We've always loved a house with a green roof. It's one of the must-have features for our dream house. Or it was until today when we had a conversation with an architect that gave us pause. We learned that there's one major thing to consider in making the decision between a green roof and a solar roof. Can you guess what it is? If you said "location," you are right on the money. When comparing the economic and environmental issues of both roofs, it's important to look at the whole package. Green roofs insulate, yes, but they also need water to maintain them properly. They work best in climates, like that found in Seattle or San Francisco, which see a fair amount of rain. In these places, they'll work to their best advantage, preventing run-off, keeping your home cool in the summer and warm in the winter and you won't have to water them very often. Solar roofs, on the other hand, work in harmony with the environment of places like Los Angeles or Phoenix, where rain is scarce but sun is plentiful. In a sunny climate, they'll work to generate enough electricity to not only heat the water and power your appliances, but to support wonderful amenities like radiant heat floors (another feature on our list) should the weather turn chilly.