The Importance of Being Green: Green Roofs Help Urban Inhabitants Breathe Easier

 

 

Rachel Eckenreiter, Animal Science

Justin Esiason, Environmental Science

Patrick Meehan, Building Construction Technology

 

     As the sun rises in Beijing, the workforce can be seen flowing into the arteries of the city to start the day. The streets steadily fill with people, some whizzing by on bicycles, others on foot as the sun fights through toxic haze and dust. A father and daughter navigate through the dense crowd, completely unfamiliar with the language spoken around them and written on street signs, the young girl quickly glances around her, confused and overwhelmed. Faces of many sizes, ages and shapes glide by, most clad in white medical masks. Her eye catches something they’ve seen before: the welcoming sign of their hotel.  The bright and quiet lobby is cool and clean as they head toward the elevator. Once in the room, she wastes no time and heads straight for the bathroom sink, with the sensation that her face is covered in grime as if she had worked in a dry dirt field all day. After washing her face, she glances down to find that the pristine white hand towel had turned mostly dark grey and brown. Although their stay in China was only three weeks long, it was enough time to recognize that the city of Beijing had a major air pollution problem. (Rachel Eckenreiter, Personal Communication, April 6, 2017).   As time marched on in this bustling burhal, it began to appear as if smog was draped like a grey veil over the entire city.  These opaque conditions made it almost impossible to see beyond 100 yards. Citizens began wearing surgical masks to protect themselves from the harsh environment around them. Schools were forced to close their doors and construction was halted throughout the city. News channels encouraged their viewers to stay inside and the government set traffic regulations. In an attempt to reduce smog, Beijing ordered their first red alert and required half of all cars to stay off the roads (BBC, 2015). The life flowing through the ever moving metropolis of Beijing was arrested, as it’s people hid in their homes from the horrors of air pollution.

These record breaking pollution levels are arising all over the globe and without immediate intervention will continue to pose detrimental effects on urban lifestyles (WHO, 2016). This is the reality of each day for people in Beijing, Kuala Lumpur, Mexico City, Los Angeles, Fairbanks–the list goes on. The United Nations said in their 2014 World Urbanization Prospects report that 54% of the world’s population lives in urban areas. Global consensus agrees that airborne particulates cause health problems for humans (Pope, Thun, Namboodiri, Dockery, Evans, Speizer & Heath, 1995). By this reasoning alone, most humans on Earth should be concerned about air pollution and looking for ways to reduce it. Furthermore, urban air pollution drifts throughout the atmosphere (Friedlander, 1977)–thus, those in rural areas should be concerned with this as well.
    Particulate matter smaller than about 2.5 micrometers (PM2.5) across are able to penetrate to the deepest part of the lungs (EPA, 2008).

In addition to having adverse effects on our atmosphere and environment, Carbon dioxide (CO2) has the potential to cause a variety of health issues for humans (Rice 2004, para 1.).Carbon dioxide is a “major greenhouse gas” that is released into the atmosphere through various human activities and natural process (GSA, 2011.). CO2 is known to have numerous effects on human health, ranging from physiological impairments to long term respiratory infections. When studying this matter it is important to understand both the short term (acute) complications that come with CO2 intake, along with the long term and prolonged effects that it may have. Acute carbon dioxide intake poses problems varying from chronic headaches to sudden attacks of vertigo (Rice 2004, para 1.). Long term, prolonged effects of excess carbon dioxide expose include alterations in bone metabolism and blood calcium percentages (Rice 2004, page 6.).It is also important to consider the amount of carbon dioxide being exposed when identifying underlying issues. Increased exposure to high quantities of carbon dioxide is stated to have a range of effect on the human body and brain. High-level exposure of CO2 can result in poor memory and the inability to concentrate along with difficulty sleeping and other visual field defects, including an enlargement of blind spots (Rice 2004, page 6.). Furthermore, research has found a direct correlation between excess carbon dioxide exposure and human cognition and thinking abilities (Allen, MacNaughton, Satish, Santanam, Vallarino, & Spengler. 2016).  This study analyzed the CO2 levels of a portion of people working in a conventional office building and conversely, the levels of a portion of workers situated in a ‘Green’ building. After the study was completed, researchers found that workers who were placed in a ‘Green’ office environment had significantly higher cognitive scores than those who were working in a contemporary office building (Allen et al. 2016).

Supplying a building with an increased quantity of outside air will decrease the overall amount of carbon dioxide exposure to those inside. Additionally, the increased exposure of outdoor air will decrease the intake of other indoor contaminants. Green roofs lessen the overall energy usage of a building and in turn can be beneficial when diminishing carbon dioxide pollutants that are emitted by factories and power plants (GSA, 2011.). The implementation of green roofs directly correlates to the mitigation of a building’s carbon footprint, allowing for a more suitable working environment. To function to their full extent, green roofs rely on the vegetation planted above and their surrounding environment to absorb carbon dioxide out of the air. This vegetation, along with its natural surrounding environment, produces oxygen and removes excess CO2 from the air in addition to absorbing any other pollutant that passes through them, creating cleaner air to breathe (Page, 2017).

In order to mitigate the variety of public health issues related to urban air quality, we propose that commercial entities in urban areas be encouraged to transition to green roofing through tax incentive programs.

Green roofs offer an effective solution to urban air pollution (Oberndorfer, Lundholm, Bass, Coffman, Doshi, Dunnett, … Rowe, 2007). A green roof is defined as a roofing structure that consists of a waterproofing membrane, growing medium and vegetation overlying a traditional roof (GSA, 2011). Urban greenery attenuates roadside pollution (Islam, Rahman, Bahar, Habib, Ando & Hattori, 2012) this style of construction is an essential component of the movement  toward cleaner air (GSA, 2011).

Residential construction of green roofs offer benefits on a small scale, and in turn, may not be considered significant enough to promote future implementation. Conversely, the benefits of constructing green roofs in urban, commercial areas are unambiguous (Oberndorfer et al. 2007). [put some studies here that support the following sentence] So one can conclude that green roofs have a greater effect when constructed on a commercial, not residential, scale in urban areas.

Tax incentive programs are effective ways of encouraging “good” behavior, as it were, and we can look to the effectiveness of the U.S.’s renewable energy tax credit program as a model to demonstrate just how useful these are (Steinberger, 2017). A residential tax incentive payable up to $500, The Residential Energy Efficiency Tax Credit, has already been implemented in the U.S. Since its inception in 2005, the legislation has coincided with a great increase in the renewable sources it encouraged (Steinberger, 2017). Though the legislation was not renewed under the new administration, the credit was payable to the owner of a home that improved the energy of efficiency of their home (IRS Title 26 §25). It would not be a stretch to extrapolate legislation like this to cover commercial buildings and their owners, perhaps raising the scope of the credit to ask companies to build larger green roofs in return for larger tax credits.

Although green roofs can offer urban areas environmental benefits skeptics still debate whether or not they are financially advantageous (Page, 2017). With an estimated residential green roof construction varying from 15$ to 20$ per square foot, many critics argue that the one time installation fee may outweigh the future returns (Scholz-Barth, para. 1. 2001). Additionally, researchers found that many domestic residencies don’t posses the capability to support a green roof (GSA, 2011). Old structures or buildings with existing contemporary roofs may find that the conversion price of switching to a green roof is relatively high compared to replacing it with traditional roofing (Page, 2017). As research and construction strategies advance, it is crucial that the price of green roof installation remain affordable and feasible (GSA, 2011).

    Air pollution is a very real and very serious hazard to humans all over the world, especially in urban areas. This issue demands immediate attention and must be mitigated for the sake of global human health. The installation of green roofs is a logical and feasible solution to this problem. Through tax credits to commercial properties, green roofs’ elevated presence in urban areas can ameliorate these issues and make life a little better for everybody.

   

 

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