Today, more than ever before, sustainability concerns are assuming a central role in any development process in most countries, in part, due to the increased challenges brought forward by a myriad of externalities such as global warming, acid rain and deforestation, among others. As a direct consequence of the germane issues demonstrated by sustainability concerns, governments around the world continue to orchestrate programmes and policy frameworks aimed at improving sustainability.
Estidama, discussed in the two articles, is one such integrated programme that has been carefully designed to renovate Abu Dhabi and make it the sustainability capital of the Middle East by the year 2030 (Estidama 2030 para. 1). It is the purpose of this essay to offer a critical summary of the two articles, in the process bringing into fore issues that are relevant to the Estidama Project.
The Estidama project is all about assuming an integrated and holistic approach to sustainable building design within the emirate of Abu Dhabi. In broad terms, the initiative aims to advance sustainability and improve livability in the emirate under the realm or domain of Abu Dhabi Vision 2030 (Estidama Advances para. 1).
Apart from devising guidelines that will ensure that any form of development within the emirate adheres to sustainable design, the initiative also aims to be a forerunner in ensuring the objective or unbiased growth of both residential and commercial developments incorporating sufficient greenery and landscaping (Estidama 2030 para. 2).
The Estidama initiative, according to experts in the construction and landscaping industry, is not only good for business, but will make Abu Dhabi a model emirate in terms of incorporating both local and built environment in the regional context. Of importance is the fact that the Estidama project, once complete, is anticipated to conserve energy and water use by up to 30 percent (Estidama 2030 para 6).
The landscaping industry is also set to benefit from the Estidama venture, and analysts predicts that business within the industry will double in volume to surpass Dhs60 bn by 2010 (Estidama 2030 para. 7). In consequence, experts within the landscaping industry agree that such a sustainable project is also beneficial to their own businesses since it will cushion them against extreme competition, dwindling profits and high expenses.
Many sustainability programs around the world have well-designed benchmarks for measuring performance, and Estidama is no exception. Indeed, Estidama is the first sustainability programme in the Arab World to launch a sustainability rating mechanism aimed at evaluating sustainability performance of a multiplicity of developments such as buildings, pavements, communities, city parks, highways, and villas (Estidama Advances para. 1).
The rating mechanism for Estidama development initiatives is known as Pearl Rating System (PRS), and encompass &a Pearl Building Rating System (PBRS), a Pearl Community Rating System (PCRS) and a Pearl Villa Rating System (PVRS) (Estidama Advances para. 2).
Of importance is the fact that these rating mechanisms provide a set of quantifiable strategies for rating sustainability performance of buildings, communities and villas using the four variables set out within Estidama Framework, that is, economy, environment, community and culture.
Moving on, it is also worth noting that Estidama rating mechanism addresses seven classes, namely, Integrated Development Process, Natural Systems, Livable Communities and Buildings, Water, Energy Materials and Innovating Practice (Estidama Advances para. 3).Credits as well as weights are awarded to each class depending on performance, with 1 credit point representing the lowest while 5 credit points represent the highest.
In measuring the sustainability performance of various types of developments, it serves the purpose of this paper to mention that the PBRS is applied to general buildings, retail outlets, institutions of learning, offices and multi-residential facilities, while PCRS is applied to facilities sustaining up to 1000 permanent residents (Estidama Advances para. 4).
Stakeholders are quick to point out that sustainability is the cornerstone of any new development and that the Estidama project will offer the necessary momentum to achieve Abu Dhabi vision 2030, hence transforming the emirate into a model of an international sustainable capital. It is also felt that the PRS will offer a dependable and consistent sustainability benchmark tool to be used in the region in line with Estidamas cross-disciplinary strategy (Estidama Advances para. 6).
The PRS cover three stages, namely, the Pearl Design Rating (PDR), Pearl Construction Rating (PCR), and Pearl Operational Rating (POR). As the name suggests, the PDR within the Estidama framework is only engaged at the design phase of any development, not mentioning that it is applied until construction is complete.
The PCR, on its part, is applicable for two years after construction is complete whereas the POR is applied to evaluate the operational performance of an already complete project. In most occasions, POR is applied for a minimum of two years after a particular project has been completed and when such a project reaches a minimum tenancy of 80 percent (Estidama Advances para. 7).
All in all, it can be concluded that these rating mechanisms have not only assisted the Estidama initiative to ensure that sustainability targets are being dealt with through all stages of designing and developing projects, but they also offer a framework for meeting sustainable objectives by underlining water and energy efficiency, reduced use of motor vehicles, maximum selection of building materials, indoor and outdoor environment quality, resource preservation and conservation and, finally, reduction of waste (Estidama Advances para. 9-13).
Works Cited
Estidama 2030 to make Abu Dhabi the Sustainability Capital of Middle East. 2008. Web.
Estidama Advances the Arabs World First Sustainability Rating System. 2010. Web.
Many nations throughout the world are faced with the challenge of climate change. The United Arab Emirates is not an exception to this problem. Over the years, the UAE has had an increased number of buildings under construction. This has resulted to the construction of impressive buildings and building projects that have resulted to spectacular buildings such as the Palm Jumeirah and Burj Dubai.
The construction of these buildings is respectable but at the same time, it has resulted to increased consumption of energy. This generated a need to search for better ways of construction that would reduce energy consumption and depletion of the existing natural resources even though the Emirates boasts of the worlds largest possession of these resources.
Consequently, the government in the United Arab Emirates resolved for the implementation of better and advanced construction strategies that would ensure energy was conserved therefore providing a solution to the increased rate of pollution that has been on a steady rise with the increase in the number of buildings.
This led to the introduction of green buildings in the Emirates as a sure method of decreasing energy wastage and pollution while at the same time commencing with their building activities to meet global environmental changes in the business world.
Several factors in the Emirates contribute to the consumption of large amounts of energy. This includes longer summers, desert conditions, little amount of rainfall and temperatures that range up to 40 degrees or higher. This causes them to rely heavily on applications that consume large amounts of energy such as air conditioning and the desalinization of water systems. This, in addition to the sky rocketing buildings gives enough evidence of the high energy consumption in the Emirates.
Adopting a better alternative in architectural designs and methods can lead to much reduced effects on the environment. In an interview carried out Habiba Al Marashi who is the chairperson of an environmental Group in Dubai known as Emirates Environmental Group she said Sustainable architecture is one of the many ways by which we can measurably minimize the impact of our growth on the ecosystem.
I would like to urge our designers and builders to look inwards towards our architectural traditions and heritage to seek solutions to make a truly greener and progressive UAE, (Janardhan, 2010, par. 6).
Green buildings serve as a solution to the establishment of an environmentally sound system and creation of efficiency in daily activities by creating reasonable space using a better and improved integrated approach to building design and construction. As a result, an environment that is comfortable for everyday activities while at the same time reducing operational as well as maintenance costs can be achieved in the Emirates.
The green buildings are already being constructed in the Emirates and with time the strategy would be fully incorporated into the UAE. It has become essential for the UAE to assimilate this construction method in light of the current rate of energy depletion and exhaustion of natural resources as well as increased environmental pollution. Incorporation of the green building architectural designs is fundamental for a stable commercial and natural environment in the Emirates.
There are five prerequisites of green building which are already being implemented by architects as well as engineers in the Emirates. The fundamentals of green building include sustainable sites, energy efficiency, water-use efficiency, environment-friendly materials and indoor environmental quality (Janardhan, 2010, par. 10). It is an improvement that the engineers and designers of different buildings are incorporating one or more of these steps in construction of current buildings. However, a more holistic approach would be developed if all the fundamentals of green building would be incorporate in the construction of these buildings rather than using one or two of the prerequisites.
The Emirates are using the concepts of green building to employ energy-efficient strategies as well as incorporating the use of recycled materials and recyclables in the construction of buildings. This type of environmental- friendly designs ensures that full utilization of limited resources is achieved to satisfy both the needs of the architects and that of the consumers.
The green buildings encourage the conversion of solar energy into electricity for use in cooling since as mentioned earlier the temperatures in the Emirates can exceed 40 degrees. The electricity can also be used for heating. Other environmental conserving activities involve the use of high winds which can be converted into electricity using rooftop generators.
The green building project also utilizes technology in the conversion of municipal waste to biogas and useful bio-fertilizers. Water which happens to be a costly commodity in the Emirates due to the process of desalinization can also be conserved by preventing excessive consumption of water which is a strategy employed by the green buildings. If the United Arab Emirates incorporates the green building strategy, there would be lots of benefits accrued from it for the countries.
The Leadership in Energy and environmental Design (LEED) is a body which determines the number of factors that go into consideration for the determination of an appropriate green building project in different countries. Different countries have their own special specifications for a green building project due to various factors such as climate and the economic capabilities of the country.
The LEED uses a wide criterion so as to come up with different degrees of sustainability for different green buildings. For the UAE, the American LEED structure was modified to generate the LEED Emirates that has already been utilized in construction of green buildings in the UAE. One of the buildings that has been constructed using the LEED is the Pacific Controls Headquarters which is the first building that was constructed using the LEED in Middle East and about the 16th throughout the world.
Some of the technologies that were used in the building for reduction of environmental degradation are the Roof mounted photovoltaics powering daytime artificial lighting A solar thermal air-conditioning system CO2 monitoring for indoor air quality Landscaped areas irrigated using rain water and recycled waste water 50% of construction materials sourced locally 10% of building materials by cost made from recycled goods (Rashid, 2007, p. 5)
The development of the green building has led to increased awareness of the environment and the potential dangers other forms of construction have on the environmental condition of a country and of the entire world as a whole. Green building as led to reduced energy wastes and better strategies of construction that have ensured energy costs are minimized.
The UAE has employed the use of green building. As a result, there are various advantages that are going to accrue to the country due to the adaptation of the LEED Emirates strategy in construction. More building constructions that are based on LEED are yet to be constructed in the UAE and the benefits accruing to the use of this strategy would be visible after a period of time.
Reference
Janardhan, Meena. (2010, July 19). Land of Black Gold Focuses on Green Buildings. Web.
Rashid Al Maktoum. (2007, October). The Sustainable Vision of Dubai. Web.
New York is believed to be the worlds oldest city and this aspect makes it a historic place that attracts tourists and locals. The booming economy of this city is anchored on its well established infrastructure and the availability of social amenities that attract investors from across the world. Most people were attracted to this city because they believed it was cosmopolitan and thus there were high chances that all products and services were available in its business establishments.1
In addition, this place is located in the heart of America and surprisingly lacks political interests. Therefore, it was able to attract stakeholders in the business field because of its peaceful environment.
Historians believe that this is the only city in America that experienced less workers strikes even though it was the hub of its economy. Most analysts are usually puzzled by the magic effect of New Yorkers that ensured they protected their city with zeal and zest.2 This discussion explores the historical and architectural aspects of the Empire State Building.
The great depression of the 1920s that America experienced gave few investors opportunities to expand their business operations and this is where the history of this building starts.3 Most rich people suffered a significant loss after the market rice of their shares in the stock market slumped. Most people had bought shares on margins and the results of the fall of the Dow Jones Stock house meant that they lost their money.
The economy of America was devastated and it was impossible for people to make a major investment in the construction industry. In addition, America was involved in conflicts with other countries like Germany and Japan and its citizens were reluctant to invest in real property. Lastly, the Second World War was beckoning and it is very surprising that despite the destruction suffered during the First World War, nothing held back the construction of this building.4
The building was constructed on a farm that housed a hotel frequented by the elites of this city. This was a very prestigious place and only the rich and influential New Yorkers were allowed in the hotel. It was a members only recreational center and this earned it public scorn for open discrimination and creating classes in New York. Most of these rich people came from Indiana and that is why the limestone for this building came from this region.
It is surprising that William F. Lamb of the Shreve, Lamb and Harmon Construction Company produced the plan for this building within two weeks after he was contacted. A 103 story building plan ought to have taken at least two months to be completed. However, this architect managed to do this within two weeks yet the results of his work are incredible.
This earned this company world recognition and annual gifts and flowers continue to trickle in Williams office. In addition, the design of this building started from the top and ended with the foundation as opposed to the traditional down-up approach.5 Moreover, this building took less than 500 days to be completed and this makes it a tourist attraction site because it disapproves the laws of nature.
It is surprising also that most of the 3,400 workers were immigrants from Europe when the locals were in dire financial constraints due to the effects of the Great Depression. Critics do not understand why this building was constructed from immigrants from Europe yet this continent was at war with America. Most workers were unlawfully sacked and this made some of them to commit suicide by jumping from top flows.
In addition, this building has seen more than 30 people committing suicide and unconfirmed report shows that about 18 of them died while it was under construction.6 Lewis Wickes Hine provided important information about the plight of workers on this site through his photos.
Most people believe that the construction of this building was fastened because the owners and constructors wanted it to be the tallest in New York. There was competition for this title from 40 Wall Street and Chrysler Building that were also under construction during this time.
The most memorable event in the history of this building is that it was officially opened by President Herbert Hoover by a switching on its lights (with the push of a button) while seated in his office in Washington. However, this does not mean that this president was in good terms with the stakeholders of this building. President Franklin D. Roosevelts victory over Hoover was celebrated by the installation and switching on of the buildings tower lights.
Critics claim that the building was not fully occupied for a long time after completion because investors had lost a lot of money in the stock market. In addition, it was located from the major public transport terminals (Penn Station and Grand Central Terminal) and this means that it was very far from the public.
The 1945 plane crash that led to the death of 14 people forms part of the dark history of this building.7 The 2012 shootings involving the police, Jeffrey T. Johnson and his co-worker led to the death of two people and injured several others. This building held a 42 year record as the worlds tallest building between 1925 and 1967.
The modern cinema and film industry uses this buildings observation deck to promote their productions. Films like An Affair to Remember and Sleepless in Seattle are some of the productions that capture the attractive view offered by this building.
Architecture
Most people expected this building not to last for long because it was completed within a very short time than is possible for its type.8 In addition, critics and the public expected it to have an old fashioned architectural presentation that did not pay attention for the need to maintain high structural and cultural values.9 However, their perceptions were proved wrong when it was completed. The surprises started during its opening when the lights were switched on from Washington, D.C. by President Hoover.
The full height of this building is 1,453 feet and it has 83 stories most of which are commercial and office spaces. The observation decks of the 86th floor offer a scenic view of the entire city and give viewers the rare chance of feeling the magnificent value of design and fun. The presence of the Art Deco tower in 16 stories makes this building a magnificent construction. Broadcast antennas surrounded by automatic lighting systems decorate the very top of this building.
The presence of 6,500 windows allow light to penetrate to all rooms and thus makes the building to shine during daytime.10 In addition, its 73 elevators ensure people move easily from one floor to another. The building has 1,860 steps to reduce congestion in elevators and offer alternatives to those that are afraid of speed and heights. Its base is about 2 acres. The elevators are high speed and this means that users take a few seconds to get to its top floor.
This floor is unique because it has a gift shop that enables users to select their favorites from a list of the known prestigious presents.11 In addition, the architectural design and other important aspects of this building are exhibited in a room on this floor. The whole building is heated by a low-pressure steam that regulates the temperature of the rooms, corridors, elevators and steps to ensure workers are in a favorable environment.
Its electrical system has been overdesigned to create room for future adjustments. This ensures new owners can change the design of their rooms without interfering with its tensile strength and altering its plan. It has a stainless steel canopy and glass enclosed bridges at the entrance that make it magnificent and attractive to visitors. Its unique eight illuminated panels on its north corridor make it peculiar. Its top is illuminated by floodlights with different colors that match important events in Americas history.
The signal transmission mast at the top of this building makes it unique and replaced the anticipated airstrip that proved impractical and risky.12 Its observation decks are regarded as the most popular world outdoor viewpoints because its 86th floor offers a 360-degree view of New York City.
Another observation deck can be found on the buildings 102nd floor. The second floor has motion simulators that complement the aesthetic value of this building. These decks have five entrance lines that generate income for the building which is more than what it gets from renting its space.
Bibliography
Aaseng, N., Construction: Building the Impossible, Minneapolis, MN, The Oliver Press, Inc, 2013, 33-51.
Amory L., A Farewell to Fossil Fuels , The New York Times, 2012.
Barron, J., Overhead, a Lobby is Restored to Old Glory , The New York Times, 2009, 21.
Bascomb, N., Higher: A Historic Race to the Sky and the Making of a City, New York: Doubleday, 2003, 71.
Covington, O., A Look at the Historic Reynolds Building , The Business Journal, 2012, 50.
De Moraes, L., Spike TVs Last Family on Earth: Coming to a Bunker near You , Washington Post, 2012, 88.
Goldman, J., The Empire State Building Book, New York, St. Martins Press, 2009, 59.
James, T., The Empire State Building, New York, Harper and Row, 2010, 99.
Kingwell, M., Nearest Thing to Heaven: The Empire State Building and American Dreams, New Haven, Yale University Press, 2006, 89.
Lelyveld, J., The Empire State to Glow at Night , The New York Times, 2010, 21.
Tauranac, J., The Empire State Building: The Making of a Landmark, New York, Cornell University Press, 2014, 45-46.
Wells, C., Empire State Building Lights Up to Broadcast Election Results , Daily News, 2012, 39.
Footnotes
1 Charles, Wells, Empire State Building Lights Up to Broadcast Election Results , Daily News, 2012, 39.
2 Nathan, Aaseng, Construction: Building the Impossible, Minneapolis, MN, The Oliver Press, Inc, 2013, 33-51.
3 John, Tauranac, The Empire State Building: The Making of a Landmark, New York, Cornell University Press, 2014, 45-46.
4 Lovins, Amory, A Farewell to Fossil Fuels , The New York Times, 2012, 19.
5 Joseph, Lelyvel, The Empire State to Glow at Night , The New York Times, 2010, 21.
6James, Barron, Overhead, a Lobby is Restored to Old Glory , The New York Times, 2009, 21.
7 Mark, Kingwell, Nearest Thing to Heaven: The Empire State Building and American Dreams, New Haven, Yale University Press, 2006, 89.
8 Neal, Bascomb, Higher: A Historic Race to the Sky and the Making of a City, New York: Doubleday, 2003, 71.
9 Theodore, James, The Empire State Building, New York, Harper and Row, 2010, 99.
10 Owen, Covington, A Look at the Historic Reynolds Building , The Business Journal, 2012, 50.
11 Jonathan, Goldman, The Empire State Building Book, New York, St. Martins Press, 2009, 59.
12 Lisa, De Moraes, Spike TVs Last Family on Earth: Coming to a Bunker near You , Washington Post, 2012, 88.
This article looks into the critical subject of embracing green building codes and standards in the construction industry of the United States. Based on an analysis of buildings that have been approved for embracing green practices across the United States, the researcher reveals that there are significant variations in the level at which green practices are enforced by different companies in the construction industry in the United States. As such, the researchers ascertain the need to rethink and develop new standards other than the LEED system that is used to certify green buildings.
Introduction
Environmentalism is now than ever before considered to be a central issue in all attributes of development across the industry. The building industry in the United States is not spared when it comes to the question of embracing the green paradigm in building and construction. The concern here is about the extent to which building and construction experts consider the issue of green building in their construction activities. This paper presents a critique of a research article from USA Today titled, In U.S. building industry, is it too easy to be green? . (Schnaars and Morgan 1).
Research question and objectives
A research conducted by the USA Today revealed that the U.S. Green Building Council, a body that is mandated to certify buildings that are green in the United States, has certified approximately 13500 buildings that are used for commercial purposes. This is an interesting thing to note, considering that fact that any building that is certified by the U.S. Green Building Council is required to have passed the scrutiny under LEED, which is the rating system that ascertains green buildings as developed by the U.S. Green Building Council (Schnaars and Morgan 1).
The main question that is explored in the article is whether the green experts pay attention to most or all the details of green building as enumerated in the LEED system. What is observed out of the constructions that have been so far certified is that the designers do not consider all the details of green building as required by the U.S. Green Building Council, but they tailor buildings in their own way as long as they factor green attributes in the design of buildings. This is notable in the assertion that, designers chart their own course to certification, choosing from roughly 50 options that range from minimizing light pollution and storm water runoff to maximizing interior daylight and ventilation (Schnaars and Morgan 1).
Subjects and target population for the study
It is apparent that this study focuses on the commercial building and construction industry. The research further pays attention to the entire public, more so the general population who are the consumers in the sense of using the buildings, the individuals, and companies in the construction industry, and the people who advocate for green practices in the United States in particular and the world at large. While the study does not directly target the construction industry in the United States, it does reveal a number of things about the justification of green practices in the commercial building and construction industry in the United States. It is evident that most builders in the commercial building industry in the US make gains when they align with the design as embedded in LEED (Schnaars and Morgan 1).
Statistical analyses
The authors of the research highly deployed comparative analyses in ascertaining the embrace of green practices in buildings across the United States. With the graph showing the increase in the number of green buildings in the United States, it was easy to ascertain other issues about green buildings. Among these issues is the question of cost and how it is met by the investors in the building industry. Comparisons revealed that green buildings often cost more, especially for the builders who enforce most of the better green practices in construction as laid down by LEED, as well as other practices that keep emerging.
Strengths and weakness of the research
The most interesting thing in the article is that it pays attention to a specific research issue; the level at which green practices are factored in construction of commercial buildings in the United States. This is vital in citing the differences as has been done in the article.
A look at the paper denotes the deployment of a high level of comparison, which means that most of the comparisons might have been done without the deployment of real research for justification of outcomes.
Conclusion
The study reveals significant differences in the quality of buildings that are LEED certified. In other words, LEED is an ineffective way of ascertaining the buildings that embrace green practices in their design and construction. The research further reveals that the LEED system has its weaknesses, especially in implementation and should not be used to set up green building and construction standards in the building and construction industry. The researchers point at the need to come up with other practices that can enhance the intensity with which the building companies in the commercial building and construction industry embrace green practices.
The Empire State Building is a 102 storey, 1,250 feet tall building located between the Fifth Avenue and West 34th Street in New York; with an office space of 2.8 million square feet.
It was constructed in 1931and stood as the tallest building in the world until 1971 when World Trade Center was constructed although; it reclaimed the tallest building in the world in 2001 after the destruction of the World Trade Center. It was designed by William Lamb and was constructed began in1930 and completed in 1931 by Starrett Brothers and Eken Contractors.
The landmarks outside design is made from Indiana limestone, which is eight-inch thick. The floor slabs are eight-inch thick, made up of one-inch cement layer and seven-inch of ember and concrete. All columns, girders and floor beams were made of steel sheathed with 1-2 inches of brick terracotta and concrete.
There was almost no spacing between the floors and there were no air vents for air circulation penetrating fire extensions, floors and ceiling, with each floor having its own HVAC system. The elevator and utility shafts were masonry bolted together and in the fire escape there was a four inch brick enclosed. This was designed to allow occupants to escape in case of fire through the staircase without fire filling up the escape space.
On July 28, 1945, a fateful B-25 Mitchell bomber crashed on the building causing the building to burst into flames. Although it did not collapse it was seriously damaged. This is due to the strong and rigid steel frame structure on the center of the building. If we were the engineers of the Empire State Building we would reduced the size of the open floor design by, rather than using a center core steel column, we would use a skeleton steel frame. Also we would have used a thicker layer of concrete on the floor of about 2-3 inches.
The world trade center was an office complex with a 13.5 million square feet located in Lower Manhattan in New York City until September 11th 2001 when it was destroyed by terrorist attack. The blueprint of the World Trade Center was designed by M. Yamasaki as chief architect and Emery Roth & Sons as associate artichects, in 1962 through a tube frame design for the 110 storey building. The towers were constructed between the years 1966 1971.
The tube frame design allowed open floor plans instead of columns apportioned across the interior to support the tower load. The tube frames was protected by a spray on fire resistant material that provided a lighter structure which could move sideways when wind blew. Although this was the main cause of the collapse of the World Trade Center, this design is unlike the Empire State Building which was constructed using thick, heavy materials for fireproofing of the steel materials.
The World Trade Center was constructed with strong load-enduring steel columns that were closely located to each other to form a strong, tough wall design supporting all sideways weight, for example, wind weight and sharing gravitational pull. Beside modules were connected with the splices at the middle span of the column and spandrels.
The elevators, utility shafts, staircases, lounge rooms and other facilities were located at the center of the towers. The design included building veneer covered with aluminum alloy. The design used a system with sky lobbies where people could change floors from high capacity express elevators. This made the local elevator to located in the along the same elevator shaft. The towers were designed with narrow office window openings 18 inches wide.
If were the engineers in the World Trade Center we would propose the project to be put in a less congestion location since the serenity of the building was not appropriate, it disrupted traffic flow in Manhattan and many chaos. Also we would have changed the light weight bar joist as it could not sustain the load of the towers if exposed to an about ten minutes in fire. We would have put heavyweight bar joists.
The recent implementation of the Building Information Modeling (BIM) by the Dubai Municipality signifies a critical shift towards the improvement of construction practices across the region. BIM is currently associated with improvements in performance across the industry, including important enhancements of risk management practices. The following paper aims at researching the current state of BIM implementation in Dubai Municipality, identifying the most significant enablers of implementation pertinent to risk management, and locating the possible inhibitors of the process, with a list of suggestions intended to address the located inhibitors and thus maximizing the efficiency of risk management practices.
Research Goals and Objectives
The goal of the project is to outline the use of Building Information Modeling in the construction industry and to identify the benefits expected in the case of Dubai Municipality. Several objectives can be isolated in regard to the identified goal.
Explore the available literature in order to locate the evidence of successful implementation of BIM in the field of risk management.
Determine the applicability of the identified information to the case of the Dubai Municipality
Produce compelling evidence of the expected advantages of BIM for construction industry in Dubai
Identify the possible barriers to implementation of BIM and reaching its full potential.
Research Problem
The main goals stated by the authorities as reasons for the adoption of BIM are the reduction of costs related to the construction projects and the compliance with the strict environmental laws and regulations through reduction of the carbon imprint. However, the identified goals are to be considered as priorities since successful BIM implementation shows capacity for a range of related advantages, including the overall efficiency and safety. The latter option needs to be considered separately for two reasons. First, the construction industry shows the tremendous susceptibility to a diverse range of risks that include technical, construction, physical, organizational, financial, and socio-political, among others. Such diversity not only undermines the performance of the stakeholders but also compromises the well-being of the involved parties, which demands a definitive resolution. Second, the current rate of development in Dubai, as well as in the UAE on the whole, puts additional pressure on the construction industry in order to satisfy the growing expectations. Naturally, such dynamics increase the likelihood of undesirable outcomes and the emergence of risks. Since BIM is associated with an increase in safety, it is reasonable to expect the improvements both directly resulting from the update of the mandate and due to the broadened opportunities offered in the field of risk management. However, the degree to which the said benefits are applicable in the Dubai Municipality case is unclear. Therefore, it is necessary to determine the relevance of the opportunities offered by BIM in the field of risk management based on the available information.
Research Method
The method chosen for the paper is secondary research. The data utilized for reaching the designated goals is collected from the available literature on the subject. The main reason behind the choice in favor of the secondary research is the availability of the literature on the subject. BIM is currently widely adopted across the world, and its effects are studied extensively, which makes the required information readily available. Another reason is the relative approachability of the information, which does not require a significant allocation of resources and is not time-consuming, which is especially desirable considering the limitations of the project.
The scope of the research includes both the statistical and descriptive data. The former is necessary for obtaining reliable information on the benefits in question, and the latter is used to substantiate the findings and provide context for the information. The analysis takes the descriptive form since the accuracy and accessibility of the results retrieved via this method are sufficient for the identified goal.
The sources of data include existing studies on the applicability of BIM to the field of risk management, the assessment of benefits produced by the use of BIM, and the exploration of identified barriers to its implementation. In addition, the data on the results of the BIM utilization by the Dubai Municipality is incorporated in order to establish the connection to the located results and determine its applicability to the case. Data collection is limited to reputable sources such as articles from peer-reviewed journals, consultancy reports, and web sources by authoritative organizations and the government.
Enablers and Inhibitors of Best Implementation
Despite its growing popularity, BIM is not yet commonly accepted in the construction industry. The lack of customer awareness of the benefits associated with BIM implementation often stands in the way of construction companies that choose to use it. On the other hand, a growing body of evidence supports the fact of BIMs feasibility in the field of risk management. The following chapter provides an overview of the key enablers for implementation of BIM in risk management field and points out several important inhibitors pertinent to the Dubai Municipality setting.
Risk Management Overview
The construction industry is inherently prone to risks. To maintain the pace and uphold the quality of the project, it is necessary to implement a set of activities which allow identifying, analyzing, evaluating, monitoring, and addressing risks (Tomek & Matjka 2014). The risk is defined as an event that is characterized by dimensions of likelihood (the probability of happening) and consequences (the impact scenario), which can be collectively described as risk level (Tomek & Matjka 2014). Other important terms that need to be identified are risk owner, risk source, and risk recipient, as well as the context in which the risk is viewed, which can be internal or external (Tomek & Matjka 2014).
BIM has been shown to impact both internal and external risks in the construction industry (Zhang et al. 2013). However, it is worth pointing out that its influence differs depending on its presence in the segment. In the setting where it is already a relatively established practice, such as in European countries, it is considered a tool for risk mitigation as well as the creation of opportunities necessary for maintaining a competitive advantage. However, in a setting where it is relatively uncommon, such as in Dubai Municipality, it generates additional risks during the implementation phase. It is, therefore, important to recognize and utilize the enablers of successful implementation as well as identify possible inhibitors in order to address them.
Enablers of Implementation
Reactive IT-based Safety Systems
The informational technology capabilities offered by BIM offer means of detecting health and safety risks on construction sites, comprehensively assessing them, and mitigating them in time. Database technology is among the tools that ensure appropriate recording of and access to existing data on accidents. The previous experience of accidents provides an opportunity to conduct an analysis and identify the most likely hazards. A digital database combined with an analytical platform may evaluate risk distribution and give an overview of the most common risk factors occurring in any given field. Such information would be beneficial for risk management professionals as well as the customers who will be able to evaluate the competence of the chosen contractors. The online access to such database further increases the accessibility, offer submission possibilities, and establish communication channels. Another BIM tool that can be considered an enabler in the area of IT-based safety is virtual reality a computer-simulated visual representation of a certain environment that reacts to the interaction in a realistic way.
Within BIM, virtual reality is used to train workers in recognition of and appropriate reaction to the hazardous environments and situation without exposing them to the health risk. Aside from the potential improvements associated with the behavior modification and acquiring of the actual skills necessary for avoiding the dangerous situations, virtual reality is expected to provide the statistical data on the likely outcome related to a specific situation. Such data is important for assessing the likelihood of any given scenario, the readiness of the employees, and the expected improvement of a training session (Zhang et al. 2013). BIM-oriented virtual environment (BIM-VE) offers enhancements in information flow during an emergency situation as well as evacuation awareness (Zhang et al. 2013). Finally, the integration of data on common threats into a model of a project combined with the visualization of the construction site allows for a first-person inspection of the identified potential threats and hazardous locations. Finally, the integration of geographic information systems (GIS) into the BIM process allows for a much more precise assessment of the safety risks. The integration of GIS expands the scope of BIM to cover geospatial analysis, topography modeling, and real-time 3D editing, which significantly improves the accuracy of hazard identification in certain environments (Tomek & Matjka 2014).
Automated Rule Checking
The presence of well-defined rules and the possibility to monitor the compliance is a definitive component of risk management. However, their usage is traditionally connected to the inconsistencies of interpretation and application due to the manual approach, differences in comprehension, and reasoning capabilities. In the construction industry, the most important areas that rely on compliance with rules are related to compliance with building design and maintaining the safety regulations. The introduction of BIM allows encoding the rules in the format recognizable by computer software which then allows real-time and on-demand monitoring and verification of the compliance. The addition of the database of known common causes of accidents further broadens the possibilities of BIM by allowing estimating risk distribution on the design stage (Abbasnejad, Nepal & Drogemuller 2016). Numerous examples of using automated rule checking support the notion that BIM can successfully improve safety ratings of the project without significant resource allocation (Zhang et al. 2013).
Knowledge-Based Systems
The knowledge generated by previous experience in the construction industry can be valuable for prevention of future accidents as well as minimization of their potential occurrence. However, the volume of such databases and their diverse format places limitations on their effective utilization. In order to improve the results, the data is processed, systematized, and encoded in a computer-accessible form. The recent merge of the knowledge-based systems and BIM has created new opportunities that added the opportunity for managers to share the relevant information among employees. Such information is not limited to the processed bits of information and may include guidelines and suggestions built upon it. The use of knowledge-based systems can then be extended to cover the possible root causes of the risks and provide the most successful solutions using a risk-oriented module (Abbasnejad, Nepal & Drogemuller 2016).
Applicability to Dubai Municipality Case
According to Fadda (2014), the enablers of BIM implementation in the case of Dubai Municipality can be grouped into three categories policy, process, and technology. The latter two categories visibly align with the risk management-related ones presented above. For instance, all of the mentioned software vendors, such as ArchiCAD, Bentley, and Autodesk Rivet, are capable of the risk management functions such as real-time 3D modeling with location and highlighting of the identified areas of increased risk, limited virtual reality training simulation, and integration of automated rule checking. Fadda (2014) also mentions the communication capabilities of the BIM servers that allow synchronization of teams for improved coordination, which can be utilized for sharing managerial information retrieved via knowledge-based systems. Moreover, the levels 2 and 3 of the Capability Maturity Model (CMM) identified by Fadda (2014) are both necessary and sufficient for implementing a required level of safety. In addition, it can be argued that the consistent monitoring of risks and maintaining the desired level of safety is only possible through the incorporation of the four-dimensional design process (pertinent to Stage 2) and a seamless accessibility of all members of the project to the project model (necessary for achieving Stage 3) (Fadda 2014). Therefore, we can conclude that the majority of the identified enablers are applicable to the risk management in the construction industry of Dubai Municipality.
Major Inhibitors
Despite its growing popularity, BI still faces several barriers that threaten to inhibit its implementation. These barriers are traditionally allocated to three factors. First, the diversity of software solutions, the varying compatibility across versions and the inability to transfer data between platforms define the specificities of BIM functioning. Second, the organizational domain affects its efficiency through the presence and quality of training sessions, BIM operators, and managerial activities. Third, awareness, motivation, perceived value, and willingness to implement BIM form an attitude towards the technology. In the risk management segment, BIM is still poorly recognized, and its benefits are only superficially understood. Besides, the regions where BIM is in the early implementation phase, it is reasonable to expect the lack of skilled staff.
Dubai-Specific Inhibitors
A study by Mehran (2016) examined the process of BIM adoption in the UAE following the mandate of 2015. Three main inhibitors were identified by the researchers. First, BIM failed to present a unified set of standards. Second, there was insufficient understanding of the benefits associated with BIM implementation and the feasibility of the technology in the light of the cost of its implementation. By extension, many vendors and individuals demonstrate resistance to change towards BIM, which is identified as a separate factor (Mehran 2016). In addition, it should be pointed out that currently the Mandate specifies several criteria of BIM application, and although the criteria were significantly expanded in a 2015 revision of the Mandate, such approach still cannot be deemed encompassing. Therefore, we can conclude that the identified inhibitors are associated with the organizational and attitude factors, where the former include the incomplete coverage of construction projects as well as the deficiency of the robust standards, and the latter are represented by the inaccurate perception of the benefits offered by the program.
Suggestions for Improvement
As has been shown in the previous section, the enablers of BIM implementation for risk management in Dubai Municipality reside mostly within the technological domain, and the most prominent inhibitors are either organizational or perceptional in nature. Therefore, the following list of suggestions can be outlined.
Encompassing Regulations
Currently, the mandate that encourages the implementation of BIM covers only a certain segment of Municipalitys projects. This means that the BIM adoption is still fragmentary. Therefore, a more encompassing approach must be pursued that would eventually include all projects and encourage BIM usage in a holistic rather than piecemeal manner. It should be noted that the most recent additions to the mandate are consistent with this recommendation since they add the criterion of a governmental project to the list of facilities pertained to its application and decreased several other metrics, such as the number of floors from 40 to 20 and the area from 300 to 200 thousand square feet (Mehran 2016). It is, therefore, logical to conclude that improvement in this area is underway, which should be acknowledged by the stakeholders.
Policies Unification
Due to the fact that BIM implementation is in the early stage, the construction companies work on the implementation of policies and standards that regulate various aspects of its use. However, as pointed out by Mehran (2016), these efforts are disparate and may eventually contribute to confusion rather than convenience and transparency. Therefore, in order to improve consistency in BIM implementation and eliminate the possible setbacks associated with discrepancies, it is recommended to establish and maintain the unified standards and develop the policies accordingly. Admittedly, the most viable way of unification of the said policies is the coordinating effort of the administrative entity such as the Dubai government. Therefore, it is suggested to implement the encouraging initiatives that would promote collaboration across the industry and result in improved safety and cost-efficiency.
Raising Awareness
As was pointed out, the advantages of BIM for risk management are understood insufficiently by the construction industry managers in the Dubai Municipality (Mehran 2016). The knowledge is often partial, and the excessive cost of BIM technology is often viewed without the acknowledgment of opportunities it provides for saving resources. Thus, it is recommended to develop a series of events aimed at improving the understanding of the process and the advantages offered by automation, database functionality, and employee training. It is also worth pointing out that despite the growing recognition of BIM, the sources of information on the technology are currently limited to the U.S.-based and European journals, where it is already firmly established. Consequently, only a limited amount of research exists that illustrates the applicability of BIM to Dubai Municipality setting. Thus, it is suggested enabling the researchers to facilitate studies of BIM-related risk management practices and associated benefits. It is also highly desirable to establish a local publication that would inform on the developments in the area and improve understanding among the stakeholders.
Training
BIM is a complicated system and requires sufficient training as a necessary condition of successful implementation. For this reason, most of the vendors which offer BIM-related technology provide training services for the staff. However, the current learning curve is considered too steep by most respondents (Gerges et al. 2017). Such situation is especially undesirable for levels 2 and 3 of the Capability Maturity Model (CMM) identified by Fadda (2014), which require both horizontal and vertical cooperation between employees and equal access to the system. Thus, ways must be sought of providing a more accessible training not only to high-level operators and administrators but to all participant of the project that can benefit from risk management capabilities offered by BIM systems.
Resistance to Change
One of the issues identified by Mehran (2016) is the reluctance to implement BIM in the construction projects observed in some companies. This factor is a common occurrence among entities which are subject to change. Consequently, the phenomenon is well-understood and a multitude of methods of addressing it exist in the literature. The suggestion, therefore, is to apply the most effective solutions since they are expected to be sufficiently compatible both with the Dubai Municipality setting and the construction industry.
Conclusion
The current pace of development in the construction industry of Dubai Municipality creates additional risks and puts additional pressure on the risk management segment. The evidence gathered in the process of the research points to the high viability of BIM as a tool for project risk management and suggests applicability of the identified enablers to the Dubai Municipality case. However, in its current state its performance is inhibited by resistance to change, lack of unified standards and/or policies, and insufficient awareness associated with scarcity of relevant sources. Therefore, it is suggested to facilitate the development of unified standards, provide more accessible training, raise awareness of BIM benefits, and establish relevant sources of information. The suggested developments are expected to create safer workplace environments, enhance employee safety training, and increase the accuracy and reliability of risk management modeling within the industry.
Reference List
Abbasnejad, B, Nepal, M & Drogemuller, R 2016, Key enablers for effective management of BIM implementation in construction firms, Creating Built Environments of New Opportunities, vol. 1, pp. 622-634.
Fadda, H 2014, Implementation of BIM within construction projects in Dubai, MSc Dissertation, Heriot-Watt University.
Gerges, M, Austin, S, Mayouf, M, Ahiakwo, O, Jaeger, M, Saad, A & Gohary, T E 2017, An investigation into the implementation of Building Information Modeling in the Middle East, Journal of Information Technology in Construction, vol. 22, no. 1, pp. 1-15.
Mehran, D 2016, Exploring the Adoption of BIM in the UAE Construction Industry for AEC Firms, Procedia Engineering, vol. 145, pp. 1110-1118.
Tomek, A & Matjka, P 2014, The impact of BIM on risk management as an argument for its implementation in a construction company, Procedia Engineering, vol. 85, pp. 501-509.
Zhang, S, Teizer, J, Lee, J K, Eastman, C M & Venugopal, M 2013, Building information modeling (BIM) and safety: Automatic safety checking of construction models and schedules, Automation in Construction, vol. 29, pp. 183-195.
The advent of the 21st century saw a paradigm shift in the manner in which governments, civil society, and scientists perceived global warming. This greater awareness trail blazed a situation where sustainability in almost every industry was a clarion call. In infrastructure, it was not business as usual. Economists warn of depletion of natural resources in light of an ever-growing world population and human destruction (Chandratilake and Dias, 2013).
In the recent past, there have been numerous improvements in the worlds sustainability agenda. Countries and regional bodies have set objectives to promote the reduction of Green House Gas (GHG) release as a matter of urgency. To arrive at this target, progressive building industry principles have been adopted concerning building operations, design, and performance to solidify achievements of sustainability. From this perspective, it is crucial to develop an adequate green building-rating tool in Australia that meets international environmental building standards.
While many rating agencies have developed standards for use in the construction industry, there is hardly any resemblance. Green star has an important role to play in helping Australias building market to internalize undesired effects on the environment and, consequently, to accomplish more sustainable infrastructures. Furthermore, the strength of the Australian economy, in comparison to the rest of the developed economies, sets favorable conditions to encourage higher levels of capital investment and sustainable development in the infrastructure sector. Other national agencies play similar roles albeit using slightly different standards. Does this mean that Green Star is inferior considering the popularity of the other comparable agencies such LEED and BREEAM? The study indicates that to be untrue and further sanitizes the act. Consequently, this work will argue that improving the standard for Green Star rating system is fundamental in order to achieve higher grades of environmental performance and speed up competitiveness in a consistently dynamic global economy.
Nomenclature
Green building rating system: Green Star is a quality benchmark designed to grant accreditation to building projects in design and construction to enhance sustainability.
Sustainable building: Sustainable building is a concept in that instills minimalistic environmental impacts through sustained and documented principles in the building, construction, and architectural industry.
Green Star: Green Star is Australia has trusted standard for sustainable building and construction whose rating tools comprehensively encompass public and private institutions.
LEED: LEED is the largest US largest green building-rating tool with slightly different approaches for Green Star but whose aims and intentions are similar.
BREEAM: BREEAM rates and develops standards for sustainable building in United Kingdom. Similarly, it has developed rating tools that span all sorts of constructions with the aim of reducing emissions and enhancing probity in resource usage.
Australia Green Building Council: A not for profit industry association that drives the adoption of green building practices in Australia.
Introduction
Project Definition
To be sustainable, buildings should take optimal and responsible resources from the environment in terms of and ensure durability. Sustainable development is increasingly highlighted because the buildings have a constantly increasing impact on the environment in terms of resources uptake during construction and inordinate emissions detrimental to the environment. This project analyses Green Star rating scheme; which is prepared in order to identify weaknesses (i.e. in comparison to international standards LEED and BREEAM); and to identify ways to popularize sustainable building practices in Australia through encouragement of improvement of Green Star. The weaknesses may be tackled by structural readjustments that will also be discussed.
Project Goals
To benchmark the rating criteria that Green Star uses in order to assess and grant accreditation in the building stock in Australia. To concentrate specifically in the comparative analysis of the major building rating tools: LEED (Leadership in Energy and Environmental Design) and BREEAM (Building Research Establishment Environmental Assessment) from the United States and United Kingdom Green Building Councils, respectively.
To propose course of actions in order to make a significant enhancement in Green Star rating tool. More particularly, to identify weaknesses in Green Star scheme and suggest more adequate responses.
How the Project will benefit
This project will contribute towards the betterment and enhancement of Green Star rating scheme with the aim of promoting leadership in the development of sustainable building stock in Australia. More specifically, benefits for the building industry will be in the shape of innovative design and construction. The project aims to boost Australias standing in OECD countries in relation to sustainable construction and environmental performance. Additionally, the project may make a stronger case to allow for smoother transition towards a demanding regulation that advocates for a low-carbon economy. At the same time, benefits for the Australia community may be economic (i.e. employment, companies bottom line, investment and economic growth) environmental (i.e. reduction on GHG emissions, energy efficiency and use of less damaging construction materials) and social (i.e. healthcare stakeholders, community development)
Project Deliverable
The project deliverable will result in a course of action for Green Star rating towards the development of environmental criteria that favor the reduction in GHG emissions, the execution of a Life Cycle Assessment (LCA) in construction materials and higher levels in energy efficiency. At the same time, the project will deliver recommendations on Green Star rating in order to produce a more comprehensive assessment based on the consideration of a two-staged accreditation process: design review and construction review. On the other hand, improvements in the bottom line for companies under Green Star certification, via reduction in building operation costs and higher return on investment via an increase in property values and more tenant attraction.
In addition, a reduction in environmental and social impacts in the building stock sector in Australia. More specifically, community and workers will have access to healthier places to live and work.
Review of Literature
Introduction
There is a shift in all industries towards environmental friendly operations. The housing and construction industry has also been affected by this trend. People want houses that have the minimum possible negative influence on the environment. Global warming and the resultant climate change have caused consumers to be more conscious in their purchasing (Johnson, Whittington & Scholes, 2011). Companies are now forced to invest heavily in Research and Development to create innovative green housing solutions. Such innovations could reduce the amount of waste sent to landfill, increase recycling, create energy efficient homes and create renewable energy. The current industry leaders are also leaders in innovation and environmental consciousness (Portalatin, Koepe, Rostoski & Shouse, 2010). There are various certifications and awards issued annually to encourage this trend. Companies literally compete for these since it proves to consumers that they are doing something about the situation. The Code for Sustainable Homes in the UK, Australia Green Building Council in Australia among others world over, serve this purpose. Many industry players have adopted this principles based approach (Johnson, Whittington & Scholes, 2011). However, the effectiveness of the props (Green Star, LEED, and BREEAM for instance) in serving this purpose is questionable (Portalatin, Koepe, Rostoski & Shouse, 2010).
Literature Review
Garnaut (2011) indicates that the building sector contributes immensely towards Greenhouse Gas (GHG) emissions, utilizing approximately 40% of the worlds energy and producing approximately 30% of the carbon emissions. These figures are the largest of any single industry globally as of 2011. At the same time, sustainability has become the buzzword of the academic and the business fields. In particular, it is possible to identify two large trends in the development of sustainable infrastructure in the last decades (Hall, Daneke, & Lenox, 2010). As noted above, the catchphrase is affecting the consumer markets in construction with consumers favouring environmentally friendly companies en masse (Johnson, Whittington & Scholes, 2011).
The Period 1990 2000: the start of the 1990s puts large emphasis in sustainable design, which was also joined, to the notion of buildings being eco-friendly , environmentally friendly and unobtrusive . A crucial element for building performance during this phase was founded on a cost efficient evaluation (Hall, Daneke, & Lenox, 2010). According to Portalatin, Koepe, Rostoski & Shouse (2010), cost effectiveness was the sole competitive arena in light of burgeoning industries world over occasioned by growth in economies. Global warming occasioned by carbon emissions were not a critical factor to governments. Only scientists were concerned (Roodman & Lenssen, 1995).
The Period 2000 2010: the start of the 21st century reveals the beginning of calculating carbon and measuring efficiency . This phase has established the measurements of CO2/m2/year as common factors in environmental evaluation of buildings. The principal indicator on building performance during this phase was based on measuring carbon emissions (Hall, Daneke, & Lenox, 2010). Governments had also joined the clamour for suitable construction through legislations especially in the developed world. Credible research had also indicated a trend where massive chunks of the housing market appreciated sustainable solutions, as global warming became a possibility. The world resources were on the verge of depletion in light of burgeoning populations (Johnson, Whittington & Scholes, 2011).
The sustainability phenomenon has resulted in an abundance of green building rating tools and frameworks around the world to evaluate property development against a collection of sustainability criteria . Green Building Councils are members of the World Green Building Council; and on its respective country are conformed by partnerships between government and private organisations that have worked in collaboration to develop Green Building rating tools. Internationally the most widely recognised rating system includes LEED, BREEAM, Green Star, CASBEE, SICES and EEWH. The sustainable building industry is shaped by the influence of the mentioned rating tools, which are mainly endorse and applicable through diverse Green Buildings Councils around the globe. Which are, LEED in the US Green Building Council (USGBC), Canada Green Building Council, Brazil Green Building Council, India Green Building Council; CASBEE in Japan; BREEAM in the UK Green Building Council; SICES in Mexico Green Building Council; EEWH in Taiwan Green Building Council and Green Star in the Green Building Council of Australia (GBCA), Green Building Council of New Zealand (NZGBC) and in the Green Building Council of South Africa (GBCSA). Although, there are many others international building tools available, the three larger rating systems in the world are LEED, BREEAM and Green Star.
Research by Dirlich (2011) demonstrates substantial disparity in terms of the global methodology (i.e. LEED, BREEAM and Green Star) to be applied in order to evaluate sustainability criteria in the building sector. This project further progresses the demonstration in subsequent sections as clear and arguably critical reasons emerge to support these differences. This discrepancy can be explained by several factors; perhaps one of the most influential is the fact that each of the rating systems was conceived and adapted to a specific geographical context that regards unique characteristics in terms of environmental conditions, politics and legislation, industry sector and socio-economic structures. For instance, BREEAM methodology is tailored, and therefore, better applied and representative when assessing the sustainability performance of the building industry in the United Kingdom than anywhere else in the world (Dirlich, 2011). Adaptation of a generic rating may also contribute to apathy in governments and demographics that are yet to ingratiate sustainability solutions. The concept, aims, and noble causes of the whole sustainability endeavour ought to be communicated world over, but development of systems upon which to implement it left to specific geographic areas notes Dirlich (2011). However, certain platforms or benchmarks may highlight the crust upon which to develop.
Furthermore, the topics for building assessment vary according to different weightings and categories. LEED 2009 grants an overall score of 110 points with a weighting system that considers 23.6% to sustainable sites, 9.1% to water efficiency, 31.9% to energy and atmosphere, 12.7% to material and resources, 13.6% to indoor environmental quality, 5.5% to innovation and design, and 3.6% to regional priority. The overall score for BREEAM 2011 goes up to 110% and its weighting system considers: 10% to land use and ecology, 6% to water, 19% to energy, 12.5% to materials, 15% to health and wellbeing, 8% to transport, 7.5% to waste, 10% to pollution, 12% to management and 10% to innovation. The overall score for Green Star 2013 is 100 points and its weighting system considers management, indoor environment quality, energy, transport, water, materials, innovation, emissions, and land use and ecology. These building weighting aspects are not fixed like LEED and BREEAM, as they change according to states and territories in order to consider diverse environmental priorities across Australia. For example, potable water has a high relevance in South Australia than the Northern Territories, and consequently the water category has a higher weighting in South Australia.
Therefore, it can be argue that a customized building rating system will be more representative and meaningful in addressing the specific context and particular requirements of the building sector in a determined country, state or territory. However, on doing this, drawback effects appear as international comparison becomes more difficult because multiple rating tools are built upon different categories and weightings. According Dixon et al. (2008), the proliferation of rating tools around the globe has created market distortions that prevent stakeholders and property investors from having a clear understanding on the implications of different sustainability methodologies. In this regard, Reed et al. (2009) point out that while it is established that states and territories possess unique characteristics, the objective of reaching a global rating tool can be achieved in a similar way. According to him, financial methodology works for analysing property values in different countries: by using a twelve-year discounted cash flow technique that considers exchange rates fluctuations, it is possible to contrast the value of an office building in Berlin directly, London, New York City, or Melbourne. In other words, a straightforward approach that relies on developing a global rating system will deliver important benefits that will facilitate the access to transparent information in the form of sustainability features and building assessment around different countries. The underpinning reasons behind not having a global rating system can be attributed to lack of knowledge and willingness to compromise towards a single rating tool since it may not be the possible best tool applicable to a wide range of states and territories. Additionally, a global rating system would not necessarily be a good solution. It is instructive to note that customization of a rating system to geographical locations, purpose of the building, legislations, cultural inclinations and resource availability is trendier than a blanket system. For example, Australia and Britains resource endowment may posit a situation where Australia does not need strict rating systems as opposed to Britain. Hence, a generalist rating system will critically disadvantage Australians.
Many developing countries have not adopted rating systems. In Africa, over 90% of the countries do not have a national rating system for construction. Going forward, as more countries embrace the need for sustainability, it will be hard to roll out a uniform Rating System considering the richness of culture in the continent. Such countries will have to grapple with a nationally developed system that will specifically cater to the cultures of its citizens. Otherwise, as noted by Olgyay & Seruto (2010) sharp divisions may emerge between governments, locals and human rights organizations, which may not serve the intended noble cause.
In an attempt to attain sustainability in building, the steps have been categorized into the first, second, and the third wave. The first wave is a reference to a group of companies that were opposed to the notion of sustainability. Birkeland (2012) provides the highly effective perspective on the natural environment and the employees. The culture of exploitation was synonymous with the first wave organizations and this was largely to blame for the failure to achieve sustainability during the time. Organizations in this era were opposed to green activists and the governments attempts to bring about policies that would cater for sustainability in building (Olgyay & Seruto, 2010). The community was distanced from the sustainability debate with its claims being labelled by the organizations as illegitimate; this development reveals the less regard the organizations of the first wave gave to the community and the environment (Department for Communities and Local Government, 2010).
According to Shove (1998), organizations in the first wave were characterized by ignorance in the form of non-responsiveness. This greatly hindered and dissatisfied any attempts to achieve sustainability in building. Primacy was given to technological and financial factors with less regard being reserved for environmental factors. Ignorance came in a higher degree as the workforce was condemned to be compliant of decisions made and business was conducted as usual. In the light of this, organizations during the first wave regarded environmental resources as free goods requiring little attention (Green Building Council Australia, 2012).
Shove(1998), reveals that the motivation to move to the second wave stemmed from the perceived need for organizations to be compliant to legal, environmental, safety, and health requirements and the numerous expectations of the community. Business opportunities during the second wave aimed at avoiding the huge costs of failing to comply with the stipulated standards. Moreover, there was the increased need to create an efficient system to mitigate risk. The objectives of the organizations in the second wave were to eliminate waste progressively and increase efficiency in materials and processes. The second wave was synonymous with increased attempts for reorganization and waste reduction (Harmelink et al., 2006). Three paths catered for efficiency in this era. These were; cost reduction, improving quality through value addition, and flexibility and innovation through the advantage of the first mover (Gann, 2000). An example of efficiency attained in the second wave was eco-efficiency, a concept that converged at the use of fewer resources to attain more. This was attained through the delivery of goods that were competitively priced and services meant to satisfy the numerous human needs and foster equality in living standards (Hawkes, 1993). All these developments were achieved by reduction of ecological impact and the intensity of the resources throughout the life cycle to a level that was in line with the carrying capacity of the earth. Core eco-efficiency principles fostering efficiency in building sustainability during the second wave were reduction of material intensity, minimization of energy intensity, reduction in the dispersion of harmful substances, recycling, capitalizing on renewable resources, extension of product durability, and increased service intensity (R.S. MEANS, 2011). Countries resource endowments are critical too. For instance, land bank (refers to the amount of land a company has that is available for construction) represents capacity to expand. Land is also an asset, which appreciates. The more land in the land bank, the higher the value of this asset (Hawkes, 1993). Certain cities, municipalities, countries and regions face an acute shortage of this commodity. While the noble cause for sustainable solutions in construction applies to all, it would be direr to apply it in such departments (Jaraminiene, Bieksa, & Valuntiene, 2012). These places also experience exponential growths in populations, which multiplies this need. Examples include China, India, Indonesia, large parts of Asia and Japan. The worlds receding coastlines will have dire consequences as regards this asset. Hence, it is impractical to universally apply rating systems because the parameters (management, indoor environment quality, energy, transport, water, materials, innovation, emissions, land use, ecology etc) are not universal (Jaraminiene, Bieksa, & Valuntiene, 2012).
As opposed to the first and the second wave, the third wave was synonymous with numerous achievements in building sustainability. The companies in this era went green. The need for understanding the motives behind ecological responsiveness in the corporate domain is for a number of reasons (Bell, 2000). First, such an understanding is vital in helping organizational theorists to predict behaviours related to ecology. For example, if the corporations adopted practices that were ecologically responsive with the view of meeting legal requirements, the firms would engage in activities that would be in line with the legislation (Jaraminiene, Bieksa, & Valuntiene, 2012). Second, the understanding would expose mechanisms that would foster organizations with ecological sustainability. Such an attribute would allow managers, researchers, and policy makers to assess control mechanisms and command efficacy, voluntary measures, and market measures (Roodman, & Lenssen, 1995).
More closely related to the building development sector, in the last two decades there has been a significant evolution in the way rating tool methodologies assess the building sector. In the beginning of the 1990s, the first rating tools techniques were developed (i.e. BREEAM) with a main focus in design stage, whereas the actual construction was not so important (Sustainability Building Australia, 2013). At the start of the 21st century, this trend has gone in reverse, where most Rating Tool methodologies show significantly increased concern in the actual construction and a less focus in merely building design (Sustainability Building Australia, 2013). At the same time, since 2006 a new trend in green building rating has risen, where the focus is now on the form of sustainable performance. This recent performance trend has expanded the implications of sustainable buildings, in an attempt to establish as a common practice for the infrastructure sector the measurement, through international audit and standards, of the levels of Green House Gas (GHG) emissions, energy and water footprint. As the orientation in direction to the construction stage and sustainable performance expands in time, the rating tools methodologies will accommodate accordingly, shifting increasing categories and weighting from building design perspective to building performance. Hence, this will have a powerful effect on the future configuration of the building sector.
In addition, one important issue that also has a significant impact over the lack on global consensus on sustainable buildings is that the world most accepted technology rapidly becomes the benchmark and, consequently, there is no much space to include new breakthroughs. In this direction Cur well and Cooper (1998) point out that because the notion of sustainable development is continuously evolving (i.e. in terms of conceptualization, implementation and monitoring) whereas building standards remain within their respective sustainability frameworks, there is an essential constraint to reach global agreement. At the same time, Dovers (2002), Godfaurd (2005), and Kibert (2003) sustain that this quest for global agreement is disregarding insightful knowledge that could be put in practice in the sustainability field. The global impact of technology cannot be underrated. Countries capable of successfully measuring CO2 emissions per square metre of a building effectively and successfully must have a certain level of technology penetration. As Godfaurd (2005) notes some countries, do not have structures to indentify households effectively. Additionally, there exists no regulation to monitor construction of houses. Implementing a rating system that heavily depends on these factors is a monumental task.
Research in Current Solutions
Sustainability rating methodology varies considerably, from one tool rating system one to another. Measurement of building performance, scope and environmental criteria within the infrastructure sector are some of the factors that distinguish some of the most accepted and common global rating systems in the current sustainable building industry (i.e. LEED in United States, BREEAM in Britain and Green Star in Australia). The three rating systems are similar in aims, approach and structure to rate the performance of the building sector and create according grade levels for accreditation (Sustainability Building Australia, 2013).
BREEAM is a rating tool introduced in the United Kingdom in 1990 has an extended record of accomplishment that is mainly applied in the UK. The system applies in a number of building infrastructures such as retail, schools, industrial offices and homes. The BREEAM scheme buildings score awards a Pass , Good , Very Good and Excellent rating based on the general score (Fowler and Rauch, 2006).
While taking into account all areas in the building industry and not just the simple mandate of cutting down on carbon emissions, BREEAM seeks to provide a sustainability strategy adaptable world over but specific to Britain problems and settings (Sustainability Building Australia, 2013). The principal criterions for sustainable design and construction under BREEAM include management, health and wellbeing, energy, transport, water, materials, land use, ecology and pollution. BREEAM offers a comprehensive approach whose goal is to minimize environmental impacts in the different stages of construction and building operations. Hence, there are multiple environmental and economic benefits on adopting the BREEAM system in the building industry such as: access to lower energy requirements and building operational costs, higher property rent value, enhancement in productivity levels due to workers access to a comfortable working environment, improved reputation for the building industry that commits to environmental protection, shorter selling times in buildings, and other publicity benefits.
Although there is an extensive record in the Building sector that is achieving high levels of accreditation in the BREEAM rating systems as their core sustainability strategy, the implications of the rating tool are not considered by U.S. design professionals (Reed, Bilos, Wilkinson, & Schulte, 2009). Perhaps, the major constrain in the BREEAM rating system is that in spite of its contribution towards sustainable design and construction, it is not as widespread as LEED, and only selected as the favourite rating system by the building industry within the boundaries of the UK. However, its application and success in UK and it is not so stellar success outside UK highlights the possibility of success of nationalist approaches to sustainability.
Further leading credence to geographically specific sustainability solutions is Leadership in Energy and Environmental Design (LEED). LEED is a system-rating tool that was created by the U.S. Green Building Council (USGBC) and is more globally recognized as a reference for sustainable building practices. Furthermore, not only in the United States but also in a multiple number of different countries around the world, LEED accreditation is the most commonly accepted standard for assessing building sustainability performance (Lee, & Burnett, 2007). The system forms the platform on which countries that have not adopted sustainability base their rating systems on adoption.
The LEED green rating system is administered by the U.S. Green Building Council. Its aim is to promote design and construction practices that increase profitability. It also reduces the negative environmental impacts of buildings and improving occupant health and well-being.
LEED employs a more subtle approach and is somewhat generic. However, it has progressive nuggets that differentiate it from the rest. The most remarkable economic incentives granted by LEED are among the following: 8% to 9% decrease in building operating expenses, 7.5% increase in property values, 6.6% improvement in return over investment, 3.5% augment in tenancy, 3% rent increase. The construction cost is also an important advantage because the large majority of buildings are capable to achieve LEED certification without requiring additional funding. Some do need extra funding, but only for specific features, such as photovoltaic. In addition, comparative costs advantage in adopting LEED rating systems are given where LEED buildings are globally recognized, hence enjoy a greater reputation, and incurred on a similar cost (i.e. cost per square meter) than what it takes to adopt alternative building system rating methodologies.
LEED building rating scheme has four certification categories for buildings. They include Certified, Silver, Gold and Platinum. The grade of accreditation depends on the score achieved in five fields of assessment: sustainable sites, water efficiency, energy and atmosphere, materials and resources and indoor environmental quality (Lee, & Burnett, 2007).
In particular, the evolution towards the implementation of Green Star rating system in Australia can be regarded because of the escalating pressure of environmental legislation. In this manner, Fisher (2001) points out that there has been a great response coming from several infrastructure developers in Australia to seek Green Star accreditation for their recent constructions. The fact is that over 4 million m2 have turned into Green Star certified space around Australia.
However, two environmental rating frameworks are present in the building sector of Australia: NABERS (i.e. National Build Rating) and Green Star scheme from the Green Building Council of Australia (GBCA). Each of these rating schemes aims to evaluate several parameters in order to reward with a number of stars. The amount of stars awarded is different in the two schemes, with NABERS giving up to 5 stars and Green Star up to 6 stars. NABERS has an environmental criterion in energy. It was previously known as the Australian Building Greenhouse Rating. On the other hand, the environmental standards under Green Star include management, indoor environmental quality, energy policies, transport orientation, materials use, land use and ecological orientation, and emissions.
Table 1: Comparison Table by Category Weighting. (Source: BRE 2008)
BREEAM
LEED
Green Star
Management
15
8
10
Energy
25
25
20
Transport
25
25
10
Health and Wellbeing
15
13
10
Water
5
5
12
Materials
10
19
10
Land use and Ecology
15
5
8
Pollution
15
11
5
Sustainable Sites
16
Although the council methodology of the United States Green Building Council (USGBC) and the Green Building Council of Australia (GBCA) varies considerably, their rating systems do allocate a number of resemblances. For instance, both rating systems have minimum eligibility criteria and demand certain prerequisites for certification, both have taken an approach of collecting up credits under a type of category and both institutions have credentials in place to promote the active participation of certified experts in their respective rating systems.
According to Reed, Bilos, Wilkinson, and Schulte (2009) by doing a benchmark analysis on the different categories and weightings parameters for the rating tools LEED, BREEAM and Green Star, the methodologies can be directly comparable. Reed, Bilos, Wilkinson, and Schulte (2009) reach some important conclusions, by analysing different aspects on the rating tools.
LEED and BREEAM also reach a higher standard than Green Star in terms of energy efficiency. This is because LEED and BREEAM schemes take into account a larger number of parameters for assessing the building performance based on two comparable building models (Sustainability Building Australia, 2013). On the contrary, the Green Star ratings system predicts building performance from one single building model. The model has fewer parameters for assessment. Therefore, Green Star is not as effective in the evaluation of energy efficiency rating scores. BREEAM performs better in building management when compared to LEED and Green Star.
Again, in comparison to the other scheme methodologies, Green Star falls behind in the category of Pollution. However, since water scarcity is an important sustainability issue in Australia, the water preservation standards of Green Star are consistently higher than LEED and BREEAM. In regards to land use and ecology BREEAM appears to be setting the greatest emphasis, which is coherent to the current infrastructure scenario in the UK that presents high levels of density population. To some extent, this analysis shows how the major rating tools LEED and BREEAM are better adapted than Green Star to asses sustainable performance in the building sector in terms of energy and emissions, and consequently, offer a better response to this local sustainability issues where the respective frameworks were initially originated.
Another important difference between these three major rating tools (i.e. LEED, BREEAM and Green Star) can be found in terms of category weightings (referenced in Figure 1). This rating methodology gap, based on Green Star categories, is displayed in the figure 1, where the identified areas of contrast that resemble most significant differences, between Green Star and the alternative LEED and BREEAM are: water, materials, emissions/pollution and land use and ecology.
Figure 1: Category Weightings (Source: Green Building Council Australia)
In addition, since the LEED rating system is applied in multiple building projects around the planet, it can be argue that this methodology is more adjustable to a broad range of scenarios. For instance, assessing an airport), whereas Green Star requires the development of a custom rating system for project types not covered by their current tools (Sustainability Building Australia, 2013).
Undoubtedly, there are gradual and significant differences between LEED and Green Star system ratings. For instance, LEED applies an environmentally friendly method (i.e. online system) to submit records and documentation, whereas Green Star initiative for submission is through paper and CD. The submission stage is a long process that can involve thousands of pages of documentation. However, the greatest discrepancy can be found in the technique in which the buildings industry gets accreditation. In LEED, the procedure for accreditation is two staged: design review and construction review. The building projects can obtain expected score at the end of the design stage but will only be given certification at the end of the construction stage. LEED approach secures the execution of the initiatives acknowledged in the design stage. However, in comparison to LEED, Green Star rating system has a loop hole in this situation, since it is feasible to obtain accreditation at the stage of design, and then execute the project in an entirely different manner. In an attempt to solve this issue, Green Star now offers a number of As-Built ratings (to assess the consistency of the design stage during building implementation). In addition, the Green Building Council of Australia (GBCA) is also commanding a time limitation on the promotion of design certification.
However, as it is illustrated in the Table 2: Green Star Certified Office Buildings, the introduction of As Built ratings is not sufficient to secure sustainable building practices. This premise is applicable for all states and territories except for South Australia, where out of ten design-certified office buildings four office buildings have passed through As Built certification such as 40 per cent rate (Green Building Council Australia, 2012). However, for the states and territories of Victoria, New South Wales, Queensland, Australian Capital Territory and Western Australia the situation is more shocking since once that design accreditation has been granted a much smaller proportion (i.e. 5 per cent) of Green Star certified office buildings opt for accreditation at the construction stage (Sustainability Building Australia, 2013).
Table 2: Green Star Certified Office Buildings. Source: Warren, C. M. Who needs a Green Star? (2009) UQ Business School
Office Design
Office As Built
State / Star Rating
4
5
6
4
5
6
VIC
5
16
3
NSW
8
6
3
3
SA
2
7
1
2
2
QLD
10
10
2
1
ACT
2
2
1
TAS
1
1
0
NT
0
0
0
WA
4
2
1
Total
32
44
11
2
6
0
On the other hand, carbon emissions from building are projected to grow over the next 25 years by an annual rate of over 1% (Garnaut, 2011). The contribution of building to the increase of carbon emissions when combined with other sources of carbon emissions such as industry and transportation result in an even higher rate of carbon emission (United Nation Environmental Program, 2009).
The great concern over carbon in the atmosphere is the characteristic of carbon in the form carbon dioxide to trap heat within the atmosphere leading the phenomena known as global warming. Increased temperature in the atmosphere will result to an increased rate of ice melting at the poles, stronger cyclones, and tornadoes, the faster spread of deserts and ultimately increased emissions as building attempt to maintain a conducive environment for working and living within the building environment. The most significant factor that contributes to the high rate of carbon emissions in buildings is the consumption of electricity (Dunphy, Griffiths, & Benn, 2007).
When other attributes of a building are considered, the result is an even higher carbon emission. Buildings have a life span of 50 to 100 years and through this period; the building emits carbon to the atmosphere. It is estimated that if new commercial buildings were built to consume 50% less energy 6 million tons of carbon dioxide would be reduced from the high contribution of buildings (Better Buildings Partnership 2010). To get a good impression of this, it can be equated to removing 1 million cars from the road annually. Without the considerations of the building environmental performance, and seeking out ways to improve this performance building will be a great contributor to the increasing carbon emissions (Ramanathan, & Carmichael, 2008).
Building more environmentally friendly building is referred to as building green. Building green not only reduces the carbon emissions of the building but also results in savings and the general improvement of the bottom line. Some of the ways that a building can be made more efficient include using the most efficient electronics in the building construction to improve performance. Some of these systems including the building heating and cooling systems, another is taking advantage of the daylight to reduce the need for lighting. The primary ways in which the building meets the minimal carbon footprint emissions is through ecologically responsive design and improved energy competence (Jaraminiene, Bieksa, & Valuntiene, 2012).
The general argument in favour of more energy competent buildings is that greener building is cheaper to run and provide a better environment for the occupants. In Australia, electricity accounts for 89% of the total carbon emissions. Electricity in Australia is produced from brown coal, which is found in abundance in the country. A change from this to using gas as a source of electricity would greatly reduce the carbon emissions. This is however not likely to occur considering the social-political conditions. The current efforts focus on the performance of the building and how specific it utilizes energy. The consensus is that the improvement in the thermal, day lighting and natural ventilation of a building would significantly improve the energy efficiency of the building and thus the carbon footprint (Taylor, 2010).
Governments in developed nations have started programs that are geared towards increasing the energy efficiency of existing building and those being built. In order to achieve the best possible standard a comparison of these programs must be done to determine the area each encompasses. Recent research has shown that the Australian program green star is significantly behind those of other developed nations such as the United States and United Kingdom (Agreening, Greene, & Difiglio, 2000). The research however does not specify the sectors in which the program lags behind and how best this challenge can be tackled. Consequently, this research seeks to fill this gap in knowledge (Roodman, & Lenssen, 1995).
Lighting, air conditioning and ventilation account for 84% of all greenhouse gas emissions. Heating the building takes the largest share of energy but whoever is the lowest production of carbon. This position is reserved for cooling which account for 13% (Roodman, & Lenssen, 1995). A focus on commercial buildings reveals that buildings are used for a number of purposes including commercial, office, recreation and communication. Office buildings are the single largest contributor to the carbon emissions of the building and it is in this section that considerable efforts need to be put (United Nation Environmental Program, 2009). In order to make a substantial impact and reduce the production of carbon building for his purpose need to be built in a more environmentally friendly manner. The focus of the regulating programs is to reduce the energy consumption of the building and the effect is the reduction of carbon emission.
According to Bansal, & Roth (2000), carbon emissions from buildings has been a major source of concern because of increased estimates of energy consumption and carbon emissions by various types of buildings. Reports on this matter have led to increased knowledge of emission of Green House Gases from buildings in the quest to come up with better levels of building sustainability. Pout et al. (2002) mentioned that in year 2000, CO2 emissions from the use of energy in commercial buildings accounted for a quarter of all UK emissions. This emission included industrial energy use by public sector and commercial buildings. Lighting accounts for a quarter of these emissions (Olgyay, & Seruto, 2010). Space cooling translates to about 5% of commercial and public emissions. Nevertheless, in buildings where there is installation of air conditioning, cooling can account for a large portion of carbon emissions and the use of air conditioning has increased in the recent past (Barnea, Heinkel, & Kraus, 2005).
Abatement curves for cost indicate contributions made at national levels with an option that is efficient in terms of energy. Moreover, saving cost to be realized after implementation is also indicated. This form of assessment reveals technical potential of saving carbon in commercial and public buildings across a number of countries. Concisely, this technical potential lies at around 35% although 20% more can be achieved devoid of cost increments. According to UN AGECC (2010), there was a decrease of carbon emissions by 45% during the period between 2000 and 2010. Analogously, there was a 14% increase in consumption of energy.
Research on International Green Building Rating Systems: USA, UK, UAE
The Green Star rating system for building was formulated by the GBCA, the building council in Australia. This rating system is comprehensive in evaluating the environmental performance and design of Australia buildings based on a variety of categories. The categories in the tools for Green Star rating are; management, energy, transport, indoor environmental quality, water, materials, ecology and land use, and emissions (Pout, MacKenzie, & Bettle, 2002)
The rating tool in UAE includes a number of systems for rating building sustainability in the global marketplace. Estidama Pearl Rating is a rating system is primarily adopted in assessing building sustainability in the UAE. The UAE has also adopted the use of other building sustainability Rating Systems such as LEED developed in the United States, and BREAM, established in the United Kingdom (Lee, & Burnett, 2007).
The Estidama rating tool is split into seven categories, vital for sustainable development. These categories include a development process that is integrated. Such a development process aims at encouraging teamwork across all disciplines with the aim of delivering solutions that are environmentally sustainable for the established environment. In addition, the Estidama rating tools incorporate natural systems that conserve restore, and preserve, critical habitats and natural environments (Kibert, 2003). Third, Precious Water is a concept that caters for reduction of water demand while supporting usage of substitute water sources. The concept of Liveable Buildings in the Estidama Rating tool ensures that there are quality indoor and outdoor spaces. Further, there exists the Resourceful energy concept that promotes the conservation of energy via measures of passive design, renewable and energy efficiency (Dixon, Colantonio, Shiers, Reed, Wilkinson, & Gallimore, 2008). Stewarding Materials in the Estidama rating tool is important in catering for the reduction of the impact of extraction of building materials. It also caters for the manufacture, transportation and the disposal of building materials. Through Innovative Practice, the Estidama rating tool encourages cultural expression and innovation in design building and construction in order to facilitate industrial and market transformation (Fowler, & Rauch, 2006).
Methodology
Standard: Green Star, LEED and BREEAM
To arrive at better a better Green Star rating approach, this study will employ the use case studies that have undergone ratings from the three leading agencies. The benchmark analysis between the principal rating tools: LEED, BREEAM and Green Star will lead to unlocking of the loopholes in Green Star. The study will incorporate the use of 4 case studies to help identify the categories and weightings where Green Star rating is falling behind in regards to the other two mentioned schemes.
The study will also look at the structure of ratings at Green Star with a critical view where weaknesses will be indentified. The researcher will use expert opinions to come up with solutions to these weaknesses. The analysis will help in improving the rating agencys performance in the market. For example, currently, the materials category under Green Star is based on specific environmental criteria that encourage the use of recycled and re-used objects. Green star additionally concentrate too much on a vast range of material used in the building sector, such as timber, steel, PVC and concrete. However, Green Star is deficient in not requiring a Life Cycle Assessment (LCA) to measure the environmental performance of such materials.
Analyzing Case studies and Discussions
Case Studies
The case studies below will invariably highlight the fundamental differences that will inform future improvements of Green Star in an effort to play catch with world leaders LEED and BREEAM. While the researcher realizes the inconclusive nature of case studies, they bring about the specificity of application of rating systems while denigrating (though to a certain extent) generic applications of the rating systems. The case studies will be analysed on a case-by-case basis drawing conclusions from all the three major rating systems with regard to improvement insights of Green Star.
Case Study 1: Pixel Building
Pixels project objective was to design and construct the worlds first carbon neutral and water balanced office building with regard to both operational and carbon emissions (Sustainability Victoria, 2012). Pixel was the first building in the world to undergo certification in all the three leading rating systems: Green Star, LEED, and BREEAM. Pixel building is a perfect example on how an ideal score in Green Star may not be reflected in BREEAM and LEED. The magnificently sustainable infrastructure was built in Melbourne with the ambitious goal to score every point in the three Green Rating Systems. In Green Star, the building scored a perfect 105, but in so far it has only scored a 99.4% out of 110% in BREAM and 103 out of 110 in LEED. The main difference in the score of Pixel building is that Green Star favours the score of infrastructure within Australia. More importantly, many of the things they did to earn credits are not very good solutions at all, so it definitely revealed many flaws with Green Star. Therefore, Pixel Building paints a picture of a need for improving Green Star. On the other hand, does it need improving? It is crucial to note the specific nature of Green Star concerning an Australian setting hence the perfect score.
Analysis/Discussions
In terms of sustainable materials intended to minimise carbon emissions, the strategies included:
Using the Pixelcrete concrete, which has been shown to halve the embodied carbon of the mix when compared with traditional 40 MPA concrete mix designs. The pixelcrete concrete is used as a substitute for the normal concrete mix-design as it contains less impact on environment containing 60% less cement and achieves the same strength as the traditional concrete.
Using unique external shading material to minimise solar thermal loads by cutting or bouncing off harmful emissions that eat away the ozone layer,
That ensures minimal carbon emission from gas usage in the building for heating purpose. Additionally, using a gas fired absorption chiller that employs ammonia refrigerant, as it has no ozone depleting potential or any possibility of legionella. This is different than the traditional chlorofluorocarbon (CFC) which has a negative impact on ozone layer and upper atmosphere, and
Designing renewable energy systems into the building, consisting of fixed and tracking photovoltaic and wind turbines on the roof, in addition to a small amount of biogas produced from an anaerobic digester connected to the vacuum toilet black water system (Sustainability Victoria, 2012).
The above areas mostly fall under Green Star Energy, Emissions, and Materials categories. Green Star has 9 distinct categories. Whereas all categories earn individual credits, which are in turn used as a weighing factor in arriving at the final score, Pixel Buildings score does not reflect that. It is not logical to ascertain the manner in which Pixel Building earned a perfect score of 105 (i.e. a world leader in sustainability). Hence, it would be easier to view other Rating Systems that did not award perfect scores more favourably than Green Star. Green Star used office V3 rating tool, which does not recognize such aspects of sustainability such as solar usage, which further dents the perfect score. Pixel is an example of how a perfect score in Green Star may not be reflected in BREEAM and LEED. Pixel is an infrastructure that was built in Melbourne with the ambitious goal to score every point in the green rating systems. In Green Star this building score a perfect 105, but under BREEAM has only scored a 99.4% out of 110% and in LEED 103 out of 110 points.
Case Study 2: VS1
The building has also obtained accreditation in the three rating systems Green Star, LEED and BREEAM. Sprawled on a 35 thousand square meter, VS1 is a new office building that is based in Adelaide. The local conditions in Adelaide afford this building high efficiency in usage of water and energy.
The VS1 building in Victoria Square has a strong focus on water conservation and energy reduction and is expected to achieve a reduction of approximately 70% in portable mains water consumption, and a reduction of approximately 50% in green gas emissions and energy costs compared to a typical office building (Green Building Council of Australia).
Figure 2: VS1 Building -Points achieved (based on 100 total) highlights the score obtained by this building in the three major building rating tools. In this case, VS1 has obtained a higher score in Green Star than in other two rating schemes. LEED rating system has been particularly hard on VS1 mainly because of the difficulty to get score in the construction materials category and because LEED regards highly the use of renewable green energy. The BREEAM score does not vary as much with Green Star though it higher in the ecology criterion.
Analysis/Discussions
In terms of sustainable strategies intended to minimise carbon emissions, the strategies included:
Using low Volatile Organic Component (VOC) off-gassing carpets, paints, sealants and adhesives. While VOC is included in many materials of construction, using Low VOC building material and furnishing can reduce the emission of smog-forming in a very dramatically way. It can also minimise the occurrence of irritations that related to humans such as headache and eye irritations (Reed, Bilos, Wilkinson & Schulte, 2009).
Using low formaldehyde off-gassing joinery,
Monitored recycling of over 90% of construction and demolition waste,
Using non-poly vinyl chloride (PVC) piping, conduits, sub-mains, flooring and blinds. The PVC is a third most common used plastic due to its effectiveness in construction and building materials. However the density of plastic that PVC has is higher than any other plastic, therefore it was not used in this building as it leads to higher carbon emissions a measure that reduces a rating score,
Replacing 20% of Portland cement in concrete with fly ash. Portland cement is high carbons contain products which omits carbon during the hydration process when used in concrete or mortar. On the other hand if fly ash, which is a waste material, generated after coal-burning process is used it reduces the amount of carbon during the hydration process as International Energy Agency (2012) finds.
Using a highly specified and sensitive western veil in front of the building skin to minimise solar loads. This veil controls the amount of sunlight that enters the building can be adjusted according to the human requirements.
Using ETFE roof over full height central atrium to facilitate natural light into the heart of the building. ETFE is a polymer and its source-based name is poly (ethene-co-tetrafluoroethene), and its film is self-cleaning (due to its non-stick surface) and recyclable.
Using exhaust riser for printer and photocopy rooms that improves the indoor air quality. This is part of a wider solution to tackling carbon emissions and their effect,
Employing humidity sensors in supply air ducts to control humidity and minimise potential for mould growth that are detrimental to lifelong durability. Durability is a factor in suitability as it caters to resource usage optimization (Green Building Council Australian, 2013).
Figure 2: VS1 Building -Points achieved (based on 100 totals) Source: Green Building Council Australia
The above points reflect that Green Star may have exhausted all categories in arriving at the score. Most notably was Energy (ETFE and Water Energy) and Materials (cement, PVC, veil). The six star score however, is above the two other ratings LEED and BREEAM because Green Star is somewhat favourable. For future growth, Green Star should come up with stricter rating tools such Multi Unit Residential V1. In this regard, this work states that the main two main desired features to be improved in Green Star rating are in the materials and Green House Gas (GHG) emissions/pollution categories. This way sustainability will reach new heights.
VS1 achieved a higher score in Green Star than in the other two rating schemes. LEED rating system has been particularly hard on VS1 mainly because of the difficulty to get score in the construction materials category and because LEED regards highly the use of renewable green energy.
Case Study 3: 55 St Andrews Place
The 55 St Andrews Place is a refurbished building in Melbourne CBD with a construction area of 6 thousand square meters and granted the BSJ award for sustainable refurbishment of the year 2007. The building intended to merely achieve high levels of sustainable design be it from whichever rating system. This building has also taken certification from Green Star, BREEAM and LEED. Figure 3: 55 St Andrews Place Building -Points achieved (based on 100 total) presents the findings of the rating agencies. In this case, the highest score for this building was achieved under BREEAM, this is mainly because this rating scheme rewards improving existing building infrastructure more than LEED and Green Star and because it gives more points for energy improvement. However, the intention for suitability is achieved.
In terms of sustainable materials intended to minimise carbon emissions, the strategies used by the project designers and developers included:
Replacing punched window glazing with clear glass to enhance daylight potential, improve comfort and reduce air conditioning needs.
Installing external automated blinds to control solar load before it enters the building.
Replacing the large expanse of full height tinted glazing in the office area with an insulated 1.2m high spandrel panel and new low-e glass to improve comfort and increased daylight levels.
Reducing construction waste by reusing as many materials as possible.
Avoiding PVC and other materials that are known to have substantial off gassing (Clark, 2009).
Figure 3: 55 St Andres Place (Refurbished) -Points achieved (based on 100 totals), Source Green Building Council Australia
In the above case, Green star performs better at rating. It was the first rating that Green Star carried out without TCs and CRIs getting involved. The procedural hurdle that crops up when different ratings are arrived at from similar submissions was eliminated. Similar approach should be employed in future. In similar breadth, it is notable to see that LEED and BREEAM gave higher ratings than Green Star on this one. The 55 St Andrews Place achieved a higher score under BREEAM than in the other two rating schemes. This result is mainly explained because BREEAM rating scheme rewards improving existing building infrastructure more than LEED and Green Star and because it gives more points for energy improvement.
Case Study 4: The Cundall Office
The 400 square meter fit-out project Cundall office, based in Sydney has had the certification of LEED, BREEAM and Green Star. The results can be better appreciated in Figure 4: The Cundall Sydney office (fit-out) Points achieved (based on a 100 total). It is crucial to note that discrepancies in the scores. The reason is that in this particular case the methodology of the rating tool systems varies significantly due to the nature of the project (i.e. fit out). Hence, the rating agencies carry out the building assessment is done in an entirely different manner. Furthermore, the assessment changes significantly for fit-out furniture. While Green star appraises furniture piece by piece, LEED adds up all the furniture together and BREEAM does not evaluate. This explicably leads to discrepancy. One factor that also explains the considerable disparity in rating building scores is that BREEAM and Green Star are mainly focused on tenancies with formal contracts. LEED does not put too much emphasis on that factor. However, these discrepancies inform the reader of the specific nature of each rating agency.
Figure 4: Cundall Sydney office (Refurbished) -Points achieved (based on 100 totals), Source Green Building Council Australia
This was a poor score from Green Star. One of the main issues under Green Star that needs to be corrected for achieving a more sustainable building stock in Australia is the fact that most Green Star accreditation occurs under the design stage. This accreditation has the potential effect to tempt developers to execute the project in an entirely different manner. To deal with this issue, Green Star has a number of As-Built ratings, which are not necessarily attached to obtaining an overall Green Star rating. The above case highlights this well. It is the main reason that the project received a lower rating.
The Cundall Sydney office achieved a higher score under LEED rating system. In this particular case, the nature of the building project (i.e. fit out), results in the building score been granted in an entirely different manner. The reason is that case studies vary in the nature of the property project (i.e. new construction, refurbished, fit out) without a doubt the nature of the project plays a significant role in the score granted by the LEED, BREEAM and Green Star rating systems. Therefore, domestic and industrial construction development face different methodologies for green accreditation and this creates further difficulties for comparison purposes around international rating tools.
Assumption Testing and Results
The overall environmental approach by Green Star rating system is not is as strong as LEED and BREEAM in regards to the assessment of design, actual and performance of sustainable building in Australia. The Australian building projects that have obtained accreditation in LEED, BREEAM and Green Star ratings arrives at the following tests for results.
Assumption 1 validated by the following tests and results:
Benchmark analysis between LEED, BREEAM and Green Star tool Rating Systems.
The case study analyses above reveal notable discrepancies between Green Star, LEED, and BREEAM in awarding rating scores. The discrepancy are in favour of the client when Green Star rates. The results indicate that Green Star categories and credit point allocations somehow collide.
BREEAM building management credentials are top notch compared to the other rating systems LEED and Green Star.
Green Star falls behind in the category of Green House Gas (GHG) emission and pollution category. Therefore, Green Star rating is inefficient in measuring and controlling Green House Gas (GHG) emissions and pollution levels in the building stock.
Different approaches in credit point allocations between LEED and Green star are apparent. LEED approach concentrates on Design and construction stages. A review of the initiatives at the design stage may lead to award of certification from LEED although this waits until construction is complete. However, accreditation does not happen after construction in Green Star it happens at the design stage. This loophole allows clients to obtain accreditation and execute differently which dents Green Stars credibility.
Currently, the materials category under Green Star is based on specific environmental criteria that encourage the use of recycled and re-used objects. However, Green Star is deficient in not requiring a Life Cycle Assessment (LCA) to measure the environmental performance of such materials. LCA evaluation is currently included by BREEAM in the category of construction materials but not yet by LEED.
The cases were good examples of sustainable buildings that are regarded as Ideal buildings for the near future or for next generations. The new designs and strategies implementations under the environmental impacts and LCA are commendable.
The buildings under the case studies did not minimise the emissions 100%. On the other hand, they created examples or benchmarks capable of emulation in future construction.
Weaknesses of Green Star
Green Star building rating system has a few weaknesses in comparison to other progressive rating systems such as LEED (Leadership in Energy and Environmental Design) and BREEAM (Building Research Establishment Environmental Assessment) from the United States and United Kingdom Green Building Councils. One of the greatest setbacks of Green Star is arrival at differing results when similar projects make similar submissions for certification (Green Building Council of Australia 2013). This inconsistency dents its credibility and further enhances the fact that it cannot be standardized even in a smaller environment, which may disgruntle clientele. Second, Green Star certification takes too long with high costs and complex third party consultation structures. Third, the points attained tend to be criticized for not realizing some critical aspects (Green Building Council of Australia 2013). For example, roof solar energy is not included in the credit point for Green Star. This has contributed partly to the lower performance rating of less than 80% in 2012 (Green Building Council of Australia 2013). Others like LEED and BREEAM enjoyed better performance ratings. The fees associated with Green Star are too broad and somewhat complicating to the client. They include consulting fees and Green Star Certification fee. Clients do not enjoy consulting fees since they are too disjointed (fees for documentation requirements, inconsistent assessment fees among others) (Green Building Council of Australia 2013). The fourth weakness is that Green Star rating system does not take into account residential buildings such as town houses. The system is specifically designed for commercial houses (Dirlich, 2011). Lastly, Green Stars data collection for credit allocations is not reliable due to the model, which calculates the carbon emission. The model is incapable of determining inbuilt stochasticity of infrastructure emissions and the existence of unobserved explanatory variables is neglected (Green Building Council of Australia 2013). This leads undesired discrepancies in ratings for similar submissions (Green Building Council of Australia 2013).
Green Star uses LCA to measure performance of materials. However, the importance in the implementation of a LCA lies on the fact that construction materials have a significant environmental impact that extend beyond the building itself. In other words, most of the buildings environmental impacts are derived from the materials that are used in construction. Furthermore, according to the 2030 Challenge for Products it is estimated that the environmental impact (i.e. measured by Gas (GHG) emissions and energy usage) from the materials required in constructing buildings will only be equalled after a period of twenty to thirty years of building operations. In addition, the difference between environmental impact of construction materials and building operations will only extend further if the scope of the analysis were to consider the full collateral effects that are involved along the multiple production steps required in the life cycle of construction materials: extraction of raw materials, manufacturing, transportation, use and final disposal. In this regard, one more reason that justifies the execution of a LCA is the need for a coherent Green Star rating system that includes a better measurement in the material category and, therefore, favours the use of environmentally friendly construction materials in the building sector. This will create an incentive for demand and innovation in the use of more sustainable materials across the building industry. A good example of these products can be found in sustainably produced wood and green cleaning products.
Moreover, a LCA on construction materials would generate a comprehensive analysis that includes the life cycle of a product and, in doing so, facilitates knowledgeable decisions that will consequently deliver higher benefits for local communities, the environment and human health. The implications of including a LCA analysis on the Green Star rating have the potential to transform and expand new directions in sustainable building across Australia.
In regards to the Green House Gas (GHG) emission and pollution category Green Star is considerably far behind BREEAM and LEED schemes. This is mainly because Green Stars attributes are more design-oriented rather than being a rating tool to be applied for actual performance on sustainable building operations. Therefore, Green Star rating is inefficient in measuring and controlling Green House Gas (GHG) emissions and pollution levels in the building stock. This sustainability issue is addressed in different ways by BREEAM and LEED rating systems: the first scheme directly encourages the reduction in carbon emissions to zero net emissions by granting in this category up to 10.56 % of its overall score; whereas the latter is more focused in indoor air pollutants reduction, especially those that are detrimental, scented or irritant to the well-being of occupants. The actual performance sustainability gap in the Australian construction industry is filled by NABERS, which is a national and mandatory rating tool which role is to evaluate performance in terms of energy efficiency and carbon emissions. Consequently, the green building industry in Australia has a high level of dependence in the federal government to establish adequate levels of sustainable performance, through measures that include the Commercial Building Disclosure scheme and Tax Breaks for Green Buildings
Solutions for Green Star Weaknesses
The above shortcomings allow Green Star competitors to have an upper hand in ratings. In its 2012 report, Green Star undertakes to improve its rating to include residential houses (Green Building Council of Australia 2013). Noting that new residential buildings account for over 60% of the total upcoming buildings, Green Star undertakes to rate them too (Green Building Council of Australia 2013). Additionally, green Star should make more changes in point allocations. For example, buildings with solar panels should enjoy better ratings as this sustainable use of energy cuts carbon emissions by 30% according to Portalatin, Koepe, Rostoski & Shouse (2010). Residential construction material (a factor that Green Star uses) is much more sustainable too as opposed to commercial buildings. Technical clarifications (TCs and Credit Interpretation Requests (CIRs) should be enhanced to allow the Rating Agencys products such Retail, Multi Unit Residential, Healthcare, and the new Design and Build be less expensive (Green Building Council of Australia 2013). To attain better credits it is also incumbent upon Green Star to come up with a list of accredited suppliers and products for multiple projects for better ratings. This will reduce confusion associated with the need for a good rating but no specific of attaining one (Dirlich, 2011). Queries associated with the certification process should be enhanced too. This will ease communication flow from GBCA, TCs, CIRs and clients that hasten delivery of services. It is also incumbent upon Green Star to enhance consistency of assessments. Assessors ought to be accessible and TCs, CIRs should be followed up (Green Building Council of Australia 2013). This will eliminate any mischief in assessment and will enhance efficiency and effectiveness. In light of the above weaknesses, the preceding solutions may project Green Star in a better position with its competitors. It will go a long way in improving t he rating system to reflect the objectives of sustainability (Dirlich, 2011). A further look at credit points allocation should be done with the aim of a review to factor in residential buildings. Some sustainable features such solar water heating systems, solar lighting, use renewable gas for cooking, use of rain water preservation points among others are quite common in residential buildings (Green Building Council of Australia 2013).Third party consultants make the whole process of rating expensive especially when similar submissions arrive at different ratings (Green Building Council of Australia 2013). Green Star rating should overhaul data collection methods by catering for unexplained variables. These way similar submissions will arrive at similar results which effectively expensive processes of hiring TCs and CRIs (Green Building Council of Australia 2013). LEED and BREEAM also reach a higher standard than Green Star in terms of energy efficiency. LEED and BREEAM rating tools take into multiple environmental criteria for assessing performance based on two building references. On the contrary, Green Star scheme predicts performance based on only one building reference and considering less diverse environmental criteria to be included in the evaluation; consequently, any modifications can have a significant effect on the outcome of the energy score.
Future Trends
Future advancements in rating for sustainability may involve the following group of initiatives that will help to expand the awareness and positive response towards sustainability.
Obtain more case studies with diverse and sophisticated needs for rating where LEED, BREEAM and Green Star are applied in an international context. More useful data banks and information centres will be generated that will lead to a better understanding of building ratings.
The World Green Building Council could rally all national and regional rating tools in coming up with a global rating scheme. The scheme should have standardized environmental measurement and comparison tools. WBC would play a supervisory as role the National Agency plays the role of implementer.
Green Star could look upon the future trends of LEED and BREEM schemes for analysis and comparison. Nuggets of information obtained could be instrumental to Green Building Council of Australia (GBCA) in understanding growth in this area and positioning Green Star and other agencies towards obtaining lofty statuses of agencies such LEED and BREEAM.
Conclusions
Green building accreditations given to a project by a single rating scheme (e.g. LEED) reflects just a portion of accuracy the sustainability grade (e.g. six stars) of a building. This is proven by the fact that the score granted by LEED, BREEAM and Green Star rating systems could vary significantly under the same building. Could this be a pointer towards weaker rating tools? The paper arrives at some weak areas associated with Green Star.
The results based on the case studies show that green accreditation levels under LEED, BREEAM and Green Star will vary according to the nature of the property project (i.e. new construction, refurbished, fit out).
More transparency between rating tools will benefit the development of sustainable infrastructure. Since this will increase property value and market competition, and consequently, generate a more pro-active building industry towards the achievement of sustainable accreditation.
The development of a global rating scheme that is straightforward in terms of environmental measurement and international comparison purposes will undoubtedly deliver multiple benefits to the infrastructure industry. However, the main trade-off in doing this is that customized rating schemes are more successful in measuring environmental performance according to the particular needs of a determined country, state, or territory.
The economy outlook is an important factor to take into account when it comes to establishing environmental rating policies for the building industry. More specifically, an economic crisis will discourage the infrastructure development market to go through green building accreditation that demands stricter environmental standards.
Weaknesses such as structural expensive nature of TCs and CRIs paint a bad picture of Green Star. The rating system also is less diverse in its conclusions. The fact that they give accreditation at the design stage creates a situation where it may be manipulated.
As part of solutions, Green Star needs to reevaluate its structures to eliminate these loopholes, reduce expensive red tape, and communicate more to clients and rate buildings based on trends to be a world-beater.
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There is no doubt, whatsoever, that London is home to some of the most fascinating structures around the world. However, Norman Fosters 30 St Mary Axe, generally referred to as the Gherkin or Swiss Re Building, inspired by the design of aircraft and their interaction with the wind, is a mesmerizing piece of work. Located in Londons central business district, the building opened its doors on April 28, 2004 (Arch Daily par. 1). It was greeted with outpouring comments regarding its appearance. The architecture of this mega structure is not only aesthetic but also critical to energy efficiency in this era of major environmental and energy concerns. The diagrid structure, the double-shell ventilation system and the rotation of floors to incorporate vertical light wells make the building a unique study case.
Material Considerations
Critical considerations were made by the constructors on the nature of the materials used to realize the Icon. For instance, one of the major considerations made was the use of a diagonal steel structure (diagrid) to achieve the curved, tapering structure. The design of the structure made the use of intertwining materials in order to improve its stability and strength. Strong pieces of steel metal provide it with strength from the ground. It is amazing that the iconic structure is made of about fifty-five kilometers of strong metallic components, which weigh about ten thousand tonnes. Where possible, the tower utilized both recycled and recyclable materials in the construction for both environmental conservation purposes and to lower costs (Arch Daily par. 5).
Design Details
In order to achieve the desired structure, the designers of the building utilized modeling techniques, which were based on aerospace and automobile principles. The mathematical principles employed in the modeling approaches ensured that the structure acquired a stable 3-D appearance. Due to the adoption of the 3-D modeling platform, a change in any of the elements could result in a change in the other elements of the building. As such, the entire structure is able to retain its overall complex form. Since the site was small, the tapering design gives room for construction and reduced the chances of space wastage by the regular rectangular blocks. The design also is slim at the base to reduce reflections and improve the overall lighting of the building. The shape of the structure was designed to prevent the wind from negatively affecting the building. This also helped the engineers because they did not need to look for more reinforcements.
Figure 1. An architectural plan of the Gherkin. Adapted from Arch Daily. The Gherkin. n.d. Web.
Relationship to Context
Located at the heart of Londons central business district is the Gherkin. Looming at the height of 150 meters, the structure is an amazing spectacle to thousands of people who see it. Architecture seeks to enrich the lives of the people. This is what the Gherkin does all the time. Being home to some of the best restaurants in London, it offers clients beautiful scenes. In fact, the Gherkin is indeed one of the major steps forward for architecture around the world.
Projections
It is a personal submission that the Gherkin was an icon in the history of architecture. I, therefore, feel that the clients brief was fully met in the undertaking. In addition, the numerous international accolades the structure has won are more than enough evidence that the building was an icon in quarters that appreciate the value of creative architectural minds.
The city of London has many skyscrapers that stand tall in all streets. They depict Londons rich history of development and evolution of the building culture. However, a discussion of the history of the city of London is incomplete without considering Saint Pauls Cathedral. The cathedral forms one of the glamorous and famous icons of London.
Its dome that has some framed spires has been a unique skyline feature in the architectural work for over 300 years. Standing at 111.3m, the cathedral was the tallest structure between 1710 and 1962. However, until today, its dome is one of the highest across the world. From the context of area coverage, it takes the second position for all churches in the UK after the Liverpool Cathedral (Campbell 34).
The cathedral constitutes a centerpiece for the English peoples identity. Campbell supports this assertion by adding that many promotional materials deploy it as their main subject, especially its long-standing dome that is surrounded by Blitz fire and smoke (71). The church building has housed important ceremonies, including Sir Churchill and Lord Nelsons burial services, Peace services to mark the end of 1st and 2nd World Wars, and wedding services for prominent person such as Sir Charles, the Prince of Wales.
The church has also been used as the venue for marking important times in the English history such as Diamond Jubilee, Golden Jubilee, and 80th Birthday (Campbell 83). The structure is an all-time busy building that holds services and prayer sessions on a daily basis. Hence, it is clear that even with modern design solutions, the work of Wren remains an important reflection of the glamour of London and the United Kingdom.
Location of the Building
Saint Pauls Cathedral functions as the heart of the Anglican Diocese of London. It is located at Ludgate Hill, which is the highest site in London city. Sir Christopher Wren had the honor of designing it in the 17th century. The building process was completed when Wren was still energetic. It was part of a rebuilding program that followed the occurrence of the Greatest Fire of London (Tatton-Brown and Crook 103), which destroyed the predecessor building.
The current Saint Pauls Cathedral in London was built between 1675 and 1710. The church was the first cathedral to be built after the English Reformation in the sixteenth-century, when Henry VIII removed the Church of England from the jurisdiction of the Pope when the Crown took control of the life of the church (Tatton-Brown and Crook 19). Wren had begun offering advice on the renovation of the old Saint Pauls Cathedral in1661.
However, the fire of the Great Britain destroyed it in 1666, thus prompting the need for developing a new design after its demolition in 1670. William Sancroft laid down the anticipated architectural design outcome in 1668. He wrote to Wren informing him that in consensus between Londons bishops and Canterbury Archbishop, he was charged with the responsibility of designing and overseeing construction of a handsome church, which also retained the reputation and glamour of the nation and city of London (Campbell 36).
Designing Saint Pauls Cathedral took several years. The agreed upon design was attached to the royal warrant. However, provisions were made to permit Wren to make necessary alterations, which he deemed appropriate. The repercussion of the changes was the current cathedral that has one of the most appealing domes across the world. Coal tax was deployed as the main source of finance to build the cathedral. Although the construction process ended on 26 October in 1709, the upper house declared the conclusion of the church on December 1711. However, the construction went on for a number of years. Indeed, statues that are seen on the roof were placed in 1720s. By 1716, the building had used about 1,095,556 sterling pounds, an equivalent of 143 million sterling pounds in 2014.
Culture and Society
The design of city buildings and structures reflects knowledge base and values of the society. This observation suggests that buildings have cultural purposes since they reflect the cultural progression of a society. Hence, the design and construction of Saint Pauls Cathedral was to be accomplished in a manner that reflected the status of the city of London. This plan implied that the cathedral needed to reflect and/or symbolize the status of the society in which it was erected.
The impacts of the architectural creation of Wren were reflective of the material culture and building technology during its time of construction, but with added innovation and creativity in terms of assembly of materials and appearance of the fully developed architectural work. The fact that Wren was dedicated to design a structure that reflected the caliber of the nation and city suggests the existence of a cultural mentality and belief in excessive and competitive consumption.
Wren was involved in advising on renovation of the old cathedral before the great London fire destroyed it. This situation meant that during the design processes of a new cathedral, he was to ensure that he developed a unique structure in the extent that it could not look like any other cathedral that had been developed on the same site before. Such a motif reflected the culture of competition in developing new skyscrapers. Since the building would be used as an iconic center for many functions of the Anglican Church in London, the design and construction process needed to reflect the English culture of owning the best and the most attractive worship center. Indeed, a look at the cathedral picture in figure 1 evidences Wrens success in delivering this cultural anticipation.
Fig. 1: Saint Pauls Cathedral. Source: (Blundy par.1).
Many design aspects of Saint Pauls Cathedral reflect the building culture for worship centers across the globe at its time of construction. When Wren was given the authority to make changes on the design during the construction process, he took an immense advantage of it. One of the major changes was done on the dome. Wren raised an additional mega feature over the original cupola or the brick cone. This change was done in a bid to support a stone-made light, which formed an elegant feature.
He also covered a brick-made cone with wood and lead cupola (Campbell 59). These features were borrowed from the design of St Peters Basilica that is located in Rome, Italy. The culture of designs for worship centers is also reflected in the Saucer Domes that are located at Nave. The original idea in its design was borrowed from the Val-de-Grace church, which forms part of Francois work, which Saint Pauls Cathedral designer saw when he visited Paris in 1665 (Sankey 78).
The design of Saint Pauls Cathedral was highly influenced by the Baroque styles. This resemblance depicted the capacity of its designer to rationalize various building cultural traditions in the English world and other places such as the work of Polladio and Mansart (Tatton-Brown and Crook 89). Medieval influences are evident on the transepts of the church.
Construction of the Building
The main challenge in the construction process was building a large building on a weak ground (clay soil). The building also has one of the largest crypts across the world. Although it is huge enough, piers occupy most of its (crypt) space. They (piers) absorb the weight of smaller piers (Tatton-Brown and Crook 90). In the construction of other cathedrals across the world, four main piers support most of the weights. However, Wrens building has incorporated eight piers. This plan has the effect of enhancing better weight distribution in the foundation. During the construction process, changes occurred on the building ground akin to its relative weakness, although Wren responded by making the appropriate structural alterations.
The critical challenge that Wren faced in the design process and subsequently in the construction process was making not only visually satisfying architectural work, but also replacing the lost cultural significance of the old St Pauls Cathedral following the occurrence of the London fire in1666. Wren had to address the problem of visual impression since it constituted one of the most important anticipated building characteristics.
One of smart ways of accomplishing this mission was to divide and extend the external and interior heights for the churchs pitch above the level that had been reached by the designer of St Peters Cathedral through utilization of curves. To achieve this goal, he inserted a brick- made cone, which supported the outer domes, which were covered with lead. Stone lantern was made to rise at great heights above it as shown on figure 2.
Fig. 2: Cone Supporting the Inner and Outer Domes and the Lantern. Source: (Tatton-Brown and Crook 147).
The inner dome and the cone have a thickness of 18 inches. They are supported using iron shackles. The design has some buttresses that are placed superficially at the ground floor. Before the commencement of the construction, Wren altered the elements, which did not comprise a classical aspect of the design. Instead, he constructed a thick wall to eliminate the buttresses. However, flying buttresses were deployed in the reinforcement of clerestory and the vault. This feature was only incorporated in much late stages of the design with the aim of providing extra strength.
Materials
Without materials, Wrens design would not have been physically actualized. The main building material for the cathedral was Portland stone. Indeed, the church was one of the very first buildings to deploy this kind of stone. Large quantities of it were required in the construction, which made King Charles II issue special orders that no Portland stone would be mined for any other purpose without Wrens consent (Tatton-Brown and Crook 161). Other major materials were lead, timber, marble, and wrought iron. Stone and timber formed the subject on which the engraving and sculpture works were done. Wrought iron was mainly deployed in fencing, although it was not Wrens deliberate choice. He had preferred hammered iron since it could be made more decorative compared to wrought iron.
Exterior Design
The most outstanding feature from outer side of the cathedral is the dome. It rises about 111 meters, thus making it the dominant mark of the Londons sky space. Unlike the domes of the Val-de-Grace and the St Peters Cathedral in Rome, Wrens dome rises in two-story masonry. Looking at the building from a distance, one clearly sees the columned porch. This design element anchors the interior pitch and the conduits. The conduit provides the necessary support for the long-standing illumination.
On top of the columned porch, Wren positioned a stone gallery, which is elegantly decorated. The dome, which is covered by lead, rises above the columned porch below the lantern. Eight luminous gadgets penetrate, although they are not clearly visible. West front transepts have a half-circle portico in the entrance. Windows are located between pilasters. The underside openings possess patterns that take after the Roman artistic work. Gibbons stone carvings appear beneath the windows. The pulpit rises 110 feet above the ground level.
Interior Design
From inside of the cathedral, one clearly sees the central part of the building that is meant to accommodate bands of singers. A domed narthex that takes the shape of a square forms the entrance of the cathedral from the west portico. St George, St Dustan, and St Michael chapels are flaked on its either side. The central part that is designed to house bands is raised 28m high. Passageways have been designed using special structures (cloisters berths). The cathedral has a section, which provides anchorage to the churchs organs and pulpit team among others. The interior view of the dome represents a particularity impressive artistic creation of the 17th century as shown in figure 3 below. Along the width of the choir is the apse that has mosaic decorations.
Fig. 3: Interior View of the Dome. Source: (Tatton-Brown and Crook 148).
Labor Force
Throughout the design process, Wren worked with Nicholas Hawksmoor as a personal helper while Dickinson functioned as a measuring clerk. Marshall, Edward, and Strong were employed as chief masons. After the demise of Marshall in 1678, the two brothers worked to the finishing point of the cathedral. Langland operated as a chief carpenter all through the construction process. Grinling operated as a chief sculptor.
He took active roles in the North Portal construction in addition to supervising internal wooden fittings. However, Caius Gabriel sculptured the southern pediment transept (Tatton-Brown and Crook 113). Francis Bird was engaged in making the relief on west pediment and various other statues that appeared on the west front of the cathedral. In 1709, William Dickson took up the responsibility of laying concrete on the cathedral base with sandstone. This task was accomplished in 1710. However, there lacks evidence on the exact number of people who were employed to complete the project.
If it were Today
Peoples artistic creativity develops as time progresses. This claim is perhaps true with reference to the construction of St Pauls Cathedral. If the construction could be done today, tools that were used in the construction would also be different. The construction would probably involve a heavy use of equipment and different materials, rather than just stones, lead, iron, and timber. For example, instead of stones and wooden fittings that formed part of the structural components that provided strength in the building, pre-stressed concrete would most be appropriate to minimize time that would be required to complete the construction from over 30 years to about five or three years. Pre-stressing is one of the methodologies that are deployed by modern structural engineers to mitigate natural drawbacks of steel concrete structures.
The methodology is employed to produce various commercial structures. Pre-stressing is done on floors, bridges, and beams. Concrete withstands more loads while subjected to compressive loads than while subjected to tensile loads. This behaviour implies that it can withstand more loads when used to produce columns that are to be subjected to compressive loads relative to when it supports loads that subject it to tension.
A similar scenario is experienced when concrete is deployed to produce a beam. For instance, when a beam is simply supported and loaded, the dead load (load due to the weight of the beam) and the applied load subject the upper portion of the beam to compressive deformation. The lower side is subjected to tensile strain, which induces tensile stress. Since non-reinforced concrete is stronger in compression than in tension, the beam can only support a limited amount of load in tension.
When the span of a beam is increased, the supportable load reduces because longer spans buckle more than shorter spans. One way of dealing with this challenge is by providing more support to the beam. However, this strategy is inconvenient, especially when a large floor area is required such as the case of St Pauls Cathedral. The amount of concrete used to make a beam to support a given amount of load will be higher than in the case of a reinforced beam. Hence, the cost of constructing beams for supporting loads in a multi-storey building such as St Pauls Cathedral using plain concrete becomes prohibitive. Hence, reinforcing becomes necessary.
Traditionally, reinforcing was done using steel bars, which provided the required strength in tension. With a reinforced beam, the span, which can support an equivalent load with a non-reinforced concrete beam that has equal cross-sectional dimensions, is higher. The need to increase such spans even higher gives rise to the need for a pre-stressed concrete, which will be most applicable in the construction of flying buttresses, landings for cones and domes, and piers in case of St Pauls Cathedral if it were to be done today.
Constructing the cone for the cathedral would not make use of stones as one of the material selection alternatives. Concrete is the prime material that is deployed today in the construction of structures that carry loads of overriding components. Building St Pauls Cathedral today would require significant implications in terms of cost, strength requirements, and material availability. This situation would create the necessity for the deployment of pre-stressed concrete instead of precast concrete. Wren would definitely consider Freyssinets plan to improve the cathedrals building technology.
From 1928 to 1933, Freyssinet made the most significant achievement in the development of pre-stressed concrete. These achievements were due to the discovery of double-actuated hydraulic jacks that were deployed to stress concretes high tensile wires. The accomplishments also followed the discovery of vibration methodology that was deployed in producing high-strength steel (Raju 2). These discoveries marked the beginning of the intensive spread of the practical applicability of pre-stressed steel since 1935.
Upon their realization of the effectiveness of Freyssinets methodology of pre-stressing concrete, civil engineers in the US and Europe began constructing long-span beams from 1945 to 1950. A good example of such a beam was deployed in the construction of Tamins-Reichenau Bridge in Switzerland. Building St. Pauls Cathedral in London using the pre-stressed concrete today requires Wren to manufacture pre-stressed beams just as he sourced stones, timber, lead, and wood among other materials. Manufacturing of pre-stressed concrete is done at a pre-stressing concrete plant.
Since beams would be required in the cathedrals construction, setting such a plant would make the cost of construction prohibitive. The best alternative entails contracting the manufacturing of beams to support the domes, cones, and other components of the cathedral. During the manufacturing of the pre-stressed concrete, the contracted civil engineers need to apply two ways of inducing compressive stresses in pre-stressed concrete. The first approach encompasses pre-tensioning while the second approach entails post-tensioning. In the pre-tensioning process, the concrete has to be placed after stretching of tendons.
Force that is used to pre-stress concrete has to be transferred to the concrete via a bond. In the pre-tensioning method, concrete is placed on the stretching steel. Mutsuyoshi and Hai suggest, To strengthen the beam, steel tendons with high strength are put in between two abutments to be tensioned to around 70 to 80 percent of their overall strength (167). Tendons are held in their respective positions by means of a tensioning force before the introduction of concrete into a mould.
Time would then be provided for the concrete to cure for it to gain the necessary strength. Tensioning forces would then be released. Steel produces a reaction after attaining the required strength from the concrete, thus making it gain the length that it had before. Consequently, tensile stresses are converted into compressive stresses, which upon complete curing of the concrete become very firm.
If they were to build the church today, manufacturers of the beams that were used to build St Pauls Cathedral would consider using post-tensioning methodology to induce the necessary strength in the concrete. In this approach, the concrete would be put after the tensioning and hardening of tendons before the steel is stretched. The resulting forces that characterize the pre-stressing would then be moved along the concrete supports (Mutsuyoshi and Hai 171).
Building the cathedral today would require the deployment of modern-day advanced lifting machineries such as hoist cranes. The building ground would be prepared using heavy earthmovers. With modern lifting machineries, the cone and even the dome would be cast and lifted into place while the decorations would also be moulded in place instead of being sculptured. Nevertheless, the painting of the dome, marble floor finishing, statues, various decorations on the window, altars, and the pulpit among other places would be done in the same way it was done in the 17th century.
The history of the tall building is very old. According to the Old Testament, in the City of Babel, people made a tower with bricks to save themselves from the flood. The tall buildings are the symbol of any countrys pride. This paper first tells about the historical background of tall buildings and discusses some famous high rise buildings. It further compares the structure of the buildings created in the past and present. The paper analyzes the problem in tall buildings and then discusses the rectification of those problems. It concludes that the advancement in computer and material science has made it possible to make high rise towers efficiently.
Introduction
The modern-day tall buildings symbolize national pride rather than being the embodiment of corporate wealth. The erection of super-tall structures in the Middle East and Asia that supersede the famous high-rise structures like the Empire State Building and the American Towers etc. denotes the idea of projecting the status of a country at the global level.
A building is a structure of walls, floors, roofs, and windows. A tall building is a multi-story structure in which most occupants depend on elevators [lifts] to reach their destinations. The most prominent tall buildings are called high-rise buildings in most countries and tower blocks in Britain and some European countries. The terms do not have internationally agreed definitions (High-Rise Building: Definition, Development, and Use, 2009, p.1).
Generally, a high-rise structure is considered to be one that extends higher than the maximum reach of available fire-fighting equipment. In absolute numbers, this has been set variously between 75 feet (23 meters) and 100 feet (30 meters), 5 or about seven to ten stories (depending on the slab-to-slab distance between floors) (High-Rise Building: Definition, Development, and Use, 2009, p.2).
Thesis Statement: Structure issues have been present in tall buildings for ages. This paper is an attempt to examine these structure issues under the following points:
History of tall buildings
Comparison between the old and new tall buildings structures with respect to the methods of construction, the material used, and their architectural designs
Problems occurring in tall buildings and possible solutions to minimize such problems
History of tall buildings
It is mentioned in the Old Testament that after the Flood, people at that time wanted to create a new city by the name of Babel. They wanted a tower to be made which could reach heaven. That tower was made with bricks, stones, and tar (High-Rise Building: Definition, Development, and Use, 2009).
During the era of the Roman Empire and in the reign of Julius and Augustus Caesar, many apartment buildings were constructed. Collapsing buildings became a frequent story due to structural failure. As a result, the laws were passed, and the heights of the buildings were limited to first 70 feet and then to 60 feet.
The history of such buildings says that there have been many other tall structures like towers, pyramids, cathedrals, and castles, but skyscrapers were created only by the end of the 19th century. One hundred and fifty years ago, the structure of the buildings in which people used to live or work was very different from todays buildings. The height of such buildings used to be rarely over a flagpole.
In the middle of the 19th century, two major developments took place that encouraged the construction of skyscrapers at a large level throughout the world:
Elisha graves Otis, an American, invented the first elevator in 1853. This helped people to travel upwards speedily and without much effort as required in walking.
The steel frames were introduced as a substitute for cast iron and wood in the 1870s.
The two of the tallest buildings were constructed in 1930 and 1931. They were Chrysler Building (319 meters) in New York City and Empire State Building (381 meters). After this 40, 50, 60 story structures were constructed in the whole of the United States. In the late 19th century, most of the buildings structure was based on steel frames (Moon et al., 2007).
Comparison between the Old and New Tall Building Structures
There have been many changes in the structure of the tall buildings since the very first high-rise building appeared. Presently, the structure and design made of glass, steel, and concrete is followed everywhere internationally. One of the main differences in the tall structures of the 1970s and 1980s is that the structural and architectural elements avoid regular repetition. In spite of the complexity involved in constructing the non-prismatic shapes, the past few decades have witnessed practicable use of products that are quite unusual in building the superstructures. Most of the non-orthogonal tall structures are erected with the purpose of marking them on the world map. These buildings generally have curved or organically shaped facades and distorted elevation. Architects have CAD modeling tools on hand, which is quite useful in constructing tall structures. In place of the conventional box form with rectilinear shape, modern architects are constructing many exciting and unexpected new shapes (Taranath, 2011)
The comparison can be made on the basis of the following three categories based on three generations of high-rise buildings:
First-generation: The external walls of these buildings were made of mainly stones and bricks. The use of cast iron was also prominent for decorative purposes.
The columns were made of cast iron, beams were made of steel or wrought iron, and floors were made of wood.
In the event of a fire explosion, floors could collapse, and the iron frame would not be that strong to hold anything.
A single stairway could be used for escaping from the floor.
Second generation: The Metropolitan Life Building (1909) and the Empire State Building (1931) belong to this generation. These buildings are the frame structures.
Riveted-steel columns and beams are used in the whole building.
These structures are considered extremely strong, but their floor space is not much attractive.
Third generation: Buildings which were constructed after World War II till today are the most current high-rise buildings.
Steel-Framed Core Construction: In such type of building construction, lightweight steel and concrete frames are used. In the center of these buildings, an inner load-bearing core is created. With this central code, the utilities and services of the buildings are attached.
Steel-Framed Tube Construction: Tube structures changed the design of steel-framed buildings. They are so strong that they can control the lateral forces of wind and the effects of the earthquake.
Reinforced Concrete Construction: Concrete, which is made tough against embedded metal, is known as reinforced concrete. It is very strong for any construction.
Problems concerning tall buildings and their possible solutions
A building has to be a secure place for working or living. Therefore, it is very important to focus on the probable tribulations that may arise during the construction of a tall structure and find their possible solutions.
Wind excitation: The most important factor in the construction of tall buildings is to choose the structural system that would defend against the lateral load. Tall buildings, being supple structures, need extra attention with respect to their response to wind excitation. Therefore, their dynamic response to wind excitation is critical in assessing their loading and performance particularly with respect to buildings deflections and accelerations at the top occupied floors (Taranath, 2011,p.452). There can be a cross-wind response and along-side response in this situation. However, the across-wind response is more pervasive in this background. The present-day computer-based geometric designing of tall buildings have transformed the shaping of tall structures perpetually (Taranath, 2011). Improving aerodynamic properties of tall buildings can lessen the effect of wind forces carried by them (Ali & Moon, 2007).
Comfort: The wind load can cause vibrating sway in the tall buildings. If the load is strong and constant, it may result in the development of cracks in the concrete and consequently make the structure fragile to further sway. There is a possibility of people to feel motion sickness in such buildings. Therefore, it is important to create aerodynamic structures to make them stronger against sway. While creating such tall structures, the frequency range should be kept under consideration (between 0.1-1.0HZ).
Load distribution: In a tall structure, load transfer from the surface to the foundation is influenced by all the significant stabilizing components of that building. The floor slabs are firm and unbending. Their bond with the vertical stabilizing components is helpful in dispensing the load between the mechanism that makes the tall structure firm and stable. However, it is important that the assumed solidity of the floor slabs should correspond with the real slab. The uncertain correspondence of slabs combined with the uneven load leads to force distribution, specifically in tall buildings.
Twisting and open cross-connections: To stabilize tall buildings, engineers use various stabilizing coordination in their construction. Generally, there is a stabilizing tower in the middle of the tall buildings. However, it is difficult to calculate problems related to load distribution at the center in cases of changes. The open cross-sections like U-shape and L-shape experience unbalanced pressure and are subject to unexpected distortion in the opened towers. The tall structures have an adverse effect due to larger rotation along the elevation. The twisting effect can lead to the displacement of the edges and overhanging in the axial and on the sides of the structure. However, the floor slabs work as supporting beams to avert this displacement.
Interaction between the soil and the foundation: The connection between the soil quality and tall structures is significant in view of the stability of the structure. Solid bedrock provides an entirely fixed foundation to a tall building. Foundations resting on the layer of clay are not considered as a permanent base for tall structures. In tall buildings, the piles are subject to move in a lateral direction and compress the soil due to their vulnerability to the vibrating sway. In such cases, it is important to maintain a stable bond between the soil and the piles to stabilize the structure.
Pierced shear wall: Shear walls are the firm stabilizing components of a tall building. It is evenly stiff, and it is easy to set up forces and moments and assume the linear pattern throughout the wall. However, the assumption of force distribution is not simple in pierced shear walls. Hence, it is wise to use an elastic method applicable to all types of pierced walls in common (Gustafsson & Hehir, 2005).
Conclusion
On the whole, the structure of tall buildings has been analyzed from many perspectives. It has been established that the advancement in computer and material science has given the solution for making taller and lighter buildings. Tuned Mass Damper is a very good solution for excessive wind-induced vibrations. The use of TMD has been beneficial for Taipei 101, and it has reduced the acceleration in the tower by 40% (Kourakis, 2005).
Except this, it is advisable that the structure should be able to bear the weight of the building in cases of accidents like fire. Other components of the building should protect it from collapsing immediately after the failure of any significant component (Taranath, 2011).
References
Ali, M.M. & Moon K.S. (2007). Structural Developments in Tall Buildings: Current Trends and Future Prospects, Architectural Science Review, 50 (3), 205-223
Gustafsson, D & Hehir, J. (2005). Stability of tall buildings.Department of Civil and Environmental Engineering, Web.