Established in 2010 on the roof of the John H. Daniels Faculty of Architecture, Landscape, and Design at 230 College Street in Toronto, the Green Roof Innovation Testing Laboratory (GRIT Lab) is a state-of-the-art facility — and the only one of its kind testing the environmental performance associated with green roofs, green walls and solar photovoltaic technologies in Canada. A second site is currently being established on the roof of the Daniels Faculty's new building at 1 Spadina Crescent.

To date, GRIT Lab includes 33 green roof test beds, 3 green walls, a weather station, and 270 sensors connected to over 5,000 linear feet of wiring. Data on soil moisture, flow rates, temperature, rainfall, humidity, solar, and wind is collected every 5 minutes. The integration of real-time data monitoring to study the metrics associated with ‘green’ and ‘clean’ technologies provides a comprehensive and dynamic understanding of the water-energy-biology nexus in context of regional and climate specific priorities.

Phase I (2010-2016) has been designed to test and evaluate green roof construction standards specifically in context of the City of Toronto’s Green Roof Bylaw Construction Standard and with respect to four primary environmental criteria: 1) Stormwater Retention, 2) Evaporative Cooling, 3) Biodiversity, 4) Life Cycle Cost. A 350 sq.m section of the Daniels Faculty roof has been dedicated to conducting the experimental aspect of this research. Thirty-three beds have been designed to compare the following four parameters: 1) growing media type, 2) growing media depth, 3) vegetation community, and 4) irrigation regimes. Each bed is instrumented with thermal and moisture sensors, a rain gauge and infrared radiometer; the data will be analyzed against base-climate data, acquired via a weather station onsite. Phase I also includes a study of green facades and their influence on the thermal regulation of a building envelope.

Phase II (2013-2016) will focus on evaluating the synergistic relationship between green roofs and PV arrays. The hypothesis is that green roofs reduce local air temperature through evapotranspiration and solar reflectance and that this improves PV performance and lifetime. The integration of PV with green roofs is important because it will contribute to reducing environmental impacts by simultaneously designing for renewable energy, evaporative cooling, and stormwater retention on building rooftops. Phase II will include a 150 sq.m area of the Daniels Faculty roof. In Phase II, 2 different PV module heights – 60cm, 120cm (2, 4ft) will be tested above 2 roofing surfaces – white and green for optimal PV performance, exposure to wind, practicality of installation and maintenance, and effect of shading of plants.

GRIT Lab provides a platform for multi-disciplinary research and education by linking the fields of Landscape Architecture, Biology, Hydrology and Building Science. Its wide range of partnerships with industry, academic institutions and government agencies have far reaching implications for education and knowledge transfer, innovation and commercialization, as well as policy and guidelines. As such, students are offered a unique hands-on opportunity to work directly with the latest material and digital technologies, as well as with both industry experts and academics from a wide range of disciplines. The cross-pollination among various disciplines is intended to generate new ideas, while the link to industry facilitates their implementation.

GRIT Lab is led by professors Liat Margolis (Landscape Architecture), Robert Wright (Landscape Architecture), Dr. Ted Kesik (Building Science), Dr. Brent Sleep and Jennifer Drake (Civil Engineering).

The research undertaken by GRIT Lab was made possible through grants from the City of Toronto, Ontario Centres of Excellence, RCI Foundation, the Connaught Fund and the Landscape Architecture Canada Foundation, as well as the generous support of the University of Toronto and industry partners Bioroof, Carl-Stahl-Decorcable, DH Water Management, Greenscreen, IRC Building Sciences Group, Scott Torrance Landscape Architect, Siplast, Schletter, Sky Solar, Toro, Tremco Roofing.