A new wave of green building is sweeping across commercial buildings and finding its way to neighborhoods world-wide—the green roof. I don't mean ecologically minded roofing materials, I mean a green roof. Roof experts are finding that planting a hardy sedum in a 2-4 inch bed of dirt atop special soil and root barriers creates a vegetated roof that benefits the building and the community. Suited only to roofs with under 5 percent slope, these extended green roofs help control heat loss and gain, reduce runoff, combat noise transfer inside the home, and reduce the impact of urban heat islands. These roofs are fire resistant and can actually prolong the life of the roof by protecting it from ongoing cycles of expansion and contraction as well as degrading UV rays. Energy savings with a green roof can be as much as 50 percent! Some question the stress that the plant bed will place on the roof structure, but the 4-inch module only adds 15 pounds per square foot when fully saturated. I can only imagine how much prettier the skyscape would be and how much more oxygen would circulate if green roofs sprang up in our urban centers. The cumulative energy savings are so great that there are even tax incentives being offered by some municipalities. Granted, if you have a traditional gabled roof, you're out of luck. But we can always spread the word to our flat-topped neighbors.