Modeling the hygrothermal behavior of biobased construction materials

Abstract

Materials with high moisture exchange capacity may have a strong impact on indoor climate conditions as well as building energy performance. Crop-based materials, characterized by their high porosity and hygroscopicity, belong to this category. Modeling their hygrothermal behavior accurately is thus particularly relevant for appropriate building design. A COMSOL Multiphysics transient heat air and moisture model is developed in this article to simulate moisture exchange between a lime–hemp concrete block and surrounding air during a Moisture Buffer Value evaluation test. Results are then compared with the validated heat air and moisture software using performance criteria showing a slight preference for both moisture exchanges and latent heat effect characterization. It offers yet additional advantages in terms of flexibility and transparency as well as further evolution potential.