But Gedge also believes that support from local government, as opposed to a centrally driven policy, is key to the industry's growth.

CNN: Green roofs cool cities, combat climate change, say Germans

Dusty Gedge, co-founder of Livingroof.org, a UK Web site promoting the green roof industry, believes it is the government's responsibility to help the industry grow.

CNN: Green roofs cool cities, combat climate change, say Germans

" Green roofs also struggle against better-known technologies such as solar panels, but Gedge points out, "Solar panels can work better on green roofs than on gray roofs.

CNN: Green roofs cool cities, combat climate change, say Germans