ORONTO, ON – May 27, 2009 – Green Roofs for Healthy Cities, (GRHC) the North American green roof industry association, is pleased to announce that the City of Toronto passed a new green roof by-law with overwhelming support yesterday. The green roof by-law consists of a green roof construction standard and a mandatory requirement for green roofs on all classes of new buildings. The by-law requires up to 50 per cent green roof coverage on multi-unit residential dwellings over six storeys, schools, non-profit housing, commercial and industrial buildings. Larger residential projects require greater green roof coverage, ranging anywhere from 20 to 50 per cent of the roof area.