anyone heard of green roofs? ran across it by accident. Seems that in big cities in the US it is being established to lower the overall heat of the city. They basically cover the whole roof with growbeds and grow all kinds of plants. The roof is protected by acid and plants naturally filter carbon dioxide from the air and other pollutants. An interesting effect is a 26% drop in heating and cooling requirements of the buildings. This could be great, put your growbeds on top of your house for leafy crops and have all that area for harvesting. JUst wondered if this has been tried as this is the first I've heard about it. Course, I just found out about aquaponics and its been around years.