Landscaped Rooftops Save on Energy Bills

Landscaped Rooftops Save on Energy Bills

Alexandria, VA - Roofs are now going green and taking our nation by storm.  Many building owners and homeowners are replacing standard roof shingles with vegetation in order to reduce their carbon footprint and enjoy significant savings in their heating and cooling bills.  Vegetated green roofs offer many earth conscious advantages. 

A roof is considered “green” when covered with soil and vegetation.  Although the concept of green roofs has been around for centuries, they’re growing in their popularity in our green world.  Consider its advantages – energy reduction, reduced storm water runoff, reduced heat island effect, increased habitat area, extended roof life and let’s not forget its sheer beauty.   A standard dark colored roof’s temperature is about 175°F compared to a living roof where the temperature reduces to a mere 95°F.  This drastic reduction in the roof temperature can ultimately reduce heating costs up to 25% and cooling costs up to 50%.

In the past, green roofs have been primarily constructed on flat rooftops often in urban environments.  Gravity, vertical wind uplift and erosion problems prevented building owners with sloped or pitched roofs from installing a green roof.  Recently, a resident in Alexandria, VA approached Capitol Green Roofs for a living roof on their recent addition.  The challenge presented to Greg from Capitol Green Roofs was their uniquely designed arched roof.  Greg teamed up with Cell-Tek Geosynthetics from Crofton, MD, who manufactures a recycled stabilizer grid system designed specifically for this application.  “There are various challenges when dealing with a sloped or pitched roof.” says Gregory Long, Design Director at Capitol Green Roofs.  “Cell-Tek’s System solved my concerns with soil migration and wind erosion.  It even allowed me to ensure an even coverage of soil throughout the roof,” says Long.

The contractor who installed the green roof removed the existing shingles on the addition and laid down a rubber waterproofing membrane to protect the roof and prevent any water leakage into the house.  The next layer was a geo-textile drainage mat followed by the Cell-Tek 3” depth cellular confinement system.  The system is then secured to the roof by tendons to prevent any slippage.  Afterwards, the cells were filled with topsoil.  The finishing touch was a pre-vegetated sedum mat and the end result was a beautiful living roof for this homeowner.