Minnesota new construction basement finishing
jimhar
| Posted in General Questions on
Hello,
I have recently moved into new home (built late 2021) in Minneapolis area with a walkout basement. Looking to finish the basement.
I have attached a drawing showing proposed wall section.
My questions are:
I have seen/heard some statements that you cannot insulate on interior if you already have exterior insulation. Is this true in Minnesota? Is this because it would trap moisture?
Would it be best to add space between XPS foam and foundation wall? This question assumes interior insulation is OK.
Is it OK to leave off vapor barrier film between stud wall and drywall? At least for the foundation wall portion of basement.
Thanks,
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Replies
jimhar,
- You are fine adding interior insulation. Concrete doesn't care whether it is wet or not, and in any case the exterior mineral wool allows moisture to move through it.
- No. One of the functions of the foam is to keep moist indoor air from getting to the colder concrete and condensing. A space may make this more difficult to achieve.
- Yes, the foam acts as an air/vapour barrier. You don't need another one.
- Unless you particularly want a wood shelf for some reason, you may want to consider running the interior studs up the whole way to the ceiling. It makes for easier transitions at interior partitions, allows for more insulation in the upper portion, and makes the rooms look less like they are in a basement.