Which Is Greener, White Roofs or Green Roofs?
In this article for Sourceable.net, I looked into the environmental benefits of white roofs compared to green, or living roofs, as stated in a new report by the Lawrence Berkeley National Laboratory. It turns out that white roofs are most cost effective overall, and most effective at mitigating climate change by reflecting heat back into the atmosphere.
Green roofs, however, offer other benefits, and last roughly twice as long as white roofs or traditional black roofs. Green roofs of living plants can absorb pollutants such as particulate matter, sulfur dioxide, carbon monoxide, and nitrogen oxides. Green roofs also produce oxygen, consume carbon dioxide, and help to manage stormwater and runoff. Over their lifespan, green roofs are not necessarily substantially more expensive than white roofs.