Changes

#Modular system: green roof component layers are fused together as a moveable modular block system that can be linked together with other green roof blocks to form the green roof. This type of system typically forms an extensive green roof type and are used where roofs are sloped and flat.

#Modular system: green roof component layers are fused together as a moveable modular block system that can be linked together with other green roof blocks to form the green roof. This type of system typically forms an extensive green roof type and are used where roofs are sloped and flat.

#Layered system: all components' layers are loose laid as individual layers. This type of system can form both extensive and intensive green roofs and used typically on flat roofs.

#Layered system: all components' layers are loose laid as individual layers. This type of system can form both extensive and intensive green roofs and used typically on flat roofs.

[[File:Green Roof Shed.JPG|400px|thumb|right|Modular green roof system]]

[[File:Green Roof Shed.JPG|400px|thumb|right|Modular green roof system]]

=Component description=

=Component description=

[[File:Layers green roof.PNG|thumb|left|250px|Generalized cross-section view of a green roof showing key components and common layers that make up this LID BMP (TRCA, 2018)<ref name="example1" />]]

[[File:Layers green roof.PNG|thumb|left|200px|Generalized cross-section view of a green roof showing key components and common layers that make up this LID BMP (TRCA, 2018)<ref name="example1" />]]

*Vegetation free zone: separates the green roof perimeter from the roof perimeter and other structures on the roof (e.g., vents), that is kept devoid of vegetation and natural debris.

*Vegetation free zone: separates the green roof perimeter from the roof perimeter and other structures on the roof (e.g., vents), that is kept devoid of vegetation and natural debris.

*Root barrier: often a clear plastic sheet, the root barrier layer protects the water-proofing membrane from root penetration and degradation by microbial activity.

*Root barrier: often a clear plastic sheet, the root barrier layer protects the water-proofing membrane from root penetration and degradation by microbial activity.

*Leak detection system (if applicable): leak detection systems should be used to periodically check for the presence of leaks in the water-proofing membrane. See the page on [[Green roofs|green roofs]] for additional information on leak detection systems.

*Leak detection system (if applicable): leak detection systems should be used to periodically check for the presence of leaks in the water-proofing membrane. See the page on [[Green roofs|green roofs]] for additional information on leak detection systems.

[[File:Toronto City Hall Podium green roof by LiveRoof, July 2010.jpg|400px|thumb|right|Toronto_City_Hall_Podium_green_roof_by_LiveRoof,_July_2010]]

[[File:Toronto City Hall Podium green roof by LiveRoof, July 2010.jpg|400px|thumb|right|Toronto_City_Hall_Podium_green_roof_by_LiveRoof,_July_2010]]

=Key construction steps=

=Key construction steps=