Sustainable building practices are rooted in the need for reliable information on the long-term performance of building materials; specifically, the expected service-life of building materials, components, and assemblies. This need is ever more evident given the anticipated effects of climate change on the built environment and the many governmental initiatives world-wide focused on ensuring that structures are not only resilient at their inception but also, can maintain their resilience over the long-term. The Government of Canada has funded an initiative now being completed at the National Research Council of Canada’s (NRC) Construction Research Centre on “Climate Resilience of Buildings and Core Public infrastructure”. The outcomes from this work will help permit integrating climate resilience of buildings into guides and codes for practitioners of building and infrastructure design. In this paper, the impacts of climate change on buildings are discussed and a review of studies on the durability of building envelope materials and elements is provided in consideration of the expected effects of climate change on the longevity and resilience of such products over time. Projected changes in key climate variables affecting the durability of building materials is presented such that specifications for the selection of products given climate change effects can be offered. Implications in regard to the maintainability of buildings when considering the potential effects of climate change on the durability of buildings and its components is also discussed.

The long-term performance in respect to moisture management within any wood frame wall assembly depends on the hygrothermal response of the wall to local climate moisture loads. Estimating the wood moisture content, temperature and time of exposure to conditions suitable for the onset, growth and propagation of mold or rot are critical parameters when assessing the longevity of wood frame structures. A number of approaches to assessing the vulnerability of wood frame structures to deterioration have been developed in recent years one of which has been used by NRC-Construction for evaluating the performance of wall assemblies based on the results from hygrothermal simulation. In this paper, an example of the use of this approach for the assessment of a stucco-clad wall incorporating drainage cavities is described as is the use of a Mould index to capture the risk to the formation of mould in walls. An example is given in assessing the moisture management of a stucco-clad wood frame wall incorporating vented and ventilated drainage cavities for three Canadian locations.

This paper presents the results of a Guarded Hot Box (GHB) experiment on a wall assembly made up of both steel stud framing and an external insulating assembly which incorporates vacuum insulation panels (VIPs) for which knowledge of the composition of the VIP barrier foil is not readily available. The purpose of the tests is to provide an experiment result for thermal resistance of a wall assembly containing several sources of thermal bridging, including those due to the barrier foil at the edge of and joint material between the VIPs and the condensation potential on the interior surface due to the steel studs. The steady-state GHB experiments were completed in accordance with ASTM C1363 for an interior air temperature of 20.9°C and an exterior air temperature of −34.9°C; this resulted in a thermal resistance for the wall assembly of 6.8 ± 0.8 m2 K/W. Surface temperature measurements on a VIP in the wall assembly indicated that increased levels of heat transfer were occurring at the edges of the VIPs as compared to the center of the panel confirming thermal bridges were present at the panel edge. Measurement of the temperature on the interior surface of the sheathing board around the steel stud indicated that the external insulation effectively minimized the risk of condensation due to the steel studs. Determining the thermal resistance and condensation risk for a wall assembly which contains VIPs for which knowledge of the barrier film is not readily available demonstrates the potential for use of such a wall assembly according to energy and building code requirements. The wall assembly and test details can also be used to compare industry standard calculation methods and detailed 2D and 3D simulations to the GHB test result. The comparison can be used to inform on the validity of using calculations and simulation methods in lieu of testing for energy and building code compliance. The comparison of calculations and simulations is not the scope of the work presented in this paper and will be explored in future publications.

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