Thermal properties and Life Cycle Assessment of new eco-sandwich panel for building thermal insulation

Lightweight eco-materials are in high demand in many sectors, such as aerospace, industry, and building due to their several characteristics. The present paper is an experimental investigation of the thermal characteristics of novel sandwich panels made with local and ecological materials namely agglomerated cork for the core and bio-composite materials for the skin. Three configurations (symmetric, asymmetric, and two layers) were studied with different cork core thicknesses. Density values have been measured and compared. Thermal characterization consists of determining thermal conductivity and specific heat using a HFM apparatus; whilst thermal diffusivity and thermal effusivity have been calculated using the experimental findings. The panels are lightweight and thermally insulating. The values of thermal conductivity are in the range 0.071 and 0.102 W.m⁻¹.K⁻¹. The comparison between experimental results of thermal conductivity to theoretical values highlights the accuracy of method for multi-layer thermal characterization and the good adhesion between layers. Finally, a life cycle assessment of the new sandwich panels has been carried out and compared with common insulation materials. The sandwich panels are efficient in terms of embodied energy and CO₂ emissions compared to commercialized insulators and some insulators based on recycled or natural materials, the embodied energy for symmetric configuration with 4 cm cork core are 79.73, 94.75, and 89.35 MJ/FU corresponding to an embodied carbon 5.33, 6.32, and 6.01 CO₂/FU respectively. They can be classified in the middle between synthetic and natural insulators. Based on the findings, it was concluded that utilizing these sandwich panels as construction materials for interior paneling or partition walls could offer benefits in terms of being environmentally sustainable and cost-efficient.