In this study, mechanical, thermal and insulating properties of ultra-light thick particleboard (nominal density 250 kg m−3 and thickness 50 mm) made from sugarcane residues (bagasse) and wood planer shaving as a green building material (mainly based on renewable resources) were investigated. Urea formaldehyde and melamine-urea–formaldehyde resins have been used for board making. The results of insulating properties showed the absorption coefficient of sound for both bagasse and wood planer shaving particleboard increased as frequency increased, and noise reduction coefficient for all treatments was 0.313 and 0.365 for bagasse and wood planer shaving particleboard, respectively. Thermal conductivity for all boards was varying from 0.045 to 0.051 Wm−1K−1, and was in the range of insulation boards from other lignocellulosic materials. The results also showed that the boards from bagasse and melamine-urea–formaldehyde resin had the best mechanical properties. Finally, thermal conductivity and noise reduction coefficient for all treatments met the requirements of IS standard (IS 3129: Amendment No. 4 2006) for low density particleboard as a thermo- acoustic insulating semi- green composite.