Insulating Walls Without Sheathing
Hello everyone. I have an insulation challenge that I could use guidance on. I am located in the Midwest zone 6 and converting a 22’x25′ 1950 detached garage with a concrete floor into a heated workshop.
The exterior is ship lapped redwood siding nailed directly onto the studs that are 16″ on center 2×4’s. There is NO sheathing. Black roofing felt was applied between the studs and siding but what is left is hanging in shreds. Although the siding is in very good shape with no rot it is possible to see daylight thru some of the lower siding boards. I’m certain that a small amount of rain does seep in because of visible water stains. The interior of the siding has never been painted.
The ceiling is 16″ on center 2×6’s with a newly shingled roof that has a ridge vent and soffit vents. I plan to maintain the open cathedral area as it is only 4′ above the rafters.
I will not keep the workshop heated continually yet plan to use electrical heat and a winter working temp of 60 degrees would be optimal. Finished surfaces will probably be drywall.
I am unsure as to how to continue in regards to insulating. I have already applied new 2×2’s to the interior studs to gain depth for thicker insulation. Vapor barrier, airflow, type of insulation and stack-up are a mystery.
My question is how do I properly insulate from the inside and prevent a mold or rot issue?
I thank you in advance as I await your reply.
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