In Situ Thermal Resistance Testing of an Energy Efficient Building Envelope in the Canadian Arctic

A structural insulated panel (SIP) demonstration house was commissioned in Iqaluit, Nunavut, Canada, along with instrumentation to assess thermal performance. Instrumentation panels were developed to perform in situ measurements. Laboratory testing was completed to confirm the accuracy of the instrumentation panels and measure the thermal resistance of the insulation panels at various mean temperatures. In situ testing confirmed the variability in R-value with temperature seen in laboratory testing. The thermal resistance decreases with decreasing temperature, which is of concern in this particularly cold climate. Regardless, the envelope thermal performance was consistently superior to a 2″ × 6″ (38 mm × 89 mm) wood stud construction with batt insulation. The in situ R-value of the SIP varied from approximately RSI 4.4 (R25) to RSI 5.3 (R30) between October, 2016 and April, 2017. The cumulative apparent R-value was also calculated according to the method defined in ISO 9869, resulting in values of RSI 5.07 (R28.8), 4.84 (R27.5), and 4.97 (R28.2) for the wall, floor, and ceiling modules, respectively.