FACTORS AFFECTING CONSTRUCTION TIME PERFORMANCE AND BUILDABILITY OF HIGH RISE COMMERCIAL BUILDING PROJECTS IN SINGAPORE

Abstract

In the Budget 2010 announcement, the Singapore Government set the target of two percent to three percent productivity growth over the next decade to drive the 60 per cent of future Gross Domestic Product (GDP) growth. Currently, Singapore’s productivity level is 50 percent to 60 percent lower than countries such as Japan and the United States of America in sectors like manufacturing, services and construction and the construction industry is deemed to be one of the least productive industries in the country. This could be due to the heavy reliance on foreign workers as well as the limited use of advanced technology. As a result, the government has placed a strong emphasis on buildability, which can improve the efficiency of work carried out and in turn leads to higher productivity. Thus, the Buildability Framework was enhanced as part of the four-pronged approach of the Construction Productivity Roadmap. The purpose of this research study is to identify the underlying issues affecting productivity – the factors affecting construction time performance and buildability, particularly of high-rise commercial building projects in Singapore. To achieve the objective, the perception building construction practitioners regarding the topic is gathered and further analysed through a statistical analysis called the Importance Index. To determine whether there are any statistical difference between the categories of buildability and constructability identified, a variance test (F-test) was carried out. Through these methods, the effects and relative influence of the categories of buildabilty as well as the categories of constructability examined are determined. In order to achieve the viewpoints of the experts, questionnaires were distributed to 150 construction related companies and of which, a total of 25 valid replies were received, representing a response rate of 17%. 2 followed up interviews were then carried out to validate the results gathered through the survey questionnaire.

The analysis revealed that cost was the top factor affecting construction time performance and buildability as well as constructability of high-rise commercial projects in Singapore. Other important factors for buildability and constructability includes contractor’s experience, subcontractor’s competence, construction methods, building types and site conditions Insufficient sample size gathering experts’ opinion contributed to the limitation