|This three-storey, 15-unit, 1,300 square metre (13,993 sq. ft) walk-up was built in 1958. In the 1980s, the building started showing symptoms of moisture damage. The symptoms appeared after the owners replaced the heating system boiler, installed a combustion air inlet in the boiler room, installed a new roof, sealed some air leakage and changed crawl space ventilation.
Contractors asked for solutions to the moisture problems provided conflicting recommendations, some quite costly. The owners hired an impartial consultant to determine the source of the problems and recommend solutions.
The consultant concluded that poor site and crawl space drainage allowed large quantities of moisture to enter the crawl space. The moisture from the crawl space caused high humidity in the apartments. In cold weather, the high humidity cased deterioration of the building envelope, poor air quality and mold growth on walls.
The consultant recommended grading the crawl space, installing sump pits and sump pumps in the crawl space, landscaping the site to drain surface water away from the building and installing exhaust fans in the crawl space.
The project cost $13,910, plus GST. Moisture and mold problems have ceased.