Insulation on existing wood floors above a crawlspace
Hello. I am turning a home into a duplex in northern PA, zone 5, that is built on a 1′ crawlspace. The crawlspace walls are uneven hand-laid stone. The soil after lots of rain is damp, but no standing water. The joists have no rot and are dry to the touch. It is an old grange, so it is currently an empty shell of a late 1800’s built home (no heating, plumbing, electric, insulation.) The floors are original wood floors in good shape, but I will be covering them with laminate as renters are rough on things.
I have read through every article I can find on how I should handle the crawlspace and floor insulation. I’ve learned turning it into a conditioned crawlspace is the far and away best choice, but the costs and difficulties of tearing up the existing wood floor and subfloor, putting a vapor barrier on the ground, and paying for foam on all the walls is hard to justify.
I have nearly settled on the following:
1) Lay (possibly glue it) 2″ (considering 1″) of XPS, staggering seams, on all of the existing wood floor and tape all seams.
2) Lay 3/4 “t&g and screw down into original plywood on top of joists.
3) Install laminate
Can anyone offer a final opinion on if I may encounter any moisture issues that the house has never experienced in the past 140 years by heating it and putting insulation on top of the existing floors? Are there any other items with this plan that I’m not thinking of? Most discussions on this topic apply to slabs, so I’m mostly questioning moisture.
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