Building Research Establishment Environmental Assessment Methodology and Leadership in Energy and Environmental Design

Buildings have each direct and indirect impacts on the environment.During the construction and service life of a shape raw materials, water, and energy are used. The constructions also generate wastes. A combination of these elements has prompted the development of exclusive green building requirements which aims to promote environmental sustainability.
Examples of successfully developed ranking systems are Leadership in Energy and Environmental Design (LEED), the ILF Living Building Challenge, GIGA Reset, Building Research Establishment Environmental Assessment Methodology (BREEAM) and several others. (Kolombo, Ilozor, and Robinson (2015) argue that these ranking systems have become the key drivers of innovation regarding sustainability in the construction industry
This paper focuses on comparing LEED and BREEAM rating systems, to establish the similarities and differences if there is. The comparison parameters are their rating systems, the potential for market acceptance, the relevance of the systems on a project cycle and their key impacts and shortcomings.Rating systems.BREEAMIn awarding of credits using BREEAM system, there are ten key parameters which are mandatory. Under these ten classes, there are a total of seventy-six related criteria, which may vary depending on the purpose of the building (Kubba, 2012). These parameters are energy efficiency, water utilization, construction materials, overall management, land use, transport, design innovation, waste and pollution control and health and well-being of the occupantsAccording to Colombo, Ilozor, and Robinson (2015), the assessment process begins with awarding marks for the mandatory criteria first before the tradable credits. It is worth noting that if any of the mandatory credit is missing, the overall rating automatically becomes zero.In each of the ten categories, the score awarded is divided by maximum obtainable score. The resulting value is then multiplied by a weighting factor which gives a percentage point score to two decimal places. Summation of the percentage scores for each parameter is done and the value obtained is the BREEAM’s certification score. (Colombo et al., 2015).BREEAM RatingsPercentage scoreUnclassified0 to 30Pass30 to 45Good45 to 55Very Good55 to 70Excellent70 to 85OutstandingAbove 85LEEDIn LEED system, seven main credits are subdivided into forty-three different criteria. The seven main categories are Indoor Quality, Water Efficiency, Energy Efficiency, Sustainable Sites, Construction Materials, Regional Consideration And Design Innovations. (US Green Building Council, 2009)In UGBC (2009) handbook, each criterion in the checklist has a minimum of one point out of a hundred points ( base point). The sum of the points is then used give the LEED rating of the structure as either certified, silver, gold or platinum (which is the highest rating) Potential for Market AcceptanceAccording to research conducted by Architecture Journal (as cited by Kubba, 2012), LEED has proved to be dominant green building standard in Europe and other emerging markets while BREEAM leads in the UK only. Kubba (2012) maintains that in markets of India and Brazil, BREEAMS efforts to penetrate have failed. On the other hand, LEED has certified a total of 142 schemes, with another 232 projects in progress to obtain accreditation. In Brazil, LEED had booked a total of 700 potential schemes by 2015. In total, LEED has successfully accredited 1350 project in Europe against BREEAM’s 646 projects.Since BREEAM is the primary measure of sustainability in the United Kingdom, it automatically scores higher than LEEDS. It has managed a record of 2365 projects including those which are accredited already and those that are in the process of certification. However, LEED is slowly gaining ground in the UK.Relevance of the Rating Systems to the Project CycleFor most infrastructural projects, a project cycle begins with planning and design and then contracting, construction, maintenance and operations and finally decommissioning phase. The relevance of a rating system to a project cycle can be determined by conducting a Life Cycle Assessment and Life Cycle Cost (Zuo & Zhao, 2014).Life Cycle AssessmentLife Cycle Assessment is used to determine the environmental impacts of the materials and products used in constructing a building. Zuo and Zhao (2012) maintain that green buildings certified by LEED and BREEAM are designed to efficiently utilize renewable sources of energy such as solar power, and natural lighting. Additionally, such structures are constructed with larger windows to allow sufficient natural light. An elaborate water and sewer system must be designed to ensure that water in the building is utilized efficiently and wastewater channeled for proper disposal. Due to the modification of designs to suit green structure design, the overall project cycle will be different from that of non-compliant buildingsLife Cycle Cost.Life Cycle Cost is concerned with the overall cost of a structure including the maintenance and demolition (if need be). Structures that have adhered to the LEED and BREEM construction regulations require lower maintenance cost since they have been designed to ensure that water is utilized efficiently, thereby minimizing wastage. Apart from that, the use of solar power and natural lighting are more sustainable over time (Kibert, 2016).Impacts of the Rating SystemsEnvironmental impactsBoth LEED and BREEM compliant structures have remarkable energy efficiency as high as 25% as compared to conventional buildings (Colombo et al., 2015). Additionally, their greenhouse gas emission is reduced by up to 34%. Since more structures are being renovated to become compliant with the rating system, it is expected there will be a significant reduction in environmental pollution with time.Social ImpactsAltmonte, Schiavon, Kent and Brager (2017) argue that BREEAMS main strength as a green building rating system is its numerous social benefits. Most of these sustainable buildings are aesthetically appealing. They are characterized by an excellent indoor air quality and sufficient natural lighting which create a perception of comfort. Other studies suggest that such a conducive environment In an office can increase productivity by up to 14% since the staff tend to be happyEconomic ImpactsGreen Building ratings are constructed to add sustainable value to a built environment. The effective utilization of natural resources significantly reduces the overall operation costs. Despite the fact that the developers can spend up to 6.5% more in coming up with green building compliant structures, the additional investment can be recovered in less than two years through water and energy bill savings only (Altmonte et al., 2017). Shortcomings of the Rating SystemsLEEDSA major challenge facing LEED is that some people believe that it is more of a theoretical concept that doesn’t work in most real-life cases (Kibert, 2016; Zuo 2014). These critics claim that the rating system relies heavily on energy models and projections and that does not necessarily translate to the construction of energy efficient models. The heavy reliance on energy model prediction also causes the system to have low adaptability, especially in areas that use alternative energy sources unlike those in the United States are likely to suffer low ratings. It is also worth noting that the minimum cost for accrediting a small building is $2900. Office and hospital building can cost an upward of $1 million (UGBC, 2009). The prohibitive expensive rates have also put into question its acceptability.BREEAMDespite the fact that BREAM is argued to be the green rating system with the highest adaptability, it has also received its fair share of criticism as documented by Colombo et al., (2015). First, the privatization of BRE has transformed the accreditation system into an unhelpful commercial activity. Secondly, there are other useless parameters which the system can give a high credit. A good example is the high credits given to buildings with bike racks and recycling systems. Such non-essential parameters may prevent the rating system from providing an accurate picture of a buildings energy efficiency and waste management.ConclusionBoth LEED and BREEAM are certified programs and are accepted worldwide to measure the sustainability of green structures. By comparison, it can be tough to handpick the differences between the two accreditation systems. However, upon a closer look, it is evident that there is a slight variation in the process of certification. It is also worth noting that LEED system has been adopted in more countries than BREEAM, despite the fact that BREEAM is considered more acceptable.ReferencesAltomonte, S., Schiavon, S., Kent, M. G., & Brager, G. (2017). Indoor environmental quality and occupant satisfaction in green-certified buildings. Building Research & Information, 1-20.Colombo, I., Ilozor, B., & Robinson, H. (2015). Environmental Assessment Tools: An Overview of the UK’s BREEAM and the US’s LEED. 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