Wärme Und Feuchte Instationär - or 'WUFI' - translated into English, means heat and moisture transiency.   WUFI^® performs dynamic simulations of coupled heat and moisture transfer, providing realistic simulation of hygrothermal conditions in building components and buildings under actual climate conditions. WUFI^® is based on the latest knowledge in vapor diffusion and liquid transport in building materials.

The Department of Hygrothermics at Fraunhofer IBP has developed the WUFI^® software family for state-of-the-art hygrothermic analysis. WUFI^® performs dynamic simulations of coupled heat and moisture transfer. The methods have been validated world wide and provide realistic simulation of hygrothermal conditions in building components and buildings under actual climate conditions.

WUFI^® is based on the latest knowledge in vapor diffusion and liquid transport in building materials, even though the software requires only standard material properties and easy-to-determine moisture storage and liquid transport functions. For boundary conditions, measured outdoor climates – including driving rain and solar radiation – are used. Various types of models thus allow the analysis of multi-layer materials, component connections, and even multi-zone buildings under realistic exposure to natural weather conditions.