Evaluation of Thermal Insulation Performance of Sawdust-Based Composites for Indoor Thermal Comfort

Abstract

The demand for indoor thermal comfort is growing by the day due to the impacts of global warming and increasing frequency of heatwaves.  This study investigated thermal insulation performance of sawdust-based composites for indoor thermal comfort, with a focus on identifying sustainable insulating materials. Samples of plaster of Paris (POP), laterite, and cement powder were collected and mixed together to form composite powder using sawdust as the primary constituent of the four composites – sawdust-POP, sawdust-cement, sawdust-laterite and sawdust-POP-cement-laterite. The specific heat capacity of each composite powder was determined using the method of mixture, while Lee’s disc apparatus was used to determine their thermal conductivity. Results revealed that the sawdust–cement composite recorded the highest specific heat capacity (5538 J Kg⁻¹ K⁻¹), followed by sawdust–POP (3636 J Kg⁻¹ K⁻¹), sawdust–laterite (2002 J Kg⁻¹ K⁻¹), while the sawdust-POP-cement-laterite composite had the lowest value (1819 J Kg⁻¹ K⁻¹). For thermal conductivity, the sawdust-POP-cement-laterite composite showed the lowest conductivity value (0.10 W/m·K), followed by sawdust–cement composite (0.17 W/m·K), sawdust–POP composite (0.18 W/m·K), and sawdust-laterite composite (0.19 W/m·K). The values of thermal conductivity of these composites are all below the 0.25 W/m·K -threshold, indicating their suitability for thermal insulation applications