Green roofs are literally as the name implies, roofs that are green with plant life that is planted on top of buildings. This practice allows for more vegetation to be installed while not interrupting urban infrastructure.
The plants have several uses on top of buildings. Environmentally, these plants will act as a carbon sink and also reduce the amount of runoff from rainwater. Also, the installation of green roofs will help to reduce urban temperatures while also acting as an insulator, preventing heat or coolness from leaving buildings.
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Other Sources
David Suzuki Foundation. “Green Roofing Options.” David Suzuki Foundation. http://www.davidsuzuki.org/what-you-can-do/queen-of-green/faqs/recycling/green-roofing-options/?gclid=Cj0KEQjw8pC9BRCqrq37zZil4a0BEiQAZO_zrG4MVD44euPaqRoUpWdMr-P-E6A81HEiwJUbnwMRR58aAuTL8P8HAQ. Accessed August 5, 2016.
Dowdey, Sarah. “What is a Green Roof?” How Stuff Works?. http://science.howstuffworks.com/environmental/green-science/green-rooftop.htm. Accessed August 5, 2016.