Contribution to thermal and acoustic characterization of corn cob for bio-based building insulation applications

The introduction of the sustainability principle in building design is driving more and more the research towards the development of thermal and acoustic building insulating materials using natura or recycled-based materials and reducing as small as possible energy consumptions during the processes. In this context, among the mostly investigated materials, the corn cob plays an important role although its applications for insulation purposes are not yet fully developed. Moreover, the corn cob is often investigated as an aggregate of composite materials, therefore its own thermal characteristics are scarcely investigated. The goal of the paper is to provide a comprehensive contribution to the knowledge of this natural material, from a multidisciplinary point of view, by experimentally assessing at both micro and macro scales, specific heat, thermal conductance, thermal conductivity, and sound reduction index. Results show the specific heat can vary from 1.4 to 1.9 J/gK, according to the given temperature and the investigated corn cob layers, while density is around 200 kg/m3 and the conductivity, according to the investigated configurations, ranges from 0.14 to 0.26 W/mK. This work suggests a strategy to adopt for the evaluation of natural materials for building construction applications.