Hygrothermal Modelling of Multi-Functional Wood Composite Panel (MFP): Comparison of Simulation Results with Field Measurements

A Multi-Functional Wood Composite Panel (MFP), made of laminated OSB as skin with wood fiber insulation core, has been developed as an innovative wall system for higher energy efficiency and structural performance. To ensure its long-term durability, full-scale field measurements of the hygrothermal performance of prototype wall systems have been carried out in two climatic conditions, i.e. Vancouver and Edmonton. A validated hygrothermal model is needed to evaluate the hygrothermal performance of the proposed MFP with various wall configurations under different climatic conditions than tested. This paper presents the comparison of simulation results of hygrothermal modeling using a commercially available program WUFI Pro with field measurements. Two types of MFP were tested: type A having a wood fiber as the insulation core, while type B having the Extruded Polystyrene (XPS) as the insulation core, and a conventional 2x6 wood frame wall was used as the datum wall for comparison. Comparisons show that simulation results predict the general trends well and the differences in moisture content (MC) of OSB between measurements and simulations are within 4.4%. There is no noticeable difference between replica, while distinct different between south and north orientations is observed. No significant difference is observed between type A and type B panels. The WUFI model can be used to evaluate the hygrothermal performance of the prototype MFP under other application conditions.