Mold & termite/wood rot in 1920’s house
Climate zone 4A. Hot and humid in the summer and cold in the winter.
The house itself was built in 1920, on top of a rubble foundation built sometime in the 1800’s as a barn.
We removed baseboards and drywall on one full wall of the house and discovered what looks like either severe wood rot or termite damage. The back of the drywall had a sprinkling of black dots but not too bad. Not sure if it was mold or dirt.
The opposite wall, which we started to remove yesterday, doesn’t seem to have the bad wood rot/termite damage to the studs and beams, but it does have pretty significant mold. Additionally, the drywall seemed pretty moist in places.
After we finish removing all the drywall, (somehow) get the mold cleaned up, address whatever is causing the moisture, and replace the all rotted beams and studs –
How to proceed with insulation/vapor barrier to prevent this happening again?
The walls are 1) drywall, 2) cavity, 3) exterior wood (like shiplap but much wider), 4) cedar shingles.
Will a vapor barrier make things worse, or better? I read that insulation on the exterior is ideal but we can’t afford to remove the cedar shingles to access the exterior wall. Unless we do it carefully, save them, and then reattach?
A very few bays had pink fiberglass insulation, which of course was black and moldy. Is rigid foam between the drywall and exterior wall ok or will that cause mold too?
Want to avoid spray foam bc of toxicity.
Thank you so much!
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