Green Roofs….Why not?

Green roofs have started to become really popular overseas, specifically in countries such as Germany, France, Austria, and Switzerland. I live in America and have started to question why I am not seeing green roofs all over the place. Green roofs do come at a higher initial price point than most building or people would like to spend, but in the long term they can add many benefits to your wallet as well as eye.

What is a green roof? The fact that we barely use this technology on this side of the pond means you and I probably have a vague understanding on what a green roof is and what the use of them means for us in the long run. A green roof can be defined by the extension of ones roof to house a multitude of natural elements by incorporating water-proofing, filter cloth, drainage systems, root repellent systems, a light weight growing medium, and plants. So far you have two options when installing a green roof, either modular or loose laid/build up. A modular system is created offsite and installed in a grid-like system. A loose laid/buildup is the installation of all necessary materials directly on the roof, essentially integrating the green roof into the structure itself.
There are many benefits when looking at a green roof as an option for your roof top space. They do look good, you’re not only making your roof space more appealing to you, but you are making your area more appealing to everyone around you. Utilizing green roofs can contribute to landfill diversion by increasing the life of the actual waterproof membrane (reducing plastic consumption), using recycled materials in the substrate, as well as prolonging the service life of heating, ventilation, and HVAC systems due to the fact that they will be used a considerable amount less.

Green roofs also aid in storm water management as well as moderate the urban heat island effect. Plants need water and for a green roof that water is stored in the medium. During the heat of the summer the green roof can hold 70-90% of precipitation that makes contact, and 25-40% of contact precipitation during the winter months. The fact that these roofs can hold so much water equates to a decreased stress on sewer systems during heavy rains and a lower possibility of erosion surrounding the building its self as there is less roof runoff. While in-taking as much water as possible from Mother Nature green roofs also displace heat and help cool urban centers. Black rooftops are some of the hottest surfaces in the urban environment and using a green roof is a great way to mitigate the heat for you as well as your neighbors.

Plants do provide us with air to breathe and also filter out many contaminants/pollutants that we produce daily, which does help our air quality. Many cities are getting bigger and bigger, with that we see higher concentrations of pollution and a greater need for a solution. There will never be a one-size fits all fix for the damage that we are doing to the environment, but the use of green roofs can offset some of the negative effects of our modern way of living.

So you have installed a green roof, how is that going to affect your building and your life? The green roof acts as a large dense piece of insulation, which is going to keep your home/building cool in the summer as well as keep the heat inside during the winter. The National Research Council of Canada conducted a study on green roofs and found that the use of green roofs can reduce the energy demand for air conditioning by up to 75% during the summer months. Structures with green roofs dampen many noises from the outside world. An extensive green roof can reduce sound from the outside by up to forty decibels, and an intensive green roof can lower sound by forty six to fifty decibels.

Green roofs can have a great impact on your space, they can save you money, make your building look better, increase the value of your structure, make your space visibly appealing, and actually be a benefit to the natural world around you. As we have begun to destroy landscapes for urban development, we will probably begin to see a growing trend of green roofs as we have stated to see a trend of green walls on the inside of buildings. A green wall could be just what your building needs, or could be an option for a future home. Green walls are being used more and more overseas, I can only hope that we take notice and begin to aid the environment as well as curb energy costs with European green roof technology.