Use of Brick Veneer/Steel Stud wall systems has preceded adequate forma} scientific investigation into its long term serviceability and safety. Of particular interest to many parties is the performance of the wall system under typical winter conditions encountered in cold climate regions of Canada. In this study, experimental investigations of three types of Brick Veneer/Steel Stud wall systems were performed using a specially built apparatus used to provide air pressure, temperature and vapour pressure differentials across test specimens.