Arnaud Evrard

Hygrothermal Performance of Lime-Hemp Wall Assemblies

Lime—Hemp (LH) composites are innovative building materials. They can be used in renovated or thermally upgraded as well as new buildings. This article reviews hygrothermal properties of LH wall assemblies and compares their transient performance to five traditional assemblies using WUFI ® simulation. While the annual quantity of energy was similar, LH assemblies showed a strong ability to improve indoor comfort.

Modeling the hygrothermal behavior of biobased construction materials

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.