Concrete isn't exactly a nice process on the environment. How and when should we use concrete? In the article its all about thermal mass and longevity. For design though there is more to design. Is there a way we can use concrete in new exciting ways, while still greening it up? Can we build concrete that decays? Maybe instead of looking at how long it can last, we should make it to last for less time. Allowing it to be looked at as a material instead of a timeline.