Green roofs (also called eco-roofs) are roofs that have soil and living plants covering their surface. Green roofs have been popular in Europe (particularly Germany) for the past 20 years. They are gaining acceptance in the United States.

Green roofs have many benefits including increased roof life, lower energy costs, improved roof runoff water quality, and reduced stormwater detention storage. They are an important component of sustainability.

Green roof buildings are specially designed and built to handle heavier roof loads than conventional buildings. The roofs have additional structural support plus a vapor control layer, thermal insulation, and a waterproof membrane between soil and roof. In addition there is a drainage layer under the soil to remove excess water. Specific vegetation that thrives in a thin soil and dry summer conditions is used. The vegetation transpires stormwater back into the atmosphere.

For more information, try these websites:

Northwest EcoBuilding Guild

Hadj Design