Experimental Evaluation of Thermal Response and Condensation Performance of Metal Curtain Walls Subjected to Air Leakage

Abstract

The condensation resistance of fenestration products is typically determined in standard tests with air leakage eliminated by sealing the cracks and balancing the pressure difference across the test specimen. In reality, however, the fenestration system does experience varying pressure differentials. The infiltration and exfiltration of air can affect the temperature distribution on the fenestration system and, thus, the condensation resistance. In this paper the effect of air leakage on the condensation resistance of a large-scale metal curtain wall subjected to a pressure differential of 150 Pa is studied experimentally. By examining the temperature response profiles and the magnitudes of the temperature variations, likely air leakage paths are identified and the impact of air leakage on condensation resistance is quantified. Since the airtightness of the curtain wall tested is relatively high, the effect of air infiltration is relatively small on the average condensation resistance but is significant locally.