A particular advantage of numerical simulation is that the investigation of constructions consisting of different materials under various climatic loads requires relatively little work in comparison to field experiments. Thus, a hygrothermal assessment of constructions can be evaluated in a short time. Construction building details and building materials can be optimized using the numerical simulation, and renovation measures can be planned. Since the quality of simulation results depends on known hygrothermal material parameters, there is a great need for reliable material functions.

The present paper describes a database of hygrothermal material property functions for numerical simulation tools. The proposed multimodal physical functions for the thermal properties and the complete moisture storage and transport in the hygroscopic and overhygroscopic range are available for more than 70 building materials.

The distinguished phase transport functions are separated into liquid and vapor phases. The chosen functions are able to smooth and interpolate between scattered measurement data and provide a complete, unbroken, and consistent description of the material. The verification of each material data set, where the proposed functions are evaluated by independent transport measurements, is an advantage.

Presented at Thermal Performance of Exterior Envelopes of Whole Buildings X – December 2007

Units: SI