Toronto Puts Green Roofs Law for Industrial Buildings Into Effect April 30

March 30, 2012

Having a green, living roof is no longer simply a piece of philosophical green whimsy. On April 30 in Toronto, the Green Roof Bylaw will now expand to affect industrial buildings.

Under the Green Roof Bylaw, Toronto – always a leader in green activism – becomes the first city in North America to have a bylaw requiring the construction of green roofs on new developments. Toronto City Council adopted it in May 2009, under the authority of Section 108 of the City of Toronto Act.

The bylaw applies to new building permit applications for residential, commercial and institutional development made after January 31, 2010 and will apply to new industrial development as of April 30, 2012.

The green roof requirement is graduated, depending on the size of the building. The following table shows how the requirement ranges from 20-60 per cent of available roof space for commercial, institutional and residential development. This space is the total roof area minus areas designated for renewable energy, private terraces and residential outdoor amenity space. A tower roof on a building with a floor plate less than 750,000 square meters is also excluded from available roof space.

Gross Floor Area *
(Size of Building)

Coverage of Available Roof Space
(Size of Green Roof)

2,000 – 4,999 m2


5,000-9,999 m2


10,000-14,999 m2


15,000-19,999 m2


20,000 m2 or greater


 Energy bills and the global climate are far better off with such far-sighted legislation.

Photo: Small