challenges facing cities across North America such as how to grow our cities up rather than sprawling to accommodate new growth and still maintain a very high quality of life," said Steven Peck, Executive Director, Green Roofs for Healthy Cities. "This research will help us to develop appropriate public incentives to encourage widespread private sector green roof installation and build a green roof industry in Canada."

Modern green roofs are an extension of the roofing system that can be designed to support different vegetation. The system involves growing plants on the top of built structures, below, at or above grade using a combination of plants, light weight engineered growing media, filter cloths, drainage layers and highly water-and-root repellant membranes. The project allows researchers to monitor storm water retention, energy efficiency and roof membrane durability. There are also plans to use these data to model the storm water benefits of green roofs later this year, in partnership with the Toronto and Region Conservation Authority.

This initiative builds upon the Government of Canada's commitment to ensuring a clean, healthy environment and preserving our natural spaces, which are essential elements of our quality of life.

For additional information, such as the project background and technical data, please visit the project Website at www.greenroofs.ca, or contact:

Nathalie Gour
Media Relations
National Research Council
Tel: (613) 990-6091
Cell: (613) 293-6617
e-mail: media@nrc-cnrc.gc.ca

Selena Beattie
Media Relations
Office of Minister Allan Rock
Tel: (613) 995-9001

Kelly Morgan
Environment Canada
Tel: (819) 997-1441
e-mail: Kelly.Morgan@ec.gc.ca

Steven Peck
P&Amp;A-Green Roofs for Healthy Cities-Canadian
Eco-Industrial Network
Tel: (416) 971-4494
e-mail: speck@mail.passport.ca

Jim Kamstra, Project Co-Chair
Facilities and Real Estate
City of Toronto
Tel: (416) 392-8954

Heather Bala
Natural Resources Canada
Tel: (613) 996-7252