This paper focuses on the issue of integrating two or three dimensional models of heat and moisture transfer in porous materials with whole building HAM model-ing. To assess this aim, this paper proposes a reduced order model to simulate 2D Heat, air and moisture (HAM) behaviour in porous material. The reduction method used is the proper orthogonal decomposition. The method is applied on a block of concrete. Reduced order model and large original model are compared. The results illustrate the significant value of model re-duction for modelling 2D heat and mass transfers.

The project “Aktivhaus“-residential estate in Kramsach focuses on (1) energetic aspects and measures to reach the “net-zero-energy-building” and (2) avoidance of low indoor air humidity in winter by using the moisture buffer capacity of loam. The latter is discussed in this paper and results are presented. This investigation includes laboratory measurements on material scale for the characterization of the used loam (sorption isotherm, diffusion resistance). Cross-validation of the building simulation model Dynbil with its hygrothermal wall model is conducted.