Establishment of cost-benefit analysis (CBA) sustainable indicators for industrialised building system (IBS) projects: best practice / Siti Nur Atikah Abd Rashid

Sustainable development implicates satisfying the demands of the current population without endangering the capability of future population to meet their own needs. Many approaches were introduced to sustainable development which aimed to overcome the emergence of environmental issues in construction such as toxic generation, dust generation, and abundant construction waste. One of the sustainable approaches to help in minimising this problem, in construction is by using the Industrialised Building System (IBS) method. This method offers benefits such as reducing construction waste, lessening the construction time, minimising energy and water usage, decreasing the number of workers many and more. Regardless of the plethora of benefits, the adoption of IBS in Malaysia is still low mainly because of the cost itself. Hence, to promote the project’s viability via IBS, ideally, the benefits from adopting the method should be more reliable if they are presented in tangible (monetary) and intangible (non-monetary) value rather than descriptive, as this will subsequently contribute to gaining more interest for practitioners to choose IBS method, then increase the adoption of IBS in Malaysia. Relatively, there is a little attempt of studies in the measure of intangible or non-monetary criteria related to the benefit of IBS which critically requires a uniform indicator to standardise the measurement of intangible cost for IBS project. Therefore, cost-benefit analysis (CBA) can be used in order to identify the soft issues or intangible issues and elicit more transparency in IBS project. The study is aimed to establish the best practice incorporating sustainable indicators of CBA for IBS projects. The objectives of this study are to identify the indicators of CBA for IBS projects, to determine the rank of the CBA indicators for the viability of IBS toward sustainability, and to establish the best practice incorporating sustainable indicators of Cost-Benefit Analysis (SICBA) for IBS buildings. A quantitative approach is used in this study by using a questionnaire survey as the main instrument. The purposive sampling method is utilised to distribute the questionnaire to the respondents, comprises 30 suppliers of the IBS precast concrete system in Selangor and Kuala Lumpur. The survey has revealed that there are 31 indicators (11 monetary and 20 non-monetary) which can be emphasised as gaining the interest of the construction practitioner to adopt IBS. The top five most high rank in monetary indicators are the initial cost, compliance cost, operating cost, return of investment (ROI) and capital revenue income. It was also found that time, production, schedule, efficiency and buildability are the top five most high rank of the non-monetary benefits of IBS. This research proposed that the CBA model is one of many effective decision-making approaches to increase the adoption of IBS and its suitability towards sustainability in construction. It is hoped the result provides better guidance for the practitioners, such as government, developers, contractors and others to be aware of the crucial benefits of IBS, which is not only measured through tangible value but to also consider the non-tangible factors.