Larch (Larix decidua) bark insulation board: interactions of particle orientation, physical–mechanical and thermal properties

The current trend for sustainable utilisation of limited resources is stimulating the scientific research for previously neglected raw materials that could also be used for new value added products. Bark, which is a natural insulation material of trees, could be used as technical insulation material. This paper focuses on the effects of particle orientation in light larch (Larix decidua) bark insulation boards on their physical–mechanical and thermal properties. The experimental design is based on the variation of the particle orientation (orthogonal or parallel to the panel plane) and the board density (200–500 kg/m³). The mechanical properties, water absorption, thickness swelling and thermal conductivity of the boards were tested. The results showed a significant influence of the particle orientation and the density on the measured properties of the bark panels. This implies that the bark particle orientation is an important factor when producing insulation panels with specific characteristics. Suggestions for efficient use of bark particleboard are given.