Benchmarking of the advanced hygrothermal model hygIRC – large scale drying experiment of the mid-rise wood frame assembly: report to Research Consortium for Wood and Wood-Hybrid Mid-Rise Buildings

Constructing mid-rise wood-frame buildings will extend the exposure of the structural wood components to moisture and its effects during the construction phase, unless additional measures are implemented to prevent this from occurring. This means that the wood-based components of the walls will be more exposed to wind-driven rain. Designers should consider these effects when designing and specifying components and systems. A good understanding of material behaviour will significantly minimize the effects of moisture on the building when constructed. However, during construction phase, it is important to prevent the wood studs and wood panels from exposure to moisture for prolonged periods. For example, moisture can be stored in the building envelope components during the construction process. The wood studs can be wet during the construction, and not dry sufficiently before the interior finish is installed and painted. The building materials can get wet during construction due to rain, or by lying on the damp ground. The question to be answered in this report is “how long does the high moisture content of the wood-based elements would take in order to be less than the acceptable limit to enclose and finish the wall (19% moisture content) so as to minimize the risk of biological damage to the wood structure? Furthermore, this report will focus on an experiment of drying potential of an insulated wood-frame wall with spray-in place foam and with initially wet wood studs.