Performance Comparison between Structural Element of Building Systems in Malaysia

The Industrialized Building System (IBS) was introduced in Malaysia in 1966, but it failed to establish itself on a continuous basis though there has been a sustained large market for residential projects even since. One of the reasons behind this shortcoming is the lack of scientific data on labor productivity that could convince policy maker. Hence, the objective of this study is to develop a standardized data collection methodology for measuring and comparing the conventional building system and IBS in term of labor productivity, crew size and cycle time. Labor productivity (man hours/m²) is defined as the man hours required to complete the structural element of one unit house. A total of 499 data points were obtained from seven residential projects constructed between January 2003 and April 2004. Analysis of Variance (ANOVA) indicated that the labor productivity was significantly different between four structural building systems. The mean labor productivity for the conventional building system was 4.20 man hours/m² followed by cast in-situ table form (2.70 man hours/m²), cast in-situ half tunnel form (1.88 man hours/m²) and pre-cast concrete system (1.33 man hours/m²). Further, the analysis of crew size indicated that the mean crew size of a conventional building system of 24 workers was significantly different from the IBS of 22 workers. However, the crew size within the IBS was found to be insignificant. The cycle time measured in days per house was found to be significantly different between structural building systems with the conventional building system of 4.9 days, cast in-situ table form of 3.9 days, cast in-situ half tunnel form of 2.9 days and pre-cast concrete system for 2.3 days. The labor productivity obtained from this study could be used as a preliminary guideline for a client or consultant to identify the most appropriate building system for executing a construction project and determining the labor requirement in the construction industry.