Browsing by Author "Geekiyanage, D"

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Assessment of costs and benefits of green retrofit technologies
(Elsevier, 2023) Periyannan, E; Ramachandra, T; Geekiyanage, D
With the rising impact of greenhouse gas emissions, resource depletion, and the global interest in sustainability advancements within all sectors, construction industry practitioners are also interested in incorporating sustainable features and practices into their buildings. Nevertheless, most of the commercial buildings in Sri Lanka had been constructed during the unprecedented urbanization between 1995 and 2010, thus, before sustainable concepts became more prominent. Therefore, existing buildings in Sri Lanka is experiencing ever-increasing energy consumption, resulting in higher utility costs, with which green retrofitting has become imperative, notably in hotel buildings. This study, therefore, conducted an economic evaluation of three existing hotel buildings to establish an account of the cost implications and saving potentials of different green retrofit technologies. The data collected through document reviews and site visits were analysed using net present value and simple payback period calculations. Although number of retrofitting technologies have been incorporated in the selected buildings, more weight has been given to incorporating technologies to achieve energy efficiency and indoor environmental quality. Considering the financial viability, all the implemented green retrofits have a positive return on investment and less than ten years of payback period, except LED televisions. Amongst the implemented retrofits, biomass boilers, energy-efficient chillers, and solar PV systems have the highest energy-saving efficiency, followed by VFDs and LED lighting, while LED televisions have the lowest. The study's findings contribute to industry practitioners identifying the appropriate green retrofits based on the cost implications and savings potential and enhancing the sustainability of the built environments by reducing greenhouse gas emissions and depletion of natural resources.
item: Conference-Full-text
Building organisational capacities for effective e-waste management: a conceptual framework
Azeem, AHA; Mallawarachi, H; Geekiyanage, D
Globally, e-waste generation rises in parallel to the increased consumption of e-products. Management of this complex waste stream becomes a severe challenge, especially for developing countries. Sri Lanka also no exception to this problem due to the limited capacities of e-waste handling organisations in the country. Therefore, this study aims to develop a conceptual framework for effective e-waste management by integrating organisational capacities to improve the involvement of organisations for effective e-waste management. Initially, a comprehensive literature review was carried out on the state-of-art of the e-waste management, capacity buildings, and application of organisational capacities for e-waste management alike. The review of the literature revealed that there are eight dimensions to measure organisational capacities. They are mission and strategy, organisational structure, processes, human resources, financial resources, information resources, and infrastructure. The data collected from the literature review was manually analysed and finally, the conceptual framework was developed on organisational capacity buildings for effective e-waste management. The developed conceptual framework can be used as a guideline to implement organisational capacities for e-waste management. This framework will be a blueprint for individuals and organisations to incorporate dimensions of organisational capacity buildings to ewaste management by identifying the existing capacity gaps consequently, enhancing the organisational capacity for better managing the e-waste, especially in developing countries.
item: Conference-Full-text
Economic performance of green walls: A systematic review
(Ceylon Institute of Builders - Sri Lanka, 2022-06-24) Madushika, UGD; Ramachandra, T; Geekiyanage, D; Sandanayake, YG; Waidyasekara, KGAS; Gunatilake, S
Green walls are becoming an interesting solution to address the potential issues due to loss of greenery in the urban built environment. Even though green walls offer numerous benefits, the application pace of this concept seems slow in many parts of the world including Sri Lanka, which could be primarily due to the perception that the construction of green walls may involve additional costs compared to conventional walls and due to lack of awareness of its performance. This has driven the recent researchers to investigate the economic performance of green walls. However, those studies are limited to given local contexts, thus, the knowledge is scattered. Therefore, this paper aims to explore the economic performance of green walls in the global context collectively using a systematic review towards understanding the differences. Filtering the search for the period of 2010 to 2022 offered 15 out of 103 research articles suitable for the analysis. The cost data extracted shows high variability related to different characteristics of green walls, building envelopes, and climatic conditions. According to the review, the maintenance stage accounts for the highest portion of the Life Cycle Cost (LCC) in any type of green wall. The direct green façade is the cheapest option with lowest LCC compared to the indirect and living wall types while the living wall is the expensive type due to presence of more components. The review further confirms that in most instances, the economic benefits of green walls; increase property value, façade longevity, tax incentives, and energy-saving tend to offset the cost of green walls. It is expected that this collective review outcome would better guide the decision-making process of green wall implementation in a given context.
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Factors influencing acceptance or rejection regarding being the host community for post-disaster resettlements in developing countries
(Elsevier, 2021) Geekiyanage, D; Keraminiyage, K; Fernando, T; Jayawickrama, T
Post-disaster relocations have both positive and negative impacts on host communities. Receiving the host community's willingness to host the new community is essential to ensure integration and the sustainability of the new resettlement. This “willingness” is influenced by a variety of factors which have not been adequately studied by researchers and policymakers. This study, therefore, investigates the latent variables influencing a host community's decision to accept or reject disaster-induced resettlements. The study employed a survey approach utilising a questionnaire that contained 70 factors influencing host communities' perspectives on resettlements. A randomly selected 250 respondents from host communities were asked to indicate the factors that influence their level of agreement to be the host for displaced parties based on a 1–5 Likert-scale. The responses were analysed using the factor analysis: principal component analysis (PCA) and exploratory factor analysis (EFA) respectively. The PCA extracted 16 components which influence a host community's decision to accept/reject displaced communities (which account for nearly 70% of the total variance). The three most significant components were the impact on livelihoods and access to resources (total variance of 13%), political power and human wellbeing (9%), access to public services and social security (7%). The EFA revealed 58 sub-latent variables consisting of a majority of rejection factors (90%) with very few influences to accept displaced communities. The study's findings can be used by authorities and policymakers who design and implement post-disaster relocation programmes in understanding a host community's viewpoints and their involvement in making the resettlements successful and sustainable.
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A model for estimating cooling energy demand at early design stage of condominiums
(Elsevier, 2018) Geekiyanage, D; Ramachandra, T
Amongst the energy end-use sectors of an economy, residential buildings have become the dominant by consuming 50–70% of operational energy for Heating Ventilation & Air Conditioning (HVAC). Surprisingly, in Sri Lanka, energy consumption for space cooling accounts for more than 75% of electricity use in a typical building. Construction of condominium buildings in Sri Lanka has significantly increased in recent past and consequently, the demand for space cooling has increased. This energy demand is significantly affected by “Building design variables” such as building size, shape, orientation, height, window and roof area, and grouping of buildings. Thus, it is essential to estimate the energy required for space cooling based on building design variables at the early stage in order to obtain less energy consuming building structures by altering design variables. On this note, this study developed an early stage model for estimating cooling energy demand of condominiums in Sri Lanka, which is based on building design variables. A quantitative approach involving questionnaire survey and document review was adopted to collect data from 30 condominiums. A correlation analysis performed on collected data indicates that the design variables of number of floors, building height, building shape, grouping of buildings, window-to-wall-ratio, gross internal floor area, and wall-to-floor-ratio have significant correlations with the cooling energy demand of condominiums in Sri Lanka. Subsequently, a stepwise multiple linear regression analysis performed indicates that only number of floors and window-to-wall-ratio are responsible for over 91% of fluctuation in cooling energy demand. Therefore, using the developed model, the annual cooling energy demand of a condominium can be estimated and minimised, giving considerations to significant design variables that could inform decisions at the early stage to ensure energy efficient designs.
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Nexus between running costs and building characteristics of commercial buildings: hedonic regression modelling
(Emerald, 2020) Geekiyanage, D; Ramachandra, T
Purpose – Traditionally, early-stage investment decisions on buildings purely based initial capital costs and simply ignored running costs and total lifecycle cost. This was basically due to the absence of estimating models that yield running costs at the early design stage. Often, when the design of a building, which is responsible for 10–15% of its total cost, is completed, 80% of the total cost is committed. This study aims to develop a building characteristic-based model, which is an early-stage determinant of running costs of buildings, to predict the running costs of commercial buildings. Design/methodology/approach – A desk study was carried out to collect running costs data and building characteristics of 35 commercial buildings in Sri Lanka. A Pareto analysis, bivariate correlation analysis and hedonic regression modelling were performed on collected data. Findings – According to Pareto analysis, utilities, services, admin work and cleaning are four main cost constituents, responsible for 80% of running costs, which can be represented by highly correlated building characteristics of building height, number of floors and size. Approximately 94% of the variance in annual running costs/sq. m is expressed by variables of number of floors, net floor area and working hours/day together with a mean prediction accuracy of 2.89%. Research limitations/implications – The study has utilised a sample of 35 commercial buildings due to non-availability and difficulty in accessing running cost data. Originality/value – Early-stage supportive running costs estimation model proposed by the study would enable construction professionals to benchmark the running costs and thereby optimise the building design. The developed hedonic model illustrated the variance of running costs concerning the changes in characteristics of a building.
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Running costs indices for commercial buildings using the hedonic price imputation approach: a case of Sri Lanka
(Taylor & Francis, 2021) Geekiyanage, D; Ramachandra, T
Running expenses of a building consume a substantial share of its total life cycle cost and range between 70 and 80% in commercial buildings. Despite this, investment decisions are primarily based on construction costs due to the absence of a reliable estimate or forecast of costs inuse. In such a context, having running cost indices that incorporate building characteristics would enable investors to predict the running costs of a building at the early phase. This study is aimed at developing running cost indices for commercial buildings by taking Sri Lanka as a case. The running costs and building characteristics data were collected from a sample of 46 commercial buildings and analyzed using the hedonic price imputation approach, which enables the prediction of costs in absence of cost/quantity data. The hedonic indices developed in the study shows an increasing trend of running costs with varying degree of 0.37, 0.30, and 0.28% quarterly for offices, banks, and all commercial buildings, respectively. This prediction of trend would assist commercial developers to capture the movement of the running costs of commercial buildings and thereby optimize the running costs in the early design stage. This study further highlights the hedonic price imputation approach as a promising method for constructing index values where there is no adequate and reliable historical cost data.
item: Conference-Full-text
Significant factors influencing operational and maintenance (o&m) costs of commercial buildings
(Ceylon Institute of Builders, 2018-06) Geekiyanage, D; Ramachandra, T; Sandanayake, YG; Gunatilake, S; Waidyasekara, KGAS
Usually, the costs incurred during the operational phase of a building are much greater than the initial construction cost. Amongst, the running cost of a typical commercial building varies between 70-80% of its total LCC depending on its determinants. However, the significance of those determinants could vary with building function, characteristics of location and economy where it is based. This paper, therefore, investigates the significance of factors influencing the running cost of commercial buildings in Sri Lanka. A questionnaire survey administered to a sample of 125 industry professionals who have more than 10 years of experience in building O&M indicates that O&M costs of a commercial building are influenced by 08 major determinants including building characteristics (BC), maintenance factors (MTF), managerial factors (MNF), environmental factors (EF), political factors (PF), tenant factors (TF), design and & construction defects (DCD), and social factors (SF). The relative significance index (RSI) analysis performed ranked EF as the top determinant influencing both operations and maintenance costs of commercial buildings with an RSI of 0.963 and 0.996 respectively. Further, all the respondents are of the view that building function, occupancy, and building services have a highly significant influence on operations costs whereas natural deterioration, failure to identify the true cause of defect, lack of preventive maintenance, and budget constraints are foremost factors influencing the maintenance costs. The impact of most of the sub-factors except very few namely, building function, age, and location on O&M costs can be controlled up to a greater extent. Thus, early consideration of these factors during the building design and construction will result in reduction of unnecessary costs to be incurred during the operational phase of a building.
item: Conference-Full-text
A Simplified guide towards incentivising embodied carbon assessment: a case of high-rise residential building
(Department of Building Economics, 2024) Sachchithananthan, M; Ramachandra, T; Geekiyanage, D; Sandanayake, YG; Waidyasekara, KGAS; Ranadewa, KATO; Chandanie, H
In recent decades, the increasing threat of global warming has emphasised the importance of reducing carbon emissions within construction sector due to its significant impact. Despite efforts to mitigate climate change, the construction industry faces a critical gap in effectively evaluating the carbon emissions and costing it. The major reasons could be attributed to lack of awareness of carbon performance and commitment, lack of data availability and inconsistent methodologies. Hence, this study aims to develop a simplified guide, as an extension to the typical cost estimation practice towards addressing the above concerns with respect to embodied carbon (EC). This study primarily involved a quantitative assessment of EC emission of a typical high-rise residential building in Sri Lanka. Therefore, BOQ of the selected building and additional information such as material and machinery requirements, EC co-efficient, fuel consumption and transportation distance were obtained from technical specifications, industry practiced norms and databases. Accordingly, the EC emission of the selected building was derived as 873KgCO2/m2 of GFA. Of this, 94% is due to material production stage, while remaining 6% is in transportation and construction stages. Key materials contributed include: paint, cement and reinforcement. The steps followed in deriving the above estimation is presented as a simplified guide that would promote and account the construction clients for the EC emission of their proposed building constructions. By integrating EC assessment (ECA) into the construction cost estimation process, this guide seeks to empower decision-makers to choose among carbon alternatives and aid in carbon taxation in the Sri Lankan context.
item: Conference-Full-text
A study on the application of economies of scale in the construction industry: the Sri Lankan perspective
(Ceylon Institute of Builders, 2017-06) Ramachandra, T; Geekiyanage, D; Perera, SL; Sandanayake, YG; Ramachandra, T; Gunatilake, S
The application of economic concepts acts as a catalyst to enhance the productivity and quality in the industries such as automotive, transportation and tourism. Economies of Scale (EOS) is such a concept, which could be applied to address the above concern. This research therefore explored the application of EOS to the construction industry. The study adopted a qualitative approach by conducting structured interviews among 14 participants representing consultants and contractors in the construction industry. Subsequently, a content analysis was performed to analyse the data collected, with the aid of NVivo 11. Considering the views of experts, the application of EOS concept is limited to pre-cast elements in both building and civil engineering projects in the construction industry. Majority of the experts opined that application of EOS concept is limited in the construction industry mainly due to unawareness on applicability of EOS (71%) and unique nature of the construction industry (43%). Further, it was identified that uncertainties in the construction industry act as the major barrier to the application of EOS. Confirmation of drawings at the initial stage, conducting training sessions and researches are strategies to promote the use of EOS in the construction industry, which in turn would enable direct economic growth via price efficiencies.