Acoustic characterisation of a novel wood/cork composite material for architectural applications.

Acoustic materials for architectural applications are typically chosen for their performance, durability and aesthetics. Most of the common sound absorptive materials result from energy-intensive transformations of non-renewable resources, which respond poorly to the contemporary demands for an environment-friendly built environment. This paper describes a novel material for architectural acoustics, which combines wood and cork into a sustainable layered composite. This new type of material can be easily machined and offers opportunities for advanced customization, and in turn, for high control of its acoustic response. In order to achieve this, the normal impedance absorption coefficients of the composite and its individual constituents were measured in an impedance tube. In particular, the paper focuses on the contribution of different design parameters (performance variables), such as the layer thickness, the open area, and the depth of the air cavity. The results show that the composite materials, with cork behind perforated wood, forming a resonant absorber, perform significantly better than cork alone.