Danish moisture reference year for heat, air, and moisture simulations: Generation, comparison, and validation

Moisture is a crucial factor regarding degradation of building materials, and hygrothermal simulations are essential tools for analysing and predicting moisture content and durability of buildings under dynamic conditions. This article focusses on the development of a Danish moisture reference year, based on climate data from the period 2001 to 2019. The reference year was created as a “one-fits-all” for hygrothermal simulations and to ensure better representation of the Danish climate conditions. Traditionally reference years from nearby locations in Germany and Sweden have been used. The reference year was created according to EN ISO 15927-4:2006; the raw climate data was statistically analysed, and representative months were selected. This process resulted in five reference years, with focus on different types of constructions and exterior claddings. The new reference years were compared with reference years from nearby locations, as well as with the raw Danish climate data over a 9-year period. The analysis includes comparison of the climate parameters, and validation through dynamic simulations in WUFI and DELPHIN. In WUFI, simulations were made for typical wall and roof constructions, whereas DELPHIN simulations were made for three calibrated models from an earlier project, of internally insulated solid masonry walls. The results indicate that the five new Danish reference years were quite similar in many aspects (regardless of the chosen primary and secondary climate parameters) and provided a reliable representation of Danish climate conditions. For the hygrothermal simulations, a good correlation was generally observed between results from simulations using the Danish reference years and simulations based on raw climate data.