CQL was recently asked by the Gwiich’in Development Council (GDC) to provide an Engineer’s Report outlining the cause and possible remediation options for a building experiencing moisture infiltration. Condensation in roof assemblies is a common problem in buildings in the north due to the cold dry arctic air contrasting the heat of an occupied space. An extensive analysis as to why condensation is occurring in the building’s roof assembly was conducted and a roof assembly design was proposed to not only mitigate the current problem but eliminate it from reoccurring.
There appears no easy fix to the moisture infiltration occurring at the Norcan Building. The water/moisture infiltration is attributed to two main factors, namely discontinuities in the 6mm poly vapour barrier (more accurately termed vapour retarder), and the lack of a ventilated roof/ceiling. The proposed solution has considered the accessibility to the ceiling, the need to limit disruption of tenants and the construction sequence in placing a new vapour barrier in an existing building. The solution is further affected by the possibility of mold in the ceiling, this could not be confirmed (as no testing was conducted), but the high moisture content, included wet 5/8” OSB roof sheathing, makes for a high mold probability. Immediate testing for levels of potential mold spores should be conducted.
