Investigating applicability of sawdust and retro-reflective materials as external wall insulation under tropical climatic conditions

Abstract

Buildings require energy to maintain their performance. In consequence, built environments cause a surge in the world’s energy demand. Providing passive measures is an efective method of optimizing operational energy usage. In this study, we propose insulation materials (thermal barrier type and resistive insulation) for the walls of a building. Experiments were performed on small-scale physical models constructed with; (a) no insulation, (b) sawdust–cement mortar, and (c) retrorefective (RR) material for external walls. In addition, regression models were developed to predict indoor air temperature with insulation. Subsequently, associated operational energy-saving and decrease in emissions were estimated for each material. The comparison reveals RR (sawdust–cement mortar) is efective in warm (overcast) climatic conditions. Developed regression models have shown a good agreement with experimental results (R>0.8). Moreover, sawdust–cement mortar (RR) materials contributed a 9% (13.4%) reduction in operational energy and a 9% (13.3%) decrease in CO2 emissions. The project highlights the potential to utilize sawdust—a waste material—and RR material as wall insulation to decrease intense operational energy demand.