Why Green Roofs Have the Power to Reduce Flooding in Cities
Sourced from the Weather Network
Imagine a garden on your roof: plants growing, trees thriving, and, most importantly, excess water absorbed by nature rather than inundating your basement. The concept of a “green roof” has come to life in many cities across North America. Not only are they a stunning scene but also a solution to urban flooding.
“A green roof is a system that you apply to a waterproof roof which allows you to safely and securely grow plants,” explained Steven Peck, Founder of Green Roofs for Healthy Cities.
“The technology typically involves several different layers, including a root repellent layer to protect the waterproofing, a drainage layer that allows excess rainwater from leaving the roof through drains, a filter cloth which prevents the clogging of the drainage layer, engineered growing media (not soil) which is light weight, drains well and provides nutrients and anchorage for plants, and, of course, plants themselves, which range from small succulents to trees.”
You may not have realized, but in Toronto alone there are 900 green roofs! They cover more than 8.5 million square feet of roof space, which is about 95 football fields. In 2009 Toronto was the first city in North America to implement a green roof bylaw, which required buildings and additions over a certain size to dedicate a percentage of the available roof space to green roofs.
From the Living Architecture Monitor
