Smell from first floor after finishing basement
Hope to get an assist with my smell situation.
I’m in Toronto, Canada and I have a bungalow from the 1950s. Last autumn we finished the basement, including exterior waterproofing, rubberized and damp proofing membranes, and spray foaming the interior wood 2×4 walls with closed cell insulation. The foundation wall is concrete block, with a (I think) double brick veneer above ground.
This spring/summer we have had a strong wet/damp/old brick smell coming from the floor/wall of one of NE rooms. I am not getting the smell anywhere else on the first floor. It seems to be strongest when the temperature changes drastically between inside and outside temperature, ie the weather has been cooler the last few days and it’s less noticeable, although I haven’t correlated a specific trigger for the smell.
The basement area under the room is the laundry facility and there is no odour there. I have checked for leaky dryer vent, moisture/leaky water line and no such success. Been in the attic looking for water penetration, also had the water proofer excavate down to the footing to check for water in the block that can’t evaporate and both cases no water. Opened up a piece of wall in the basement corner and scraped out the spray foam and no water, that said the brick and foam were moist to touch.
Based on a previous post and answer by Dana in this thread:
I’m starting to suspect the odour is caused by not have a vapour barrier in the section where the floor/rim joists are ie between spray foam in basement and tarpaper barrier in first floor walls. I am now thinking of spray foaming this area to see if it will resolve the odour. I’ve attached a diagram of the current situation.
Has anyone ever run into a situation like this or have any opinions?
I would appreciate any feedback, I have my original contractor and others out to investigate and no particular help.
PS Updated the diagram to have the veneer on the block!
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