Raising the (Green) Roof!!


Mountain Equipment Co-op Building, Green Roof. Copyright Terri Meyer Boake.

Last Saturday I attended a Green Roofs and Roof Gardens workshop hosted by Everdale Organic Farming & Environmental Learning Centre. Carolyn Moss, Principal Architect at Moss Sund Inc and Terry McGlade, Horticulturalist and President of Gardens in the Sky were our professors for the day spent at a public library in Toronto.

The room was packed with about 50 people from all walks of life; from architects to designers to home owners interested in greening their roofs. There was even a guy from La Garrotxa, outside of Barcelona, interested in doing a green roof. Lloyd told us about his involvement in a green roof exercise lead by Carolyn in 2005. She also mentioned the exercise in her presentation. What a small world...Carolyn also told me that she went to university with our head Treehugger, Graham Hill.
The day-long workshop began with Carolyn's presentation about the principles behind green roofs. Their history from the hanging gardens of Babylon, vernacular buildings in Europe, Viking and prairie sod houses in North America to ecohotels in Sri Lanka, The Ducks Unlimited Canada Headquarters and the upcoming Vancouver Exhibition Centre.

Logically we discussed the many benefits of green roofs and rooftop gardens such as cooling the building, reducing the urban heat island effect, protecting the "membrane" (aka roof), increased amenity space, promoting biodiversity, the potential for urban agriculture, stormwater management, noise reduction (they said noise can be reduced by up to 30 decibels!) and for businesses the obvious image improvement for marketing purposes. The list goes on and on.


Terry McGlade and Carolyn Moss at the workshop. Photo by Jenna.

Terry McGlade is one of the leaders of the green roof movement in Canada and has been instrumental in bringing green roof technology into its own. He continued the day with discussions focused more on plant types, medium options, soil types and drainage.

One of the highlights of the day was Terry's run through of a number of green roof and rooftop gardens that he has worked on. The list was impressive and the pictures were gorgeous. It was especially interesting to see the photos immediately after the installation and the photos from one or two years later.

Some of the commercial examples included:

180 Queen Street West, Toronto KPMB.

401 Richmond , Toronto.

Mountain Equipment Co-op Building, Toronto. (see first image and link to more images)

215 Spadina, Toronto — The Robertson Building (Image below from the Robertson Building website).

There was so much information packed into this day. For example, you can do green roofs on pitched/sloped roofs, but it's obviously more dangerous and you should really call in some expert "roof-walkers" to do it. Flat roofs are obviously easier to work with, depending on access. But the options are out there and they will always depend on the roof and amount of space you have to work with.

Prices have gone up since Lloyd participated in the workshop we mentioned earlier. It's approximately $15-25 per square foot to install these green house top covers, but Terri and Carolyn mentioned that you can't get a nice ceramic floor tile for that price. It's all relative. Definitely the residential examples we saw were of large homes. Ironically enough, the biggest homes are the ones that are getting the greenest roofs (like one worth $2.2 million that is now for sale complete with green roof). A bit of a paradox, but hey we should applaud them for doing it. Hopefully it will become so popular that it will be more accessible for people with average to lower incomes.

At the same time, as Terry explained, condo buildings aren't really viable when it comes to green roofs because they are too high up and it wouldn't be of any benefit. The wind and the temperature change every 6 stories, so the taller the building, the less likely your chances of having an effective rooftop garden.

He also mentioned incentives that have been offered by the City of Toronto to create green rooftops. Apparently they provided $5.00 per sq. foot subsidies, but this was based on a limited total budget of only $250,000. Terry repeatedly reminded Torontonians to write to their ombudsperson, city councillor or local politicians to push for more of this type of subsidy.

He also duly noted that the key to the green roof process or the most vital component is (of course) the plants. Knowing your plants and suitable plant types are key. It seems like the installation of the different mediums and even the all-in-one kits are pretty easy, but knowing what plants to put on your rooftop oasis is vital to a successful project.

This was a great-green day. I met some very interesting people, listened to two fabulous speakers and met Lynn — our wonderful host from Everdale. If you have the chance to see Terry or Carolyn in a workshop like this I would highly recommend it. Or if you are interested in other Everdale workshops, I can tell you that they are well worth the effort.

More info here on: Gardens in the Sky, Everdale and Moss Sund Inc.

Tags: Buildings | Canada | Gardening | Green Roofs | Toronto