“When you find out Toronto overwhelmingly passed a by-law mandating green roofs on all classes of new buildings, your immediate reaction is to feel sorry for all the future orphans and quadrapalegics and mowing fatalities that will soon follow, but your fears are misplaced.
Toronto’s new green roof by-law, which passed in a 36-2 vote, sets up new construction standards requiring green roofs on all classes of new buildings, and 50% green roof covereage on multi-unit residences over six stories, shools, non-profit housing, commercial and industrial buldings. So while homeowners may be wary to wander on their new lawn, commercial spaces are blessed with reclaimed gardens and meeting spaces.
Green roofs require less maintenance than regular roofs, they reduce heating and cooling costs throughout the year, they provide sound-proofing, they help manage storm run-off, and they reclaim an otherwise unused space for aesthetic purposes for homeowners and businesses alike.
“Toronto’s by-law provides a new opportunity to strengthen the emerging practice of integrated green building design,” said, Steven W. Peck, President of Green Roofs for Healthy Cities. “The by-law breaks new ground on how to structure a mandatory green roof requirement and the construction standard also contains important best practices that may prove to be a model for other cities.””
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click the above image for more on Singapore’s Ecological EDITT Tower
Tribal Interloper 
And Planners by influencing legislation can make this happen.