Introduction
Over the years, building designs have been changing in an effort to address diverse social, economic, and environmental needs. For instance, the 20th century was characterized by the advent of the skyscraper, in which the steel framing technology was exploited in a bid to surmount the shortage of real estate in different cities in the United States (U.S. Department of energy 2008).
All of a sudden, the booming real estate market gave rise to other problems such as congestion and pollution that we now have to contend with.
As a result, the modern day building industry seems to have ushered in a new era of change whereby the main goal is to ensure that we reduce as much as possible the various forms of footprint including carbon, energy, as well as environmental footprint of both residential and commercial buildings (U.S Department of energy 2008).
At the same time, there is a dire need to conserve and optimize scarce resources such as energy, water, land, and clean air.
In an attempt to surmount these challenges, players in the building industry are now banking on transformative technologies. For this reason, developers, designers and owners are on the lookout for new ways to reduce the environmental consequences and operating costs of buildings and at the same time, ensure that such buildings appeal to the occupants. This is what has given rise to the concept of sustainable buildings.
A sustainable building refers to a structure that has been constructed in a resource-efficient and environmentally responsible manner. Such practices should be implemented in the entire lifecycle of the building beginning with siting, designing, and the actual construction.
The same practices should also be utilized when maintaining, renovating, or demolishing such a building (EPA, n.d.). For proper coordination of all these activities, there is need for the various professionals involved to cooperate at the various stages of the project. These professionals include the design team, engineers, architects, and the client (EPA, n. d.).
The practice of sustainable/green building is an expansion of and a complement to the conventional design of buildings that appears to emphasize more on utility, economy, comfort, and durability (Mumovic & Santamouris, 2009).
Even with the constant development in new technologies aimed at complementing the existing practices, sustainable buildings are designed in such a manner as to reduce the possible overall impact that such buildings could have on the built environment, the natural environment, as well as on human health. This can be achieved by ensuring that such resources as water and energy have been utilized efficiently.
Another way of achieving sustainability is by improving employee productivity and ensuring that the health of the occupant of such buildings is protected. Also, there is need to reduce pollution, waste, and environmental degradation (Mumovic & Santamouris, 2009).
Sustainability involves the ability to fulfill the needs of the current generation while still ensuring that the needs of future generations have not been compromised (U.S. Environmental Protection Agency, 2010).
A report released by the U.S. General Services Administration in 2009 reveals that it would cost less to design, construct, operate, and maintain a sustainable building compared to a conventional building. Moreover, such buildings are also characterized by excellent energy performance.
Moreover, occupants of such buildings expressed a lot of satisfaction in terms of the overall construction of the building, in comparison with their counterparts who occupied the conventional commercial buildings.
Why we need to promote the concept of sustainable buildings
Statistics show that today, the amount of energy consumed by the over 4.7 million commercial buildings and more than 114 million households in the United States is more than that which is consumed by the industry sectors.
In this case, the combined energy consumption by commercial and residential buildings in the United States is estimated at approximately 40 percent of the entire energy consumption in the country (U.S. Department of energy 2008).
As such, the social, environmental, and financial benefits associated with the integration of renewable energy technologies, energy-efficient products and designs into both residential and commercial buildings are very evident.
Nevertheless, up till now, in spite of increased consumer awareness on the benefits and significance of minimizing overall energy emission and consumption, Ellington 2004), there appears to be a very low uptake of the sustainable building concept.
In the past few centuries, people who were interested in utilizing the earth’s resources to the fullest to support its progress and development were rarely questioned but in the 21st century, we continue to witness a significant and remarkable shift towards a more accountable approach.
For instance, it is slowly dawning on developers, land owners, governments, the private sector, engineers and the general public that the earth’s resources are dwindling fast and for this reason, it is becoming increasingly important that all the parties involved make a concerted effort to ensuring that they preserve the environment so that future generations may also get a share of what mother nature has to offer.
In addition, these parties are now fully aware of the importance of striking a balance between the environment, and their social and economic wellbeing for increased sustainability (Barr, 2004). That is why we are slowly witnessing a mushrooming of sustainable residential and commercial buildings that have been constructed in an eco-friendly manner.
Even so, there is still need to create more awareness on the potential benefits of sustainable buildings if at all we are to witness profound improvements in the management of scarce natural resources and the associated negative effects once these resources are depleted.
As such, by embracing social, economically and environmentally-sustainable housing alternatives, we stand a chance to witness the challenging and beneficial large-scale change in sustainable buildings that we so much desire.
Reducing environmental impact through sustainable buildings
The aim of sustainable building is to ensure that the environmental effects of buildings are reduced significantly. Buildings usually occupy a lot of space. Reports by the National Resources Inventory show that in the United States, over 107 million acres of land is already under development.
A publication released by the International Energy Agency estimates that over 40 percent of the gross primary energy consumption in the world can be attributed to the existing buildings (U.S Department of energy, 2008). At the same time, the same report estimated that approximately 24 percent of the carbon dioxide emitted globally can be attributed to existing buildings.
Objectives of sustainable buildings
The main motives of sustainable buildings include economic, social, and environmental concerns. On the other hand, the current sustainability initiative requires the synergistic and integrated design of new buildings, along with a retrofitting of the already existing buildings (U.S. Environmental Protection Agency, 2010).
The strategy, commonly referred to as sustainable design, is aimed at creating synergy between newer sustainable building and the existing conventional buildings.
Sustainable buildings encompass various techniques and practices aimed at not only reducing, but also eliminating the effects of buildings on both human health and the environment.
The practice of sustainable building usually stress on the importance of exploiting renewable resources, such as photovoltaic techniques, trees and plants through rain gardens and green roofs, as well as ensuring that we reduce rainwater runoff (California Sustainability Alliance, 2011).
We have quite a number of approaches that can be useful, such as replacing asphalt or conventional concrete with permeable concrete or packed gravel. Such an approach is intended to enhance the replenishment of groundwater.
The technologies and practices used in sustainable building are constantly changing and they also tend to vary from one region to another. However, the fundamental principles do not change from one region to another.
Some of the basic principles of sustainable building include optimizing water efficiency, siting efficiency, materials efficiency, structure design efficiency, quality enhancement of indoor environment, water and toxic reduction, and maintenance and operations optimization (California Sustainability Alliance, 2011).
Essentially, sustainable buildings are geared towards the optimization of one or more of the aforementioned basic principles. Through the use of the most suitable synergistic design, we can be able to achieve an improved gross effect of the various technologies adopted in sustainable building.
Sustainable building design
Developing sustainability in buildings means that we need to embrace techniques that encourage biodiversity, protect and conserve water quantity and quality, protect the air, minimize soil loss, encourage recycling and reduce waste, minimize use of fossil fuel energy, minimize noise, and encourage the selection of suitable building materials.
Sustainable building design takes into account each one of these components with a view to reducing the overall effects of such a building on the environment (Allen & Iano, 2008).
From an aesthetic point of view, sustainable design enables us to design a certain building in a way that ensures harmony not only with the natural environment, but also with the natural resources as well. In spite of the constant changes in the definition of sustainable building design, there are six basic principles that do not change:
Site optimization
Proper site selection is the first step towards the creation of sustainable buildings. Site selection also takes into account the rehabilitation or reuse of existing buildings. It is important to ensure that potential sites are screen first prior to purchasing (Allen & Iano, 2008).The selection process should also be optimized for the different criteria.
The whole interdisciplinary team should be involved in the process of selecting a site. There is a need also to assess a number of sites to check if they are consistent with the goals and priorities of the entire team. The collection of data and its assessment should facilitate such an exercise.
It is also important to address a number of questions such as whether the site is a natural landscape, or the site enjoys a sufficient access to reliable and efficient public transport. It would also be important to determine if it is possible to develop the land effectively and still control for excess erosion and sediment.
The existing native vegetation should also not act as a hindrance to the construction if left. The nature of energy for use in a building is dependent on a number of factors such as the landscape and orientation of the land on which the building has been constructed.
The location of the building will also affect the mode of transport to adopt. Another crucial element in optimizing site design is the issue of siting for physical security (Allen & Iano, 2008). Other issues that we need to consider include the perimeter lighting and parking.
In addition, vehicle barriers should also be considered. It is always important to ensure that the site of a proposed building design gels with the requirements for a sustainable building. This should be the case whether the design is meant for a new building or even in the case of a retrofit.
Consequently, it becomes easier to ensure the success of a building project. Another important factor that we need to also take into account when considering the site of a building is stormwater runoff. In this case, the building should be constructed in such a way that we can easily contain or reduce this menace.
Energy use optimization
The supply of fossil fuel is dwindling fast not just in the United States, but across the globe as well. As such, there has been a rapid increase in concerns for energy security and independence, as well as the possible effects of global climate change that often accompanies the use and depletion of fossil fuels.
For this reason, it has become increasingly important to find new ways that will increase efficiency, reduce load, and make use of renewable sources of energy (Ellington, 2004). Increasing the energy performance a given building is critical because it also ensures that such a building becomes energy dependent.
Both the private sector and the government are working hard to see to it that more building attain net zero energy levels in the decades ahead. This is largely seen as the starting point of a journey towards energy sustainability.
Although sustainable building design may appear expensive in the short-term nevertheless, they have been shown be energy-efficient in the long-run. For instance, majority of the office buildings today are constructed using cheaper black roofing. These roofs are able to absorb extra heat and when the usage of central air conditioning systems is increased, this helps to offset the extra heat absorbed.
One study revealed that a certain company managed to save up to $ 16 million dollars annually when it decided to adopt a reflective roofing system (Chang 2000). The money saved would have gone to offset the air-conditioning bill. Adopting such a practice would mainly benefit such cities as New York and Atlanta that have been affected the most by the heat-island effect.
This is a low system phenomenon that results in concentrated rainstorms and higher temperatures over a specific area. The phenomenon is mainly common in cities characterized by a shortage of black roofing, trees, and a substantial number of pavements (Chang 2000).
Conserving and protecting water
Fresh water is fast becoming a scarce resource in many sections of the country and for this reason, there is need to ensure that a sustainable building use water very efficiently ((Allen & Iano, 2008). In addition, such a building should also be designed in such a way that it can recycle and reuse water for on-site applications, depending on how feasible such a practice is.
Environmentally friendly materials
One of the basic rules in sustainable building is that the construction material of choice should minimize global warming. In addition, it should not have an effect on human toxicity, and should also reduce the environmental effects of the building’s life-cycle.
Such materials have also been noted to have reduced effects on both the environment and human health (Yan & Stellios, 2006). Besides, constructing buildings using environmentally friendly materials can lead to less disposal costs. It also results in improved worker safety and health.
Improved indoor environmental quality
Improving the quality of the indoor environment of a building is critical since poor quality of air can affect the health, productivity and comfort of the occupants. One of the key elements of a sustainable building is the ability to enhance daylighting (Yan & Stellios, 2006). This can be achieved by having in place suitable moisture and ventilation controls.
Improving maintenance and operational processes
Besides improving the design of a building, along with the construction components, there is also the need to maintain the build in a manner that will ensure that it remains sustainable.
It is important to take into account the maintenance and operational issues of a building at the preliminary design stage as this will go a long way into improving productivity, enhancing the working environment, preventing system failures, and reducing resource and energy costs (U.S. Environmental Protection Agency, 2009).
It is also important to ensure that the personnel involved in the daily operations of a building take part in the initial design as well as the developmental stages so that the building is maintained in the most efficient manner.
The role of a designer is critical because they are in a position to specify the systems and materials that when used in the construction of the building will result in reduced and simplified maintenance requirements. At the same time, it becomes easier to identify building materials that do not need a lot of energy and water to maintain.
Improving indoor environment quality
Improving the air quality of the indoor environment is a vital step in helping to enhance the image of a sustainable building. As such, it becomes important to reduce volatile organic compounds in a building for enhanced circulation of air.
For example, well designed ventilation systems allow for the entry of sufficient and cleaner air into the building (U.S. Environmental Protection Agency, 2009). Reduce emissions from a building also enhances the interior air quality. This can be realised by making sure that the materials used to manufacture the interior products has very low or no emissions that would compromise the quality of air.
Most maintenance/cleaning products and building materials emit gases, and some of this gas can be toxic to the occupants and to the building as well. This is because such gases have a deleterious effect on the comfort, health and productivity of the occupants (U.S. Environmental Protection Agency, 2009).
By avoiding the use of such products, the interior environmental quality of a building can be enhanced. When we have water condensing on the interior surfaces of a building, this can result in microbial growth. To overcome such a problem, it is important to ensure that the building’s envelope is tightly-sealed and well-insulated.
Energy efficiency
Sustainable buildings should ideally be efficient in terms of energy consumption. Such efficiency often involves the activities of extracting, manufacturing, and installing the building materials. Energy consumption should also be geared towards the provision of such services as power for equipment and heating.
The efficiency of the building envelope can be improved by ensuring that only insulated floors and ceilings have been used, and that the windows are of high efficiency. Passive solar building design is yet another strategy that can also be used (U.S. Environmental Protection Agency, 2009). Most low-energy homes utilize this strategy.
The strategic placing of walls and windows through orientation enables the occupants to maximize on the use of light coming into the building through the roof and the windows. At the same time, the strategy enables designers to utilize solar energy to the maximum during winter. In any case, one can greatly minimize electric energy demand by adopting daylighting technique.
The provision of extra natural light would also be useful. When you factor in solar water heating, the energy costs of a sustainable building are reduced further (U.S. Environmental Protection Agency, 2010).
Examples of renewable sources of energy that can be adopted in a sustainable building include solar power and wind power. The use of renewable sources of energy would therefore result in a major reduction in potential environmental impact on such buildings.
In a bid to conserve energy, sustainable buildings should be constructed such that it is easily to identify and implement the various energy saving measures. Energy retrofits are by far more expensive compared to conservation and as such, a lot of effort should be dedicated to ensuring that we conserve energy.
One of the strategies of ensuring that we have reduced our energy usage is by targeting those items that consume a lot of energy in the building (Allen & Iano, 2008).
For example, in a hotel, space conditioning (that is, cooling and heating) has been noted to utilize the most amount of energy. Therefore, in trying to conserve the energy consumption pattern of a hotel, a lot of efforts should be made to ensure that there is no heat transfer that takes place within the building.
Other effective strategies that can also be adopted include decreasing infiltration, improving windows, insulating ductwork and exterior partitions, as well as retrofitting lighting fixtures. Another strategy that if implemented can lower costs is to ensure that during off peak times, electricity usage has been shifted (Allen & Iano, 2008).
The users of a sustainable building should form the habit of always saving energy. There is not much investment that goes into conservation measures and as such, they should be utilized more often. In terms of reducing operating costs, conservation measures have also proved to be the most cost-effective.
Materials efficiency
Certain building materials are considered as being sustainable. They include such renewable materials as straw, and bamboo, recycled metal, dimension stone, lumber obtained from certified forests, and recycled metals.
Other non-toxic, renewable, recyclable, and/or reusable materials that can also qualify as sustainable building materials include sheep wool, linoleum, truss, compressed earth block, baked earth, sand stone, flax linen, cork, wood fiber plates, and expanded clay grains, among others (EPA, n. d.).
Other materials on the suggestion list of the Environmental Protection Agency (EPA) for inclusion as sustainable building materials include foundry sand, coal combustion products, and demolition debris (EPA, n. d.). It is also recommended that building materials be extracted and produced closer to the site of the building as a way of reducing energy that would be expended upon their transit.
Whenever possible, it is also recommended that the manufacturing of building material should take place off-site, after which they should then be delivered on-site. This is aimed at increasing benefits of off-site production, including reduction of recycling, reduced waste, less dust and noise, and high quality elements.
Waste reduction
Sustainable building is committed to ensuring that there is a drastic reduction in the wastage of building materials, energy, and water, among other vital resources. In addition, it is also important to ensure that water is not wasted when undertaking construction.
Engineers involved in the construction stage of a sustainable building should ensure that they minimize the volume of materials that end up in landfills (Allen & Iano, 2008). This way, it becomes easier to reduce the amount of materials in the landfill.
Once the useful life of a building is over, most of them are demolished and the ensuing waste finds its way into landfills. Though deconstruction, such waste could be harvested and reclaimed to form useful building material (EPA, n. d.). We can also reduce wastes by extending the useful life of a building.
Water Efficiency
The concept of sustainable building is also concerned with activities aimed at ensuring that the protection of the quality of water is assured, and that the consumption of water has been minimized. One of the fundamental aspects of water consumption is that in certain areas, the supplying aquifer may not be able to sustain demand for water because its ability to self-replenish is slower (Mumovic & Santamouris, 2009).
For this reason, the personnel involved in the maintenance of such buildings should ensure that the water collected on-site has been put to good use by re-using it whenever possible. Protecting and conserving water in a building can be ensured by installing a dual plumbing design. This way, the occupants of a sustainable building can be assured throughout its entire lifetime.
As a result, it becomes easier to recycle the water used to flush toilets, thereby ensuring water conservation. The use of water conserving fixtures like low-flow shower heads and ultra-low flush toilets can also help to reduce waste-water (Mumovic & Santamouris, 2009).
Also, the non-sewage water could also be put to better use, like for irrigation purposes instead of just letting it go to waste. This way, we can be able to reduce the demand for water from the local aquifer.
Water conservation
In order to minimize the overall water usage, efforts should be made to prevent pipes from leaking as this amount to wastage. How water pipes can also be insulated, and water meters installed. Water meters enable the collection of data on the consumption patterns of water.
This way, one can easily establish specific water reductions goals with the intention of estimating the success of water conservation. Collecting rain water can also help to supplement piped water. In case the plumbing system within the building is leaking, it may result in over 10 dumping of water.
In order to reduce such leaks, a concerted effort should be made to ensure that there is proper and regular maintenance of the plumbing system (Yan & Stellios, 2006). Use should b made of low flow fixtures for they have that they are easy to install, not to mention that they are also cost comparable. The production of hot water should take place closer to the points of usage.
This avoids wasting a lot of water and energy used to heat this water. One can save a lot of energy and water by increasing installing recirculating and pipe insulation units.
Conclusion
Sustainable buildings have gained a lot of popularity in recent years as it is starting to slowly dawn on us that our natural resources are dwindling very fast. For this reason, we need to ensure that we conserve energy, materials, and other resources such as water by adopting efficient and effective building principles.
The main motivating factor for sustainable buildings is to ensure that the economic, social, and environmental concerns of a building are addressed. As such, sustainability buildings aim to ensure that the environmental impact of buildings is reduced as much as possible.
Sustainable buildings often refer to those structures that have been designed in a resource-efficient and environmentally responsible manner. Such practices should be implemented in the entire lifecycle of the building starting with the basic step of site selection whereby the site selected for constructing the building should be environmentally friendly.
Some of the common techniques applied in the design of sustainable buildings include proper site selection, optimizing the use of energy, use of environmentally friendly materials, improved indoor environmental quality, optimizing maintenance and operational activities, and improving the quality of the indoor environment.
The entire building design should also emphasize on achieving an economic, social, and environmental balance. The same goes for the actual operation and construction.
In addition, the maintenance, renovation or demolition of such a building should also follow these practices. The various professionals involved in the construction of a building need to cooperate so that all these activities can be properly coordinated.
Reference List
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