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
 Karade, S.R., Irle, M.A. & Maher, K., Physico-chemical aspects of the use of cork in cimentious composites. In ICWSF 2001- The Fifth International Conference on the Development of World Science, Wood Technology and Forestry, Ljubljana, Slovenia, pp. 97–106, 2001.
 Gil, L., Insulation corkboard for sustainable energy and environmental protection. Ciência & Tecnologia dos Materiais, 25, pp 38–41, 2013.
 Luis, G., Cortiça: produção, tecnologia e aplicação, 1998.
 Silva, S.P., Sabino, M.A., Fernandes, E.M., Correlo, V.M., Boesel, L.F. & Reis, R.L., Cork: properties, capabilities and applications. International Materials Reviews, 50, pp. 345–365, 2005. http://dx.doi.org/10.1179/174328005X41168
 Gil, L. & Cortiço, P., Characterization of insulation corkboard obtained from demolitions. Ciência & Tecnologia dos Materiais, 23, 2011.
 Jerman, M. & Černý, R., Effect of moisture content on heat and moisture transport and storage properties of thermal insulation materials. Energy and Buildings, 53, pp 39–46, 2012. http://dx.doi.org/10.1016/j.enbuild.2012.07.002
 Moon, H.J., Ryu, S.H. & Kim, J.T., The effect of moisture transportation on energy efficiency and IAQ in residential buildings. Energy and Buildings, 75, pp. 439–446, 2014. http://dx.doi.org/10.1016/j.enbuild.2014.02.039
 Chen, Z.Q. & Shi, M.H., Study of heat and moisture migration properties in porous building materials. Applied Thermal Engineering, 25, pp 61–71, 2005. http://dx.doi.org/10.1016/j.applthermaleng.2004.05.001
 Jelle, B.P., Traditional, state-of-the-art and future thermal building insulation materials and solutions – properties, requirements and possibilities. Energy and Buildings, 43, pp. 2549–2563, 2011. http://dx.doi.org/10.1016/j.enbuild.2011.05.015
 Srinivasan, K. & Wijeysundera, N.E., Heat and moisture transport in wet cork slabs under temperature gradients. Building and Environment, 36, pp. 53–57, 2001. http://dx.doi.org/10.1016/S0360-1323(99)00068-2
 ISO 10051:2008 Thermal insulation - Moisture effects on heat transfer - Determination of a thermal transmissivity of a moist material, 2008.
 Peuhkuri, R., Rode, C. & Hansen, K.K., Non-isothermal moisture transport through insulation materials. Building and Environment, 43, pp. 811–822, 2008. http://dx.doi.org/10.1016/j.buildenv.2007.01.021
 WUFI 2D 3.0. Fraunhofer Institut Bauphysik.
 EN 1602:2013 Thermal insulation products for building applications- Determination of the apparent density, 2013.
 NP EN 1936:2008 -Métodos de ensaio para pedra natural. Determinação das massas volúmicas real e aparente e das porosidades total e aberta, 2008.
 EN 12667:2012 - Thermal performance of building materials and products. Determination of thermal resistance by means of guarded hot plate and heat flow meter methods. Products of high and medium thermal resistance, 2012.
 EN 12086:2013- Thermal insulation for building applications - Determination of water vapour transmission properties, 2013.
 EN ISO 15148: 2012 Hygrothermal performance of building materials and productsDetermination of water absorption coefficient by partial immersion, 2012.
 ISO 12571:2013- Higrothermal performance of building materials and products - Determination of hygroscopic sorption properties, 2013.
 Künzel, H.M., Simultaneous Heat and Moisture Transport in Building Components One - and Two-dimensional Calculation using Simple Parameters, IRB Verlag, 1995.
 Torres, M.I.M., PhD Thesis Humidade ascensional em paredes de construções históricas, 2004.