To vapor barrier or not to vapor barrier?
Pardon my ignorance or lack of proper nomenclature, but have a question regarding vapor barrier/retarder (I know they are not one and the same) and insulation.
We live in NH. We have an office/den that was an addition built over a very shallow crawl space. Two of the walls are exterior. We ripped up the floor, joists, etc, and, in doing so, had to remove some interior tongue & groove paneling that runs horizontally about 3.5′ up from the floor. Above that, the walls are covered in drywall, which we’re leaving. We cut the existing faced fiberglass about 3′ up between the studs to get at the electrical and run new wiring, etc. We’re ready to put new insulation where we removed it and are planning to use unfaced Roxul, but my question is whether or not to put up any vapor barrier/retarder on top of the insulation along the (2) exterior walls. Our plan is to put shiplap over it. Externally, there is siding, and I can’t tell if they used a housewrap or not. There is certainly not any exterior insulation.
The room is heated somewhat in the winter, but not air conditioned in the summer, if that helps. Grappling with whether or not to put anything on the interior of the new insulation before we put on the shiplap.
Appreciate any insights!
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