The greening of roofs is nothing new. Northern Scandinavia and Germany have practised this for more than a hundred years. However, today preferring green roofs to conventional alternatives is becoming more common in countries such as Australia, Canada, Greece and the US. In April this year France passed a new law, mandating that all new buildings in the country’s commercial zones must be partially covered in either plants or solar panels.
A green roof or a living roof is defined as the roof of a building partially or completely covered with vegetation, planted over a waterproofing membrane. This includes additional layers such as root barriers and drainage and irrigation systems. Green roofs also indicate use of some form of green technology, such as a cool roofs or solar panels. However, the notion of container gardens or vegetation in pots as green roofs is still under debate.
Green roofs offer several benefits such as absorbing rainwater, providing insulation, creating a habitat for wildlife and de-stressing people with an aesthetically pleasing landscape. They also help to lower urban air temperatures and to mitigate the heat island effect. Other benefits include filtering pollutants, insulating buildings for sound and increasing agricultural spaces to promote biodiversity and reduce emissions.
Whether beautifying Boston bus-shelters or providing a sky garden of wild flowers on top of a UK salad factory, green roofs lead to not only healthier cities but more scenic and soothing ones, too.