What’s up with Green Roofs?

At last year’s official Green Building Council of South Africa (GBCSA) Convention and Exhibition in Cape Town, green roofs emerged as one of the ways to transform buildings in an environmentally sustainable way. Even though the concept of green roofs is relatively new in SA, these attractive features are being successfully integrated into buildings the world over. We chatted to one of the speakers, local horticulturist Zayaan Khan, about the significance of this new form of gardening and how to create one yourself…

What is a green roof and what different types are there?

There are many definitions as to what a green roof is, but simply put a green roof system is ‘an engineered roofing system that allows vegetation to grow on top of buildings, while protecting the integrity of the underlying structure.’ This description can be found in Green Roofs: Ecological Design and Construction by Earth Pledge.

There are two types of green roof systems: extensive or intensive.

Extensive green roofs are shallow and lightweight, and are conducive to growing heat-tolerant, low-growing plants. They are generally, although not always, inaccessible. That said, they require minimal maintenance and survive on rainwater – much like a naturally occurring system, they are left to their own devices.

Intensive green roofs have a deeper substrate which may accommodate flowering shrubs, vegetable production, trees, and even ponds. An intensive green roof is more intensive in maintenance, hence its name. It is also more interactive and accommodates the user, unlike an extensive green roof system. In intensive systems one would find bigger plants with a deeper root system, such as trees and larger shrubs, and even vegetable gardening which all require more in-depth planning and after care.

Read the full article at House and Leisure

Image courtesy of Carnotzet at flickr.com, and used under a Creative Commons licence (Attribution-NonCommercial-NoDerivs 2.0 Generic (CC BY-NC-ND 2.0))