Modelling labour productivity of reinforcement bar using polynomial regression: A study on a tropical country's weather

For many years, the issue of environmental influence on labour productivity has received considerable attention. One of the most significant contemporary discussions in economics and construction management disciplines is about determining how weather factors influence labour productivity. While extant literature is replete with formulas and models applicable to the cold and hot climatic regions, there appears to be a paucity of useful models within the context of tropical countries such as Malaysia. With the increasing concern for climate changes and global warming, predicting how tropical weather factors may impact labour productivity is becoming an important research topic. This study developed a new model using polynomial regression based on actual data collected from a residential project in Kuala Lumpur, Malaysia. The study examined how rebar work is influenced by five weather factors: temperature, relative humidity, solar radiation, wind speed, and rainfall. The results show a 43% productivity variance due to weather factors. Further, the developed model shows how the interaction between weather factors can change the variability of productivity. The proposed model is useful for providing more accurate productivity predictions for construction management. This is useful to project planning and resolving disputes regarding progress claims.