Keep the basement as finished or convert to unfinished?
We own a house build in 1976. There is musty smell in the basement/basement feels dump during summer. The house is located in Central Massachusetts (Zone 6). The basement has been finished at least 30 years ago, or perhaps was always finished – since the house was build. There is a utility room, full bathroom and sauna there. Unfortunately, it’s wooden framing directly against the concrete, no gasket at the bottom of the basement floor, stud bays are filled with fiberglass. I have removed the carpet and padding from the floor, but I am worried about mold growth in the walls and the quality of the air in the basement/house – the house is located near wetlands. The basement slab is not insulated, there is a sump pump that works during heavy rains. There is some efflorescence on the foundation walls (sections that are visible).
I plan on leaving the floor as unfinished concrete. In terms of walls, I am considering the following options:
1) Remove existing walls, insulate the basement according to best practices (closed cell foam/XPS against the foundation + steal studs framing).
2) Convert the space to unfinished basement.
I am leading towards 1), but I am worried about the lack of gasket between the seal plate and the foundation. There are a few locations around the house where the foundation is exposed only 6 – 10 inches above the ground. Is there any way to mitigate this risk?
Am I making a mistake trying to keep this space as “finished”? Another option would be to start running dehumidifier in summer and heat the space in winter (baseboard heaters are installed in the basement), but’s not solving the root cause of the problem.
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