“Toronto has been aggressive about it: they have a new, comprehensive green roof law, the first one in North America.
Efforts are already paying off: Green Roofs for Healthy Cities is reporting that the law has resulted in more than 1.2 million square feet of new green space planned on new commercial, institutional, and multi-unit residential developments. It will also keep enough rainwater runoff out of the lakes and rivers to fill fifty Olympic sized swimming pools. It’s reduced the heat island effect and led to an annual energy savings of over 1.5 million KWH for building owners…
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