Leaky Condos

The ingress of water behind the building envelope has resulted in billions of dollars of repairs over the last 2 decades in Canada, and has generated the term "leaky condo syndrome." Our research on wind-driven rain will lead to improved construction details and help to prevent problems such as this in future.

Applied Research

Climate change is a reality and an urgent matter for mankind to deal with. Buildings consume 40% of energy and contribute to one-third of greenhouse gas emissions. Canadians spend over 90 percent of their time in buildings, which in turn account for 60 percent of its $110 billion construction industry. Human health, the economy, and the environment all suffer when buildings fail, and over 50 percent of building failures are directly linked to the performance of the walls, roofs, and floors of buildings--collectively known as the building envelope. The accumulation of excessive moisture in the building envelope reduces a building's durability and compromises the quality of the indoor environment leading to major repairs and absenteeism of people working in the building. A regional interest in rain penetration has combined with national and international partnerships to centre our initial infrastructure development and research activities on themes related to building envelopes and their durability and energy performance.

Our research will lead to advances in best practice guidelines and building codes and standards, help resolve current and future deficiencies in building design and construction, and improve the overall performance of buildings, thus contribute to sustainable development. This should help to identify and resolve critical weaknesses in the building systems we all depend on before they become part of our homes, schools, and workplaces.

The Building Science Centre of Excellence has designed a comprehensive research program with capacity in three interrelated research aspects:

  • Experimental studies: to better understand and characterize the performance of envelope systems, e.g. wetting and drying processes, under controlled indoor and/or outdoor environmental scenarios.
  • Field monitoring: to assess the actual envelope operating indoor and outdoor environmental conditions to understand and characterize envelope response to these.
  • Computer modeling: to improve the accuracy of performance predictions from a thorough understanding and application of building science principles with models validated through experiments and field monitoring.


Our current research capacity includes evaluation of building envelope performance (i.e. hygrothermal, energy, durability) of materials, components, and building system levels through laboratory and field testing and advanced modeling and computer simulations. We are expanding our research capacity in monitoring and modeling of energy efficiency of buildings; developing specific models in heat transfer and computational fluid dynamics; investigating protocols and models for risk assessment of building envelopes and indoor environmental quality; and establishing a foundation for building life cycle design.