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The promotion of more efficient and greener buildings and the reduction of energy consumption are among the priorities defined in the Europe 2020 Strategy. The potential of incorporating different types of waste and by-products in construction materials and solutions is relevant for achieving a more sustainable construction and use of buildings throughout their life cycle. Example of this, is the use of the medium density insulation cork board (MD ICB) as an external insulation coating material. It is a fully natural and recyclable insulation material, made from the exudation of cork granules, a sub-product from the cork industry. This material is sensitive to rain conditions as it absorbs water. When the energy performance of buildings is being assessed, the influence of moisture on its thermal behaviour should not be neglected. A building’s heat loss estimation can be far from reality if the materials’ moisture content is not considered. Therefore, it is of crucial importance to evaluate the drying behaviour of MD ICB after wetting this material. A numerical simulation, using WUFI 2D 3.0 was performed to evaluate the materials’ moisture content over time. In order to perform this study a thorough experimental characterisation of the material, in terms of hygrothermal parameters, was required. To validate the numerical model, the obtained numerical results were compared with experimental ones, in which MD ICB boards were dried in a climatic chamber, after being saturated with water. After the first 9 hours of drying, during which the moisture movement is mostly due to gravity, the experimental and numerical results present relatively good correlation.
cork, hygrothermal parameters, insulation materials, mass transfer, evaluation, numerical simulation
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