Insulating victorian house walls
I have a house built in 1868. The exterior walls are lapped redwood siding, full dimension 2×4, and then lathe and plaster on the interior. There is no moisture barrier under the siding.
A contractor has proposed renailing (old square nails badly corroded), caulking and painting the siding and then using fiberglass insulation on the wall interior. The lathe and plaster would be replaced with plywood for shear strength, covered by sheet rock.
My concern is that moisture will inevitably get inside the wall and then be soaked up and retained by the insulation, leading to long term wood rot or mildew problems.
Would use of rock wool instead of fiberglass insulation reduce the risk of moisture damage? Is there any other detail I should be asking for to prevent moisture problems in the walls?
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