Thermo-acoustic and fire reaction performance of eco-insulation panels made from window industry wood waste and natural animal-based glues

In the context of sustainable construction, the reuse of industrial by-products to produce eco-sustainable insulation materials has attracted growing interest. The study explores the thermal, acoustic, and fire-reaction performance of sustainable insulation panels produced using wood waste from window frame manufacturing and bonded with either commercial polyvinyl acetate (PVA) glue and natural animal-based adhesives (hide and bone glues). Three types of wood residues were tested — pine, mahogany, and mixed wood shavings — and formed into panels using optimized formulations. Thermal conductivity values ranged from 0.067 W mK −1 (mahogany wood-based panel with PVA glue) to 0.079 W mK −1 (pine wood-based panel with hide glue). Among the panels assembled from wood pieces, bone glue performed slightly better than hide glue in terms of thermal insulation, especially in mahogany-based samples; an opposite trend was observed in mixed shavings panels, where hide glue led to slightly lower thermal conductivity. Acoustic measurements showed high normal-incidence sound absorption coefficients, especially for mixed shavings with bone glue, reaching a Sound Absorption Average (SAA) value of 0.77. Transmission Loss (TL) also improved with natural adhesives, with mixed shavings panels characterized by TL values up to 28 decibel (dB)—significantly higher than those glued with PVA. Panels bonded with animal glues demonstrated markedly improved fire reaction performance compared to those with PVA: ignition times up to 57 s and average flame durations below 30 s were found instead of 14 s and 500 s of PVA, respectively. Moreover, PVA–wood shavings panels underwent severe post-flame smouldering, leading to a total mass loss up to 97%. • Eco-sustainable panels from window-industry wood waste using natural animal-based glues. • Thermal conductivity in the 0.067–0.079 W mK −1 range, comparable to bio-insulators. • Mixed-shavings panels with natural glue reach high acoustic absorption (SAA 0.77) and insulation (TL up to 28 dB). • Natural glues improve fire reaction with delayed ignition and short flame times. • Panels offer a circular, low-impact insulation solution for building envelopes.