Durability and Disaster Mitigation in Wood Frame Housing

The main objective of this paper is to highlight the research works being carried out on the hygrothermal behaviour of building materials and wall systems at the National Research Council (NRC) Canada. The paper depicts selected results obtained from parametric studies conducted on wood frame stucco walls commonly used in Canadian climatic conditions, using hygIRC, an advanced hygrothermal modelling tool developed over the years at the Institute for Research in Construction (IRC), NRC Canada. The assumed wall configurations, environmental conditions and material properties used in the study and the rationale behind such assumptions are highlighted. The drying potential of the composite wall systems and drying characteristics of various individual wall components are analysed. A number of parameters which influence the moisture movement to and from the wall have been selected for this study and they are : (1) Presence of ventilation cavity behind the cladding, (2) Size of the vent cavity, (3) Variation of external relative humidity (RH), and (4) Solar radiation on the exterior face of the wall. The parametric studies, based on simulation results, call upon the urgent need to verify these observations by conducting closely monitored field tests.