Moisture based determination of the design value of thermal conductivity based on the delared values for thermal insulation materials in typical building constructions

The project is financed by the Danish Energy Agency's programme on thermal insulation methods that are friendly both to the external environment and to the working environment. The purpose of the project is to create a basis for determining the practical thermal conductivity for insulation materials by taking into account the moisture that is found in building constructions under typical conditions. The determination of the practical thermal conductivity will mainly be based on theoretical calculations of heat and moisture conditions in selected building constructions. The method is developed for generic insulation materials, but will mainly be used to examine conditions in constructions with alternative insulation materials, e.g., cellulose fibre, sheep's wool, and flax, which by nature have a substantial amount of hygroscopic moisture. Determination of the practical thermal conductivity is of importance for the manufacturers of insulation materials, especially the alternative insulation materials.