Architectural Technology
CADD26909 - Architectural Drafting 3- CAD

Green Roofs

Green Roofs is a very old technology dating back centuries that is being used in many buildings today.

A green roof is a roof of a building that is partially or completely covered by vegetation, a growing medium and a waterproof membrane. This can be used to help with water runoff by absorbing rainwater and making drainage less chaotic, conservation (providing a habitat for wildlife), and probably the most important reason: insulation.

Green roofs act as a thermal barrier and greatly reduce the temperature of the urban area, helping reduce the heat island effect common in most cities today. Most cities encourage the use of green roofs, and some,like the City of Toronto, mandate their use on buildings larger than a certain size.

Traditionally, Green Roofs come in two main categories:

Extensive:

A roof covered in a light layer of vegetation that mainly consists of hardy plant varieties, such as sedum. These types of roofs require very little maintenance (some need no maintenance at all), are typically thin and lightweight.

Intensive:

A type of green roof that is thicker and can support a wide variety of plants, including trees. This is almost like having a garden on the roof and it requires a lot more maintenance than extensive roofs.

The roof on the Arvid warehouse is an extensive green roof.

The City of Toronto has a Green Roofs website. You will find Guidelines for Biodiverse green roofs, a link to the Eco-Roof Incentive program and more.

The City of Toronto's "What is a green roof" page is a very informative page with a lot of data on different types of green roofs. Some of the images in the article can be seen in Google Earth (these are links to Google Earth kmz files):

• Manulife Centre Garage - 44 Charles St. West, Toronto (Intensive roof)
   
• Mountain Equipment Co-op - (Extensive roof)
   
• New green roof on the old York University Computer Science Building (Extensive roof)
   
• ESRI Canada (Retrofit intensive green roof)

Other Links to green roofs:

LEED and green roofs

Wikipedia - Green Roofs

Chicage City Hall green roof

Tokyo Imperial Hotel - Green roof and solar panels (Google Earth kmz link)

Mississauga Transit Maintenance Terminal (pre-cultivated vegetation blanket)

University of Toronto Mississauga Campus

National Geographic has a fantastic slideshow of green roofs

Green city in lower Manhattan, New York (Intensive roof)

Developers blue over green roofs: An article from the Globe and Mail.