Read: Christian Werthmann - Green Roof: A Case Study

Why didn't I read this book while I was still in Washington? It's a case study of the green roof installed at the American Society of Landscape Architects headquarters in Washington DC several years ago. If I'd known about it, I could have visited it! Ah well. The book gives a good details on how the roof came to be and what all the different considerations were that went into making the final decisions. I went on their website after to look up information on how the roof is doing now, four years after publication of the book - looks like the plants have filled in nicely.