Condensation on concrete floor
I am in the first winter in our small newly built cabin. The cabin has a polished concrete floor that has 3″ of insulation under the slab but on the front elevation has no insulation on the vertical portion of the slab as there is a ledger board that a deck hangs off (I was concerned about compressing the insulation).
In retrospect I regret this detail, as I am now getting a significant enough thermal bridge to develop condensation on the baseboard and concrete floor. At least I think that is what is happening.
This is only in a location that a curtain normally covers, all other areas are fine. So I am thinking that the curtain is trapping the moist air and it isn’t warming sufficiently to dry out resulting in the beginnings of some mold growth on the baseboard and edge of concrete. In addition, this is adjacent to the aluminium sliding patio doors that no doubt leak some cold air.
I cannot move the curtains as there is a wood stove that the curtains should not be too close to. However, this area is never seen because of the curtains therefore I am wondering if it would make sense to adhere a 1″ or so thick layer of rigid foam insulation say 6-8″ into the room directly on the slab (Blue outline on photo)?
Would that prevent this cold surfaces from forming condensation at least right in the corner?
If so, I have some foiled faced polyiso which I could use. Or should I use a more vapour open option (EPS for example) to facilitate drying of the baseboard?
Thank you in advance for your thoughts.
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