Pemaquid Pond

Benefits of a Vegetated Roof

There’s a misconception out there that a vegetated roof requires a lot of maintenance. Who mows the grass? Who weeds the roof? Green roofs don’t work that way and don’t require that kind of maintenance. The goal of an ‘extensive’ green roof such as this is to simulate the conditions at the tops of Maine mountains where the soil is thin, fast-draining, but high in nutrients. Alpine sedums thrive in these conditions and little else does. Once the sedums take over, hardly anything else stands a chance at growing. This creates a naturalized environment for the plants that requires extremely little human interaction for maintenance. Within the first two years of planting, care should be given to the roof to make sure it doesn’t dry out (in case of a drought). But after that, it’s happily on its own.

Aside from looking beautiful, the benefits are that a vegetated roof has zero heat gain in the summer. As the plants respire they naturally keep the roof cool and shaded. The vegetated roof also naturally treats storm water, helps control erosion, and protects the membrane roof below increasing its longevity.