Condensation Risk within Loose Fill Insulation Due to Natural Convection in Vertical Cavities PDF

The paper presents a case study about the influence of natural convection on condensation risks and on mold growth risks within loose fill insulation of a wood-framed wall under a yearly climate cycle. The investigations were carried out using the WINHAM2D model, a two-dimensional heat, air, and moisture transport program without liquid transport suitable for noncapillary insulations. The results of WINHAM2D are compared with the German standard to show differences between both models and their results. As the focal point, the results of location, time, period, and extent of local moisture accumulation are considered. The purpose of the study is to give a first recommendation to avoid damage due to convective moisture redistribution under the coupled conditions of air permeability of the insulation and water vapor diffusion resistances of the boundary layers. The analysis indicates that material properties and boundary conditions have a significant influence on the dynamic process of the moisture migration within insulation.