Quantitative evaluation of greenroof systems for sustainable development

Rooftop gardens or greenroofs provide multiple benefits in support of environmental sustainability such as improved stormwater management, improved air quality, increased energy efficiency, increased roof life cycle and decreased heat loading to the atmosphere contributing to the mitigation of the "Urban Heat Island Effect". The objective of this paper is to design an on-site evaluation for the quantitative benefits of the greenroof system. The study describes the design and data collection of six greenroof systems in the Greater Toronto, Area, to specifically quantify the multiple benefits of greenroofs in Canadian climate. The long-term, real-time monitoring program will help to define the ecological and hydraulic benefits of the greenroofs. The findings of this study will be used to support a region-wide database for the evaluation of the potential benefits of installing greenroofs on a broader scale and to support the implementation of new stormwater policies related to rooftop gardens for new installations or retrofitting applications.