An in-situ hygrothermal investigation of an externally highly insulated enclosure in a cold climate with simulated extension to climate specific performance

High performance enclosures reduce building energy consumption, however, may vary from expected RSI values and be at risk of moisture damage. This research investigated the hygrothermal performance of a high performance enclosure for use in Toronto and other cold climates. The proposed enclosure utilized 228mm of exterior mineral wool attached to a typical wood frame structure. The in-situ thermal resistance was compared with the nominal thermal resistance and found to differ by up to 14.4%. Three-dimensional thermal modelling determined a range (-4.2% to -24.4%) of potential RSI reductions caused by metal-screw fasteners. In-situ measurements and calibrated one-dimensional WUFI-Pro models determined that the enclosure is not at risk of moisture damage in Toronto and other cold climates. A parametric analysis identified several climatic and materialistic variables that had an influence on the hygrothermal performance of the enclosure. The combined use of collected in-situ data and calibrated modelling allowed for a comprehensive hygrothermal analysis of the proposed enclosure.