Zone 5a, Indianapolis
Single story ranch with slab on grade.
4 inch exterior walls
North facing exterior is stone (no weep holes) then 1/2 space then particle board then 2×4 framing with unfaced fiberglass batt then moisture shield ( guessing 3-4 mill regular clear plastic) then 1/2 in dry wall.
All other exterior walls are vinyl siding then particle board then 2×4 framing with unfaced fiberglass batting then moisture shield ( guessing 3-4 mill plastic) then 1/2 in dry wall.
Problems: all the walls are very cold in the winter. Also lots of moisture collects in the walls and does not dry easily to the outside because of the high humidity in the summer. Lastly, there were mold pockets but surprisingly only where there were previous roof leaks.
Because of other renovations, I will be able to strip the walls back to the studs. In the spring I will be redoing the exterior so will be able to remove all (siding and particle board if necessary. Also, renovations are happening in the attic so I will have unrestricted access to the wall and sofits.
First I would like suggestions on the best way to rebuild the exterior walls. I am open to anything.
I would an interested in a spray foam on the outside of the wall with possibly pearlite or no insulation or hydronic heating in the bottom half of the wall or a combination of the those in the wall cavity. Additionally, I would like to put rain screens on the walls and have the bathroom fans vented to the outside wall behind the rain screen.
Is any of that inadvisable? Is there an less expensive way to solve my the cold and condensate problems?
Thanks for considering
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