According to, “Green roofs will benefit wildlife more than traditional roofing methods.” The city of Toronto has taken this research and put it into practice. Toronto is now a leader in green roof policies. In 2009, Toronto became the first city in the world to enact a green roof bylaw. The City of Toronto Act (COTA) gave the City Council authority to pass a bylaw requiring and governing the construction of green roofs. As a supplement to the bylaw, Toronto offers an eco-roof incentive program.

According to the City of Toronto, the bylaw “applies to new commercial, institutional and many residential development applications.”  Up to 50% of the roof may be required to be green for multi-unit, residential dwellings over six stories, schools, non-profit housing, commercial and industrial buildings. According to Shayna Stott, Environmental Planner for the City of Toronto, the eco-roof incentive grants program gives financial incentives to those that are not mandated under the bylaw, such as owners of existing buildings. These programs together help the city meet the goals of its City’s Climate Change Action Plan.

There are four main components of Toronto’s Green Roof Strategy including,

  1. Installation of green roofs on city buildings
  2. Pilot incentive program to encourage green roof construction
  3. Use of the development approval process to encourage green roofs
  4. Publicity and education

Green roofs have many environmental benefits, such as helping absorb excess stormwater, increase energy efficiency, filter air, and beautify our cities.  One of green roofs’ most interesting characteristics is that they have the potential to increase biodiversity.

The City of Toronto defines biodiversity as “the complex, interconnected community of living organisms in an ecosystem.” One of its goals with this policy was that it could begin to connect natural habitats across the city. The report on Migratory Birds in the City of Toronto completed by Dougan and Associates and Environmental Inc in 2008 determined that “an ecosystem’s capacity to support a particular level of biodiversity is dependent on several factors. Climatic phenomena, such as the amount of incident solar radiation, seasonal variations and amounts of precipitation are all variable depending on the location of the ecosystem.”

Stott believes that Toronto’s Green Roof ByLaw has been successful and states that the standards are very tangible and can be designed to fit any need. When asked about her advice for other cities interested in enacting such a bylaw, Stott recommends starting off with solid research, so that you can truly understand the costs and benefits. This is critical to understanding where exceptions to the policy might be necessary. She also recommends starting off with a voluntary approach. Lastly, she suggests that you ensure that your locality allocates enough resources to educate the public.

In addition to Toronto’s Green Roof ByLaw, Toronto has Comprehensive Green Building Requirements for New Buildings, an office for Climate Change and Mitigation, and has been working towards increasing urban forests.

Toronto’s Green Roof ByLaw is an excellent example of how the process is as important as the outcome. Having public participation and buy in is critical in the success of any biophilic policy.

Carla Jones, Biophilic Cities Researcher

Carla is a dual candidate for Masters in Urban and Environmental Planning and Masters in Public Health at the University of Virginia.