Green roofs found to keep houses warm in winter

While much research has been done on how well vegetative roofs provide insulation in warm climates, new research has analyzed their performance in the cold of winter.
Brad Bass of the University of Toronto Centre for Environment analyzed a test “green” roof built in Ottawa by Karen Liu of the National Research Council’s Institute for Research in Construction. The test roof uses juniper evergreens and a thicker soil base than the typical leafy green roofs.
It was installed on a standard test house and on an energy-efficient winterized house. Indoor temperature fluctuations were tested in both houses to calculate energy savings. The results for the winterized house were “good,” while the results for the regular house were “dramatic.”
The results are been displayed on a poster as part of an exhibition entitled “Design for the Cold” at the Toronto Design Exchange, 234 Bay Street.
Funds for the project came from Environment Canada, NRC, the University of Toronto, and others.