Hardy alpine strawberries are a good choice for planting a green roof.

Green Roofs for Healthier Communities

by John Gillespie
Image © Christina Symons

Some well-known buildings like the Vancouver Public Library are renowned for cutting-edge architecture. But an innovative green roof technology was also successfully incorporated into the design. Did you know that the new justice building in Sechelt also incorporates an energy- and environmentally-beneficial green roof?

The traditional tile, shake, tin or tar roof is making way for a technically superior horticultural greenspace that promises to reduce our impact on the local environment and provide for increased roof lifespan and energy efficiency.

Historically, green roofs have been used for hundreds, if not thousands of years. Canada has had a Viking village built with turf roofs and numerous examples of dwellings that allowed early inhabitants to live comfortable lives in a very rugged environment. Most travellers to Vancouver Island remember the grass-covered market roof in Coombs that has a resident goat for added roadside appeal.

In Europe green roofs and other sustainable development technologies ave become commonly accepted features in the construction industry due to rising environmental concerns and the rapid decline of green space. With increasing levels of pollution many North American cities are endeavouring to take green roofing to the next level. These efforts will help efforts to reduce greenhouse gas emissions and move towards sustainable development by providing human and environmental health while yielding economic benefits.

Eventually, as each new building project sees the enormous possibilities of these initiatives, green roofs will become as common as in Europe and have a noticeable impact on the surrounding neighbourhood.

Green roofs involve the containment of green space on top of a human-made structure. An extension of the existing roof, involving a special root repelling membrane, drainage system, lightweight growing membrane and plants.

The point of the green roof is to make it green and efficient. They provide the owners of a building with a proven return on energy investment and significant social, economic and environmental benefits. Green roofs also simultaneously meet pressing concerns for smog, climate change, and stormwater management and energy conservation.

John Gillespie is Horticulturist and Arborist for the District of Sechelt. He writes regularly on gardening subjects for the Coast Reporter newspaper.