LIFE CYCLE COST ANALYSIS OF GREEN BUILDING PROJECTS IN SRI LANKA

ICSBE 2023 LIFE CYCLE COST ANALYSIS OF GREEN BUILDING PROJECTS IN SRI LANKA CV Rajasekara1*, DVH Dodangoda 2, WN Kawmudi 2 1 Department of Quantity Surveying, Faculty of Built Environment and Spatial Sciences (FBESS), General Sir John Kotelawela Defence University, Southern Campus, Sri Lanka 2 Department of Quantity Surveying, Faculty of Built Environment and Spatial Sciences (FBESS), General Sir John Kotelawela Defence University, Southern Campus, Sri Lanka *Correspondence E-mail: [email protected], TP: +94715950494 Abstract: Increasing green construction adoption is at the forefront of the global building industry as society pushes towards greater sustainability. Green building has risen to the top of the priority list for the construction sector as the globe advances towards greater sustainability. While Sri Lanka is now experiencing an energy and economic crisis, green building ideas can support the economy by advancing the building industry. If Sri Lanka adopts the green building concept within the next 30 or 40 years, it might be able to transform revenue-generating prospects in the construction industry. People only take into consideration the construction's initial cost, not the total cost over the course of its whole life. It is preferable to consider a building's Life Cycle Cost (LCC), which includes cost parameters for maintenance, operational and services cost parameters. Therefore, the main objective of this study is to identify the factor that has the most impact on LCC in a green building and to provide solutions to reduce that factor's impact to further reduce LCC. The necessary authorities were surveyed using a questionnaire and interviewed online, allowing for a full analysis of the study. This uses both quantitative and qualitative analysis to validate findings and offer suggestions based on opinions from many parties in the building industry. The services cost was the cost data for LCC that is most affected, according to the studies. Further, this study made suggestions for reducing expenses in sustainable building to ultimately lower LCC. This research study will be relevant for Sri Lanka to address the current economic crises by taking monetary account of the green construction idea. Keywords: Green Building; LCC; Services cost; Maintenance cost; Operational cost ICSBE 2023 1. Introduction The development of green buildings is a crucial strategic move toward attaining sustainable development, energy and resource conservation, and environmental preservation. To encourage the healthy expansion of green buildings, many nations have produced green building grading guidelines (Liu, Guo and Hu, 2014). According to the World Business Council of Sustainable Development, buildings utilize 40% of the energy consumed worldwide(Geoffrey, Tathagat and Dod, no date). Numerous studies on sustainable building have been conducted with the goal of looking at ways to lower the amount of energy used in the construction sector (Tathagat and Dod, 2015). The advantages of economic efficiency the initial cost of green buildings can be reduced due to integrated energy solutions and smaller systems (Waidyasekara and Fernando, 2012). There are considerable advantages to green buildings over non-green structures, according to several research concerning green buildings (Simpeh and Smallwood, 2018). Additionally, lower yearly fuel and electricity expenses because of the decreased need for modern energy systems and peak power, as well as reduced yearly fuel and electricity costs, lower consumer energy prices are the outcomes (Waidyasekara and Fernando, 2012). Sri Lanka is going through a significant economic and energy crisis. The economy of Sri Lanka is collapsing. Green building ideas are currently popular topics since they can help the economy by supporting the building sector. In conventional buildings, most items are destroyed during renovation, but green buildings' features can be used as reusable parts. Prior to 30 or 40 years, if Sri Lanka adopts a green building concept, there may be a chance to transform this into a revenue-generating possibility on new development. In relation to the present energy crisis, it might be of great assistance(Geoffrey, Tathagat and Dod, 2015). Building construction typically takes between three and four years. On the other side of hand, a building's useful life can last 60 to 70 years. There are also additional expenses for upkeep, overhaul, and repairs during a building's lifespan. It's crucial to include both the construction cost and the life-cycle expenses when comparing the expense of a green building with a conventional structure. The evident economic benefits of green buildings include a shorter time to pay back due to reduced water, energy, and health expenses, as well as a speedier return on investments and increased income. Because green buildings consume less energy and water and can maintain their buildings for less money & they have lower operating costs(Geoffrey, Tathagat and Dod, 2015; Tathagat and Dod, 2015). Green buildings cost 37% more to build than conventional ones, but they also cost less to operate, maintain, and demolish, saving 28%, 22%, & 11%, respectively(Weerasinghe and Ramachandra, 2018). This concept of green construction, however, is not well known in Sri Lanka. They largely employ traditional building techniques because of their inexperience, lack of knowledge, inefficient procurement procedures, and lack of specialists with the necessary training. People just look at the project's beginning costs, not all the costs over its life cycle(Tathagat and Dod, 2015). A pilot survey was conducted to compare life cycle costs (LCC) between green buildings (university buildings) and non-green buildings (university buildings). The pilot survey's findings indicate that while the initial expense of a green building is more than that of a non-green structure, the green building saves money during its lifetime and is ultimately more advantageous. Then, utilizing sustainable development in the building sector might help Sri Lanka overcome its current energy and economic crises. Therefore, cost reduction through sustainable growth is a significant need now. The LCC is impacted by several things. The primary objective of this study is to determine the element that has the most influence over the LCC in a green building as well as offer ways to mitigate that factor to further lower the LCC. 2.Literature Survey Building construction typically takes between three or four years. On the other side of hand, a building's useful life can last 60 to 70 years. There are also additional expenses for upkeep, overhaul, and repairs during a building's lifespan. It's crucial to include both the construction cost and the life-cycle expenses when comparing the expense of a green building with a conventional structure. The entire cost across the asset's useful life is represented as a present value. The initial capital cost, financing costs, operating costs, maintenance costs, and eventual disposal costs for the asset are all included in this. All earnings and losses from the future are transformed to current values by using discounting methods (Goh and Sun, 2016). Initial expenses and recurring expenses for the project were considered in the LCC. 2.1 Initial Cost Capital expenses like purchasing land, constructing it, remodelling it, and purchasing the instruments required to complete the construction job might all be considered initial costs. Costs include day works, measured works, prime cost total, preambles, and preliminary sums(Fuller, 2006). Studies claim that the high cost of GBs precludes their widespread deployment in many nations. Initial costs for green buildings are 5–10% more than for conventional structures, with greater costs in the dwellings, academic and medical sectors. Green technology adoption by GBs is more expensive and time-consuming, which has created a bottleneck(M.S. Soujanya and H.AE.C Jayasena, 2018). According to,(Weerasinghe and Ramachandra, 2018). Construction costs for green buildings are 37% more than those for conventional buildings (Weerasinghe and Ramachandra, 2018). Due to a lack of understanding individuals in Sri Lanka only consider the project's initial expenditures rather than all associated costs over its lifespan. 2.2 LCC Cost Items Each category is advised to contain all pertinent expenses associated with keeping a building throughout its full life cycle, including operating expenses, expenses for maintenance, service expenses, and other expenditures like cleaning costs. These costs are then broken down into more precise cost components (Dwaikat and Ali, 2018). 2.2.1 Maintenance Cost All activities required to maintain a building's structure and individual parts in a manner that satisfies the minimal performance requirements are referred to as maintenance. It also covers all duties required to safeguard and preserve the building's structure. The overall cost of labour, supplies, and other expenses incurred associated with certain tasks and activities are considered the maintenance cost (Weerasinghe and Ramachandra, 2018).Direct labour, materials, fuel, equipment, and bought services are all included in maintenance expenses. Typically, maintenance expenditures may be divided into smaller categories such as routinely scheduled maintenance, unscheduled maintenance (fixing problems) & and intermittent upkeep (for significant life renovation) (Woodward, 1997). Although the costs of downtime are reduced by a regular, scheduled, preventative maintenance approach, resources are still utilized for maintenance expenses. The 'run it till it breaks' strategy, on the other side, lowers maintenance costs but increases downtime loss (Woodward, 1997). The ongoing maintenance and renovation of items requires money additionally. The amount of money required may need to be spent all at once or in cycles, depending on the kind of structural component and piece of equipment. Building maintenance should not be disregarded and should be done regularly. The expenses of dealing with various problems brought on by delayed maintenance are often substantially higher than the price of regular maintenance (Heralova, 2014). 2.2.2 Operational Cost Power, cleaning, insurance, management of facilities, and other related charges are included in a building's operating costs. The intensity of consumption, the nature of building activities, climatic conditions, and obviously thermal technical factors all affect electricity costs (Heralova, 2014). Electricity expenses, taxes, rent, insurance coverage, cyclical regulatory costs, sewerage cost, and other operating costs may be included in the operational category according to the International Standard ISO 15686-5:2008 (Weerasinghe and Ramachandra, 2018). As energy expenses, water expenses should be managed similarly. Water use expenses and water disposal expenses are the two main categories of water expenses (Fuller, 2006). The sewerage expense is the sum of a baseline price based on the annual cost of the business property and an excess fee based on average water use above 100 cubic meters (Rybka, Bondar-Nowakowska and Polonski, 2016). Utilizing water-efficient irrigation, water recycling, and water-efficient appliances are all important for water conservation (Illankoon and Lu, 2019). In practical application, it might be difficult to predict energy costs with accuracy during the design phase. It is necessary to make assumptions about use layouts, occupancy rates, and schedules since they all influence how much energy is used. Engineering analysis can offer details on how energy is consumed by a building at the preliminary design stage (Fuller, 2006). Building industry architectural design processes are time consuming due to issues with unreliable data, difficult software, and modelling techniques. Buildings consume 32% of all energy generated worldwide and produce 19% of all energy related greenhouse emissions (Doan et al., 2017). 48% of the total cost of the building's life cycle is made up of energy costs, which are more expensive overall than both the building and design costs combined. Reducing energy usage was shown to be the factor that had the greatest impact on reducing the overall life cycle cost(Dwaikat and Ali, 2018). 2.2.3 Services Cost Building services are essential to any structure, but they play a crucial role in green buildings as they directly contribute to most sustainability deliverables including water consumption, energy consumption, and indoor environment quality. Any sustainable building development and its consultants must carefully examine and optimize building service expenditure, which accounts for a significant portion of the cost (Illankoon and Lu, 2019). Building services fall mainly into three categories, in accordance with the new rules of measurement: drainage systems (above and below the ground), mechanical, electrical, and transportation (Illankoon and Lu, 2019). It is found that, in green building projects, although the customer must initially spend more money in modern technology, doing so results in monthly savings on utility bills when compared to the cost of a traditional structure(Kim, Greene and Kim, 2014). 3 Research Methodology It was found that the LCC of green buildings is less than traditional buildings according to the pilot survey conducted as the base for this research study. The study's main goal is to identify the main factor that affects LCC of green building projects and suggestions were made to identify ways to mitigate it to reduce the LCC even more. A questionnaire survey and online interviews were conducted with the relevant authorities which allowed for a thorough evaluation of the research. This is a combination of both quantitative (via questionnaire survey selected by stratified random sampling) and qualitative (via interviews selected by purposive sampling) analysis to confirm and make recommendations based on the views of different parties in the construction sector. 3.1 Data Collection Methods Data was gathered via a Google form that was disseminated via email messages, and messages on WhatsApp, Facebook, and Viber. Experts were given questionnaires to complete to obtain the proper responses to the questions. To rank the various points of view, gathered through "Likert Scale" (Kawmudi et al., 2021). A total of 50 close-ended questionnaires were sent (selected through stratified random sampling), & achieved 83.3% of respondents, including engineers, architects, project managers, quantity surveying professionals, and contractors. A purposive sample was chosen since the semi-structured interviews' objective is to choose people with more expertise and practical experience in the study's topic. Quantity surveyors, architects, engineers, contractors, project managers, and other professionals with experience in the construction of green buildings were among the professions that were covered by the interviews. 3.2 Data Analysis Methods Utilizing Relative Important Index (RII) analysis, which expresses the frequency of the factors that present challenges, the data collected through questionnaire surveys was analyzed. building sector in Sri Lanka. Information acquired from the interviews was analyzed using content analysis. RII = Ʃ5i=1 Wi x Xi A x Ʃ5i=1 Xi Eq. (1): Relative Important Index Source: (Gündüz, Nielsen and Özdemir, 2013) Wi-The weight that is allocated for each factor. Xi-Number of responses A-Highest weight On a scale of 1 to 5, the main elements were recognized as highly agree, agree, moderately agree, mildly disagree, and strongly disagree. Tables and graphs were used for the presentation. For ease of comprehension, the elements were identified independently using a cording technique. 4 Data Analysis The development of green buildings is a complicated task that requires the assistance of numerous parties with specialized knowledge in various fields. Therefore, discussing the experience regarding the target population's trades is crucial. 4.1 Background Findings The broad perspective of respondents, including their occupation and industry experience, was evaluated because, depending on the viewpoint of different persons, the replies to the problems may vary according to their knowledge and thinking abilities. 8.80% 2.90% 4.40% 16.20% 67.60% PM Eng Qs Arc. Cont. Figure 1: Respondents based on Profession. Subsequently determined whether the professionals had experience with working on green buildings. 20.60%, 79.40%, Yes No Figure 2:Experience of the professionals in GBs According to figure 2 over 70% of respondents said they had experience working in the field of green building construction. Then find out to gather the data on their experience in green buildings. The bulk of respondents, or 50%, had expertise with green buildings for five to ten years, and only 1.5% of experts had experience for more than fifteen years. A trustworthy random sample of construction industry personnel was then used to distribute questionnaires. 4.2 Rank the Main LCC-Related Items The study identifies three significant LCC-related cost factors for GB building in Sri Lanka. The literature survey identifies the LCC-related cost items, and 12 of them are designated to rank depending on the relative importance of their influence. The respondents' levels of agreement were used to calculate the Relative Important Index. The respondents’ survey responses were considered to determine their overall ratings for each factor. As shown in the below-tabulated forms, the criteria were determined using a coding scheme for quick identification and ranking. 34.04% 33.26% 32.7% Maintenance Operational Services Figure 3: LCC Parameters For GB buildings in Sri Lanka, the study highlights three important LCCrelated costs aspects: maintenance, operational, and services. The service cost is the greatest LCC parameter discovered, and the operational cost is a minimum LCC parameter, according to the computation resulting from the Relative Important Index. 4.2.1 Maintenance Cost Table 1: Ranked the maintenance cost items in GB construction according to the RII. Code M4 M3 M1 M2 Causes of LCC Based on system requirements, maintenance needs for building service components will be decided. The LCC will then benefit long-term from modifying the building services system at the design stage. The expenses of dealing with various problems brought on by delayed maintenance are often substantially higher than the price of regular maintenance. Selecting elements in the design stage with proper structural components will reduce LCC in the long term. LCC may be reduced over time by making element selections throughout the design phase with the appropriate equipment. RII 0.741 Rank 1 0.729 2 0.724 3 0.715 4 Based on system requirements, maintenance requirements for construction service components will be determined, and the LCC will then profit longterm from adjusting the building service system at the design stage (M4), according to Table 1. This item was ranked first in the LCC's maintenance cost list. According to the needs of the system, the maintenance requirements for each component of the construction service might vary (Illankoon and Lu, 2019). The second highest ranking LCC item in terms of maintenance costs was: The costs of addressing different issues brought on by postponed maintenance are frequently significantly higher than the cost of routine maintenance(M3). A building's routine upkeep is crucial and shouldn't be disregarded. The expense of dealing with various problems brought on by neglected maintenance is typically substantially higher than the cost of routine maintenance (Heralova, 2014). LCC may be lowered as time passes by making component selections during the design stage with the suitable equipment, according to the item with the lowest rank in the maintenance cost (M2). 4.2.2 Operational Cost Table 2: Ranked the operational cost items in GB construction according to the RII. Code Causes of LCC RII Rank O4 Even though the initial cost of a solar system increases, it will decrease the future bills and be advantageous for saving LCC in the long term. It may reduce long-term power expenses by altering the design early in the project, allowing more daylight to enter the structure's interior. Adopting water reuse techniques (ex: storm water harvesting systems, rainfall harvesting systems) will minimize the LCC in the long run. Operational cost of electricity usage will be differed due to different climatic conditions. System usage will be reduced by changing the type of the system, which will decrease LCC in the long term. The nature of the building activities will affect the electricity cost in the long term. 0.785 1 0.762 2 0.741 3 0.732 4 0.715 5 0.703 6 O5 O6 O2 O3 O1 Even if the initial expenditure of a solar energy system grows, it will lower future costs and be beneficial for saving LCC over the long run, according to the LCC item with the highest operating cost rank (O4). According to the LCC of the brought forward solar panel system, using solar panels with a minimal capacity would result in energy cost savings of 4%, while utilizing solar panels with the required capacity will result in energy cost savings of 54%. For residential structures, solar panels constitute an energy-efficient technique (Illankoon and Lu, 2019). Reducing long-term electricity costs by making design changes early stage was accomplished; enabling more daylight to reach the inside of the structure was the second-highest operating cost item which can be used to reduce LCC in long term(O5). The nature of the construction activities will have a long-term impact on power costs, making electricity the least impacted operational cost category (O1). 4.2.3 Services Cost Table 3: Ranked the services cost items in GB construction according to the RII. Code Causes of LCC RII Rank S2 Adding design alternatives for natural ventilation in the design stage will reduce LCC in the long term. The LCC will be reduced over time by adjustments to the specific type of HVAC system. 0.759 1 0.747 2 S1 The most impacted service cost item was determined to be the addition of design possibilities for natural airflow in the design stage, which will decrease LCC over time (S2). The LCC analysis may be used for choosing design alternatives and alternative building components including roofing, windows, and building envelope (Heralova, 2014). By making modifications to the kind of HVAC system, the LCC will eventually decline and was determined to be the service cost type that was least impacted (S1). Depending on the energy usage, the expense of energy is distributed across several systems. HVAC system accounts for 48% of this cost/saving. Credit for peak power demand reduction has a direct impact on the building's HVAC system (Illankoon and Lu, 2019). The interviewees 1 and 4 stated that “There are additional expenditures for services that have an impact on the LCC, such as those for heating systems, security systems, telecommunications, and other connected expenses”. The operational costs of a green building, such as cleaning, management of the facility, insurance, and sanitary expenditures, are higher, according to interviewees 2 and 3. Interviewee 5 further mentioned other costs that affect the LCC, such as irrigation cost criteria. According to the interviewees, by using energy-efficient equipment such as LED bulbs, LCC can reduce operational cost in the long term. And LCC depends on the electricity, HVAC, and heating systems. Then, when implementing those systems in a building, it is important to consider LCC. Green architectures further explain that throughout the design changes in the design stage, LCC can be reduced by adding alternative structural components such as more windows to get more natural ventilation and natural lighting. The respondents claim that there are problems with controlling recurrent costs, including problems with the law, inadequate planning, bad maintenance, and an inadequate degree of awareness about constructing alternatives, which can lower LCC in the long run. 5 Conclusion The construction industry has established green building as its foremost objective as the globe advances toward greater sustainability. Despite the economic and energy crises, Sri Lanka is now experiencing, the growth in the construction industry is because of the principal application of green construction. Through the pilot study, it was discovered that the maintenance, operational, and service cost parameters are the key three cost factors that have a long-term impact on LCC. There have been studies done in the past that focus on LCC factors in green buildings. However, the long-term impact of cost parameters on the LCC is still being determined. Through this study, it considers the influence of LCC factors on a green building that decreases LCC in the long term. Data from green professionals in Sri Lanka were gathered using google forms, questionnaires, and semi-structured interviews. The Relative Important Index (RII) was used to evaluate the data to determine the long-term impact of cost items on LCC. To facilitate rapid identification and ranking, the criteria were established using a coding system. The services cost was the cost data for LCC that is most affected, according to the studies. Further, this study made suggestions for reducing expenses in sustainable building to ultimately lower LCC. 6 Recommendations Green industry experts offer a list of suggestions for lowering LCC's ongoing expenses through this study. 6.1 Recommendations to lower the maintenance cost. ➢ Maintain the real green building criteria with routine maintenance. ➢ Choose components with the appropriate structural aspects throughout the design phase. ➢ Choose elements throughout the design process using the right equipment. ➢ To decrease maintenance, modernize building services. ➢ Utilize prefabricated materials and green-certified materials. 6.2 Recommendations to lower the operational cost. ➢ Use sustainable elements like photovoltaic (PV) panels, solar tubes and eco roofs, LED (light emitted diode) lighting, and rainwater recycling technology. ➢ Create storm water harvesting systems, systems for ventilation, natural lighting systems, documented energy usage, thermal transfer, and a power calculation plan. ➢ Use recycled wastewater and employ water treatment techniques to conserve it. ➢ Use solar systems to reduce electricity bills and reduce LCC costs in the long term. ➢ Use alternative structural elements, such as larger windows, it is possible to increase natural ventilation and lighting and it will reduce energy usage of the building. 6.3 Recommendations to lower the services cost. ➢ LCC should be calculated while installing HVAC systems within a building. ➢ Maintain environmental and construction-related legislative design, green building principles should be used in the planning process. ➢ Energy savings should be aided by more insulation in the walls, ceilings, and flooring. ➢ Utilize contemporary technologies for services. as an illustration, security systems. Perform further study on this topic to advance the industry's methods. Consequently, recurrent expenses as well as LCC may be decreased over time by utilizing the concepts and alternative design methodologies in the design stage according to the green professionals in Sri Lanka. Acknowledgement The Faculty of Built Environment & Spatial Sciences (FBESS), Southern Campus of General Sir John Kotelawala Defence University (KDU), deserves special recognition for its assistance and guidance in improving the research, as well as for all the interviewees who provided firsthand information about this study. References Doan, D.T. et al. (2017) ‘A critical comparison of green building rating systems’, Building and Environment, 123, pp. 243–260. Available at: https://doi.org/10.1016/j.buildenv.2017.07.007. Dwaikat, L.N. and Ali, K.N. (2018) ‘Green buildings life cycle cost analysis and life cycle budget development: Practical applications’, Journal of Building Engineering, 18, pp. 303–311. 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