http://www.dailykos.com/story/...

French environmentalists succeed in getting a law requiring green roofs on commercial buildings. (or solar panels).

That's pretty cool! Wish the US was as forward-thinking.

Yeah. And we can't even get our water right!
But it would be neat to have a living lavender roof.

The lavender roof does sound dreamy. Bet the inhabitants would sleep well.
I wonder if I should give up trying to keep moss off of my roof shingles?

moss on shingles sounds like a leak down the road. I wonder how they make the green roofs so they don't damage the structure.

I've just seen bits on tv about green roofs and I would guess that the asphalt shingles would have to come off, a water-proof membrane installed (maybe like the ice shield stuff we use here) and then some kind of shallow, lightweight grid system to keep growing medium from washing away. Yeah, we do have to get rid of the moss on our shingles every couple of years. We've thought about installing copper strips on the roof but have never actually done it.