Mycelium-bound ash sawdust biocomposite as a sustainable thermal insulation material for construction applications

Growing interest in sustainable construction materials has increased attention toward bio-based insulation systems with low density and renewable origin.This study presents an integrated experimental assessment of a myceliumbound biocomposite produced from ash sawdust and Ganoderma lucidum as a potential alternative for selected non-load-bearing insulation applications.The fabrication process included substrate sterilization, controlled inoculation, incubation, and final drying to obtain stable test specimens.An exploratory laboratory assessment was conducted to determine density, moisture content, thermal conductivity, volumetric heat capacity, thermal diffusivity, compressive response, and indicative fire-response parameters.The average thermal conductivity was approximately 0.054 W•m⁻¹•K⁻¹, placing the material within the broader range reported for lightweight bio-based insulation materials, although above the level of high-performance synthetic foams.Compression testing indicated moderate mechanical resistance potentially suitable for selected non-load-bearing applications.Fire testing confirmed combustible behavior of the present formulation, indicating that further improvement in reaction-to-fire performance would be required for broader construction use.Overall, the results identify mycelium-bound ash sawdust composites as a promising renewable insulation concept.However, further studies on long-term durability, moisture resistance, dimensional stability, biological resistance, and reaction-to-fire optimization are necessary before practical construction implementation can be considered.