Effect of Hygrothermal Transfer on Multilayer Walls Behavior, Assessment of Condensation Risk

Abstract:

Good insulation of envelopes in new or rehabilitated buildings represents one of the major issues in reducing the energy consumption in the construction sector. In order to ensure better insulation, a material compatible with the wall must be chosen to guarantees both good thermal insulation and reduction of humidity risk.This study reviews the risks related to moisture, particularly those related to condensation one occurring in buildings. Two stages were conducted during the study. Firstly, a coupled heat, air and moisture transfer model in a multilayer wall was developed. This model took into account both the discontinuity at the interfaces between the wall layers and the evolution of material properties depending on the water content. Then, applications to assess hygrothermal behavior of multilayer walls and predict of condensation risk into them were examined.Secondly, a parametric study was achieved on hygrothermal properties of insulation materials. The objective of this second stage was to evaluate sensitivity magnitude of different material properties on hygrothermal behavior of multilayers walls.This study focused on the most influential thermal and hydric properties in hygrothermal transfer model. Thus, thermal conductivity for heat transfer, total moisture permeability and moisture capacity to hydric transfer were selected.Finally, simulation results were analyzed and conclusions were derived on the effect of key parameters on the hygrothermal behavior in the walls and the conditions causing condensation risk to increase.

• Periodical: Advanced Materials Research (Volume 1051)
• Pages: 647-655
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1051.647
• Online since: October 2014
• Authors: Mohammed Yacine Ferroukhi*, Rafik Belarbi, Karim Limam
• Keywords: Condensation Risk, Hygrothermal Transfer, Multilayer Wall

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