The Garden Shed and Agricultural Building at the 21 Acres Center showpieces a living roof system—rooftop gardens that support a responsible stormwater management system. When rain falls on open, undisturbed land, water goes through its natural cycle and returns to the atmosphere through plant evaporation and transpiration (or falls back into the water tables). However, when rain falls onto buildings with impervious surface cover, a staggering 75% of the rainwater becomes surface runoff which often drains into open water bodies, polluting them. By installing a Living Roof, we are able to mitigate the impact of our new construction on the surrounding land and reduce our future water use by 20-25%. The Living Roof will also provide an educational laboratory for the community to learn about the issues surrounding water reuse and conservation.

View roof construction video.

Basically a Living Roof (technical sketch) or a green roof as they’re sometimes called, are vegetated roof covers, with growing media and plants taking the place of bare membrane, gravel, shingles or tiles. The number of layers and the layer placement very from system to system and living roof type, but at the very least all living roofs include a single to multi-ply waterproofing layer, drainage, growing media and the plants, covering the entire roof surface.

Living Roofs are created with the beauty and anticipation of the changes of seasons with a wide variety of plantings. Sedums and other succulents, flowering herbs, grasses and mosses are used in a virtual living carpet or tapestry varying from season to season as plant communities naturally migrate in their random regenerative patterns.

Benefits of a Living Roof:

•    Improved Air Quality - filtrations of airborne particles and carbon dioxide/oxygen exchange
•    Temperature Regulation – moderation of the “Urban Heat Island Effect” (the difference in temp. between city and surrounding countryside)
•    Building insulation - industrial cooling and creation of microclimates
•    Water – stormwater retention, water filtration and reduced run-off
•    Social – aesthetics, health and horticultural therapy, improved safety, recreation and community building
•    Preservation of Habitat & Biodiversity – recreation of endangered ecosystems and habitats
•    Local Food Production – new opportunities for urban agriculture
•    Economic - increased job opportunities and community cost savings

http://www.greenroofs.com/