Comparative analysis of the productivity levels achieved through the use of panelised prefabrication technology with those of traditional building system : a thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy (PhD) in Construction, School of Engineering & Advanced Technology, Massey University, Albany, New Zealand

Abstract

Several studies have documented benefits of prefabricated building system compared to the traditional approach. Despite the acknowledged benefits of prefabrication, its application is generally low in the New Zealand construction industry. This low uptake is largely attributed to the fact that the documented benefits of prefabrication technology are anecdotal, or based on investigations of isolated case studies. This study aims to contribute to filling this knowledge gap by analysing cost savings, time savings, and productivity improvement achievable by the use of panelised prefabrication in place of the traditional building system. A two-phased mixed method of research was adopted for the study. The first phase involved the use of case study-based archival research to obtain qualitative data from records of 151 completed building projects in three cities of New Zealand – Auckland, Christchurch and Wellington. The second phase involved the use of questionnaire survey to obtain feedback from industry stakeholders. Results showed that the use of panelised prefabrication in place of traditional building system contributed to 21 percent cost saving, 47 percent time saving and 10 percent average improvement in the productivity outcomes in the building projects. Results further showed that 17 factors could significantly influence the levels of benefits achievable with the use of prefabrication technology. ‘Building type’ and ‘location’ were the factors having the most significant influence on the benefits achievable by the use of panelised prefabrication in place of the traditional building systems. Other factors that influence the benefits of prefabrication included (in diminishing order of influence): logistics, type of prefabrication, scale/repeatability, standardisation, contractor’s level of innovation, environmental impact, project leadership, type of procurement, whole of life quality, site conditions, site layout and client’s nature.