Ecological insulation materials - Does sorption moisture affect their insulation performance?

A discussion about the sorption moisture affect on the insulation performance of ecological insulation materials is presented. To determine the relationship between thermal conductivity and moisture content, a sample of dry cellulose fibre was put into a hot plate for determining the thermal conductivity at 10°C. The heat fluxes at the sample mean temperatures 20, 25 and 35°C with a temperature gradient of 10°C were measured and the thermal conductivities were calculated. From these three measured thermal conductivities, the thermal conductivity for the dry material at a temperature of 10°C was determined by extrapolation.