INFLUENCE OF MOISTURE CONTENT OF MHM SOLID WOOD WALL CONSTRUCTION MATERIALS ON THERMAL CONDUCTIVITY
Keywords:
moisture status of materials, thermal conductivity, MHM solid-wood panels, wood-fiber insulation, straw insulationAbstract
The moisture content of materials in building structures is a factor that affects the amount of heat losses through the building envelope. In the context of the current demands for increased thermal protection, the moisture content of materials becomes an important indicator of thermal and technical properties. The paper is devoted to the theoretical and experimental analyses of the moisture condition of the construction materials of panel exterior walls made from solid MHM (Massiv-Holz-Mauer) panels. The theoretical analyses of the moisture status of materials through the WUFI 2D simulation program were supplemented by experimental measurements of moisture in built-in structures. The measurements took place in a research building simulating the creation of residential climate conditions. The research quantified the influence of the operating moisture status of MHM and blown thermal insulations (wood fibres and disintegrated straw) on their thermal conductivity. The research results show that the moisture content of MHM panels influences their thermal conductivity in natural conditions. However, in the case of wood-fibre insulation, no significant influence of moisture status on the coefficient of thermal conductivity was demonstrated. The moisture content of disintegrated straw indicates that in natural conditions, it acquires 46% higher thermal conductivity values than the ones declared by the manufacturer.
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