Green Roof Systems, Precious Technology

     In this blog I want to give some general information about Green Roofs and their considerable effect on reducing the energy consumption of buildings in Green Building industry. As we know, using green roofs in our structures has some positive effects on it such as reducing storm water runoff, attenuating roof temperature, reducing heat island effect, optimizing energy performance, etc. Nowadays, green roofs are going to be more widely used in different structures, but still it has to be improved in different aspects. (e.g. 20% of commercial roofs in Germany are green.)

     Although it seems that green roof construction need a set of skills and takes a lot of time, effort and money (comparing to conventional roof construction), It can considerably reduce the amount of energy usage in a building. Generally, green roofs are made of some typical layers such as waterproofing membrane, insulation, protection fabric, drainage and filter layers, soil media and vegetation. The typical layering of the green roof systems can be seen in the picture below. Also, beside reducing the Heat Island effect, this system can effectively be used for reducing of the water consumption of a building as well.

     As some of the good examples of green roof users in United states, I should mention Ford Motor Company (Dearborn, Michigan), Ballard Library in Seattle, the new California Academy of Sciences building (Golden Gate park, San Francisco), United States Postal Service's Morgan Processing and distribution Center (New York City), Zeckendorf Towers (New York City), etc which are shown in the pictures below.

Ford Motor Company (Dearborn, Michigan)

Billard Library, Seattle

New California Academy of Sciences building (Golden Gate park, San Francisco)

United States Postal Service's Morgan Processing and distribution Center (New York City)

Zeckendorf Towers (New York City)

     Using this technology in the state of Florida has some issues such as intense rainfall, long drought conditions, hurricanes, wind uplift and scour resistance, viability of plants, biodiversity, fire resistance concerns, etc. After a lot of investigations in this field, researchers came to that the cultivation of Florida green roof must take some points into consideration such as heat flow, moisture residence, plant selection, depth of roots, weed suppression and wind uplift. Among these, wind uplift seemed to more critical in using green roofs which some useful researches had been done for obtaining better criteria in use of green roofs considering the wind uplift issue (“Wind resistance of green roof systems” David Prevatt, Glenn Acomb). Here, I should mention the Perry construction yard green roof on top of the Rinker school of building construction at the University of Florida, which was used as a case study for this research.

Rinker school of building construction, University of Florida

     In conclusion, I think although cultivation of green roofs in Florida has some issues, it can be really helpful for structures in this region to be more sustainable. Investing time and effort in researching in new ways of using this industry can lead us to a more sustainable future. Tough, there are a lot of new research topics in this field that should be taken into consideration.

The Importance of Being Sustainable

          Have you ever been thinking about the relationship between you and the environment around you? How much do you care about your natural habitat? Do you consider your life style to be environmentally friendly? Do we think about the future of our planet when we are spending its natural resources? Surely, many of us have been encountered to these kind of questions nowadays. But why do we have to find an answer for them? The answer is "Energy". As we know, our planet is functioning with all kinds of energy transformation each day. In a more precise view, every individual need energy to sustain his daily life. But how should we share these finite sources of energy to assure that all of us have the ability to sustain? Regarding to a well-known article named "The tragedy of the commons" by Garrett Hardin, population naturally tends to grow exponentially and the "tragedy" occurs when individuals and the society are locked into a system that rationally forces them to maximize his gain by taking without limit, in a world that is limited. So, how can we survive?

            The answer that is given to this question is being more sustainable. Regarding to the definition given in the world commission on environment and development report "Our Common Future"(1987), sustainability is meeting the needs of the present without compromising the ability of the future generations to meet their own demands. Lets be more familiar with this concept. A few months ago, I took an on-line "Carbon Footprint Assessment" survey. Carbon Footprint, as Wiedmann said, is “a measure of the exclusive total amount of carbon dioxide emissions that is directly and indirectly caused by an activity or is accumulated over the life stages of a product”. After completion of this survey I found that my carbon footprint on the environment is almost 2.7 times bigger than the average footprint for people in United States which was embarrassing and really surprised me. Then I found that it was because of the long-distance travel that I had taken from my country which is almost 8000 miles far from here. So I decided to calculate my carbon footprint in a two-week period in my home country before coming here. In the second assessment my footprint was calculated as 1.3 times larger than the average footprint for people in Iran.

My Carbon Footprint in a two-week period in the United States / Iran (Left side / Right side)

Although I think by increasing the time period to a year, the results would be less, the amount of carbon dioxide emitted from my normal activities in my life style is larger than the average. However, I think that my life style is normal and almost every individual around me has the same style and that’s the tragedy. Before this survey I thought that I might be normal but now I have to think about the correction of my style of living.

There are some practical ways that I can reduce my carbon footprint. First of all, I can reduce it by accommodating the use of residential energies in my home. It doesn’t mean that I have to decrease the use of energy. It would be just correcting the way of using the energy resources. The second way is to use public transportation instead of driving my own car which can be easily done. It needs just a little thinking about the terrible effect that I am going to put on the environment in my lifetime. After these, I can try to change my food preferences, garment preferences and many other aspects of my life style. Also Recycling plays an important role in this promotion.

           In a Nutshell, individuals must take the correction of their life styles into consideration immediately. To make a conclusion, I should mention the Matthew R. Simmons’s speech in the "Limits to Growth" article which is “It is time for the world to re-read Limits to Growth! The message of 1972 is far more real and relevant in 2004 and we wasted a valuable 30 years of action plans by misreading the message of the first book."