Menli McCreight : Environmental Science
Alec Boucher : Building Construction Technology
Adam Banks : Sustainable Horticulture
The amount of energy used for maintaining buildings is immense. In the United States alone, buildings are responsible for three-fourths of electricity consumption, over one-third of total energy use, and one-third of carbon dioxide emissions (Durmus-Pedni & Ashuri, 2010). Overall, 40% of energy and materials goes into buildings worldwide (Freed, 2006, “What do you mean by…” section). According to BuildingGreen, a website on sustainable design and architecture, in 2011 about one-fifth of energy was consumed by residential buildings, one-fifth by commercial buildings, one-third transportation, and one-third industrial (BuildingGreen, 2013). Buildings use such a large fraction of energy due to lighting, heating, cooling, power, poor insulation, etc. Researchers found that “Ninety-five percent of all the energy that enters the American economy is wasted…”(Straube, 2009, “Some people understand…”).
Conventional buildings compared to green buildings are not as efficient in reducing the amount of energy required for a product of service as technology allows them to be today. According to the United States Environmental Protection Agency a “Green Building” is a building or structure that uses environmentally responsible practices from conception until deconstruction of the building. Contemporary green buildings are superior in both carbon savings and cost savings. Green buildings use a mean 21% lower energy than conventional buildings, and with improvements and modifications conventional buildings could rival that statistic (Lin et al., 2016, p. 11). Compared to conventional buildings, green buildings save money and reduce carbon footprint by utilizing energy efficiency; converting existing buildings to green buildings can be accomplished at a low price and solve these problems.
Energy use in buildings can be drastically reduced in half through energy usage efficiency improvements within conventional buildings. While the green buildings movement originated in the 1970’s the amount of existing conventional buildings still out number the amount of newer green buildings (Edwards & Naboni, 2013). Conventional buildings are not as energy efficient due to older technology and construction techniques, lowering potential energy savings. In modern green buildings, the potential energy saving steps are implemented from the start increasing carbon savings and in cost savings (Edwards & Naboni, 2013).
There is a substantially higher startup cost in green building compared to a conventional building (Francesco et al., 2013). These extras costs are due to building material along with specialty systems that follow green design, such as photovoltaic systems and passive solar heating systems. Many times retrofitting conventional buildings is preferable than construction of a new green building because green improvements are implemented over a period of time (Durmus-Pedini & Ashuri, 2010). This spreads the cost of renovations making energy reduction a more feasible undertaking for building owners (Ariffin & Ismail, 2014).
Converting conventional buildings to green buildings doesn’t just help with energy and cost savings. The majority of people spend 90% of their time indoors and overall the quality of the indoor environments are a lot more polluted than they could be, and far more polluted than the outdoors. Building materials and poor lighting, along with other factors, are responsible for this (Freed, 2006, “Why should I care…” section). Retrofitting conventional buildings into green buildings would increase the Indoor Air Quality (IAQ), making where we spend 90% of our time more pleasant and healthy.
On a larger scale, making buildings more energy efficient will help fight against global warming by decreasing carbon dioxide levels and slowing down the rate at which we deplete natural resource levels. The International Panel on Climate change reports that targeting buildings will save the most amounts of CO2 emissions (Straub, 2009, “Buildings should already be better…” section).
Recently a social and ecological need to reduce energy consumption help promote green building practices. Freed (2006) explains the reason why there are a small percent of green buildings when the majority of designers feel the responsibility to offer greener solutions to clients and contractors. Freed (2006) attributes this gap to lack of information within the science (“This all seems to make…” section). Increasing the information within the sciences help bridge the gap between older ways of design with newer green technology and systems.
Climate change and contemporary understanding of limited resources are the driving factors for this new movement. An article by Naomi Oreskes published in Science states, “In its most recent assessment, IPCC states unequivocally that the consensus of scientific opinion is that Earth’s climate is being affected by human activities…” (Oreskes, 2004, p. 1686). Conventional buildings were built using non-energy saving techniques; however, that does not mean they are unable to have energy saving improvements made to them. These improvements will reduce their energy consumption, thus lowering limited resource use and their overall carbon footprint for the rest of the building’s lifetime.
There are two ways to cut CO2 emissions, first is by reducing energy consumed and the second is by utilizing more efficient energy. According to Straube, “it only makes sense to use renewables when energy consumption in a building dramatically drops” (Straube, 2009, “Tighter buildings…” section). As Freed (2006) explains that having energy efficient lights in a hallway when nobody’s there has an efficiency of 0%, which is why it’s important to have appliances turned off. The most efficient thing is one that turns off (Freed, 2006, “Not all green buildings…” section).
Once energy reduction is established, focus can be shifted towards energy efficiency. Green buildings both increase a building’s energy efficiency by using energy star appliances and improve the design of the building. Green buildings are designed to use energy the most efficient way possible, where that is increased insulation, increased sunlight or, room designs so that light can spread better. Scholars conducted studies between green buildings and conventional buildings to see the amount of energy used between the buildings, and they show that, “For overall buildings, the median (of energy consumption) of green is 21% lower than the figure of common buildings.” (Lin et al., 2016, p. 11). To put this in perspective the amount of energy used by a green building would be equal to amount of energy used by conventional buildings that is less than ⅘ the size of the green building.
Lighting can be greatly increased with a change in product. Straube (2009) explains that incandescent light bulbs are less than 2% efficient at converting electricity into light. Replacing incandescent lights with compact fluorescents would increase energy efficiency by at least 5%, possibly even up to 20% (Straube, 2009, “Some people understand…” section). The author found that energy efficiency can be greatly improved from a change in light bulb, and another study put it in a simpler more understanding perspective, “Replacing your burnt out light bulbs with compact fluorescents bulbs would prevent enough pollution to equal moving one million cars from the road. Natural light replaces the need for lights in the first place.” (Freed, 2006, “Why do green buildings cost more…” section). This analysis gives a much better idea of how much just changing the type of light bulb can reduce the amount of energy that is used in a building. Freed (2006) notes that we could shut down 10 ageing power plants if all the homes in the U.S. used an energy Star refrigerator (“Why do green buildings cost more…” section).
There are two main ways retrofitting conventional buildings are cost effective and can save the building owner money. First is the savings passed on through avoiding the initial start up costs of building a new building and second is the accumulated cost savings over time after retrofitting conventional buildings. While retrofitting comes at a price, these expenses are made back though cost savings in as little as three years after retrofitting according to E. Bertone et al. (2016). There are many additional financial benefits for retrofitting conventional buildings, such as Federal grants, tax incentives, and lower absenteeism (Durmus-Pedini & Ashuri, 2010). High efficient green buildings may have up to $6.68 per square foot operating cost savings compared to conventional buildings (Durmus-Pedini & Ashuri, 2010, p. 5). With time retrofitting investment costs will be made back and create a more sustainable environment.
Along with wanting to save money on energy, building owners want their buildings to be thermally comfortable. There are many ways thermal comfort is increased in green buildings, both by design and with appliances used. In green buildings the architect design the buildings to cost a little more but make up for it in energy savings. An increase of wall thickness by two inches would increase insulation value by 57% (Karatas & El-Rayes, 2015, “Each of the generated…” section). It may cost slightly more to buy the thicker lumber and add more insulation but the insulation keeps heat from transferring out of the building envelope and staying in the building to provide more warmth and making appliances run less.
To prove that green buildings are more thermally comfortable than conventional buildings, researchers ran tests and surveys in each type of building. Occupants of green buildings are more satisfied with thermal comfort than in conventional buildings (Abbaszadeh, Zagreus, Lehrer & Huizenga, 2006; Hong, Gilbertson, Oreszczyn, Green & Ridley, 2008). Both articles found that comfort in conventional buildings over fifteen years old are half as comfortable as green buildings that are less than fifteen years old, according to (Abbaszadeh et al., 2006, “Among these buildings…” section) and Hong et al. (2008, Fig. 2a).
Green buildings are healthier to occupy than conventional buildings. According to one source, conventional buildings have poor indoor air quality: “Asthma, once rated seventh, is now the leading chronic illness in children. One of the primary causes of asthma is indoor air quality” (Freed, 2006, “What is indoor air quality?” section). Singh, Syal, Grady and Korkmaz (2010) connect how asthma is related to the environment of buildings and IAQ. Increasing IAQ will decrease the number of occupants experiencing asthma.
According to Abbaszadeh, S., Zagreus. L., Lehrer. D., & Huizenga. C. (2006) green buildings have better IAQ than conventional buildings. The authors illustrate that the mean satisfaction of IAQ in all conventional buildings is low, while in conventional buildings less than fifteen years old it is two times higher. In Leadership in Energy & Environmental Design (LEED) rated green buildings mean satisfaction is four times higher than all conventional buildings (p. 365). Singh, Syal, Grady and Korkmaz (2010) argue that creating ideal levels of IAQ a company can gain 1.75 work hours annually from each employee with asthma and respiratory conditions (Figure 1).
Singh, Syal, Grady and Korkmaz (2010) also connect conventional buildings with depression; however, depression rates can decrease by retrofitting conventional buildings to green buildings. Singh, Syal, Grady and Korkmaz (2010) relate depression and stress to lighting, and lighting to daylight views. By increasing lighting, which decreases depression, a company can gain 2.02 work hours annually from each person who is diagnosed with depression (Singh, 2010, Table 1).
Along with green buildings being healthier to occupy, they prove a more productive work environment. In one study, occupants moved from a conventional building to a green building and increased mean productivity by 150% (Signh et al., 2010, “Results…” section). Furthermore, the employees self-rated their own productivity and found that in conventional buildings the average score was negative eight; in green buildings it drastically increased by ten points (Signh et al., 2010, “Results…” section).
More natural light is harnessed in green buildings increasing productivity and limiting the need for additional lighting (Signh et al., 2010, “Results…” section). Freed (2006) did a study on students based upon how much daylight was allowed into the classrooms. The results showed that “Student test scores are 15% higher in spaces lit with natural daylight” (Freed, 2006, “Why do green buildings cost more…” section). Additionally, studies in Taiwan conducted tests on the amount of light in green and conventional buildings. Han-Hsi, Chen-Peng, Ruey-Lung, Wen-Mei, Shih–Chi, and Huey-Yan (2014) note that all the sampling spots in green buildings for illuminance exceeds the recommended 500 lux by the Commission Internationale de l´Eclairage (CIE), while conventional buildings less than half of the sampling spots did not meet this recommendation (p. 236). Conventional buildings are inferior to green buildings in the amount of light increasing occupant productivity.
Along with productivity and health, studies also showed that green buildings have a direct effect on employee absenteeism. “Office workers report greatly reduced absenteeism in an environment with natural, non-toxic materials” (Freed, 2016, “Why do green buildings cost more…” section). In another study Signh A. et al. (2010) “found substantial reductions in self-reported absenteeism and affected work hours as a result of perceived improvements in health and well-being” (Signh, A. et al., 2010, p. 1666). Studies reported people had less hours out of the office and more productive work hours due to a better environment.
Some perceive drawbacks to implementing retrofitting techniques on conventional builds as opposed to building a new green building from scratch. There is some lack of flexibility with the existing conventional building structure. Buildings like these may be in question of retrofitting due to a limited energy saving potential, which can be calculated through green potential rating.
Green potential rating of existing conventional buildings are challenging because the scale that measures the potential in new green buildings is not applicable to conventional buildings, leading to inaccurate retrofitting potential data (Yahya, Ariffin & Ismail, 2014, p. 68). This inaccuracy may lead to excess cost of renovation and potentially making the retrofitting process not worthwhile for the building owner because of misleading data. These instances may be addressed with the construction of a new green building rather than trying to retrofit a conventional building.
Our goal is to promote the energy efficiency, cost reduction, productivity, thermal comfort and health benefits of green buildings in the forms of retrofitting existing conventional buildings. While retrofitting conventional buildings is not the same as building new LEED certified green buildings there are still many ways to make improvements and become energy efficient. In order to incentivize retrofitting conventional buildings a tax break will be given on the cost of retrofit. Furthermore, a tax break on the amount of energy saved from efficiency for the next three years.
Now more than ever the need for efficient buildings are felt worldwide; carbon emissions, higher energy costs and human health are at stake. “Green building is not a matter of choice or luxury but a necessity for the environmentally conscious industry professionals, owners, developers, government officials and the rest of the stakeholders” (Durmus-Pedini & Ashuri, 2010, p. 1). Buildings in the United States are responsible for three-fourths of all energy used (Durmus-Pedini & Ashuri, 2010). Retrofitted buildings with green improvements are superior than conventional buildings because they save energy, save money, are healthier and more productive.
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