More on green roofing

In class Evan referred to this article by NYT columnist Verlyn Klinkenborg on green roofing in the May 2009 issue of National Geographic. A quote: "While the average cost of installing a green roof can run two or three times more than a conventional roof, it's likely to be cheaper in the long run, thanks largely to energy savings. Vegetation also shields the roof from ultraviolet radiation, extending its life. And it requires a different kind of care, akin to low-maintenance gardening....The goal for some researchers now is to find ways to build living roofs that are ecologically and socially sound in every respect: low in environmental costs and available to as many people as possible." Sure sounds cool, doesn't it?