Crawl Space Vapor Question
I’m currently rehabbing an older property and I have some questions about the crawl space that the place came with. I had to tear out all the existing floor joists because they rotted, likely due to batt insulation placed in the cavities.
I have the new floor almost finished and have put 10mil poly on the dirt floor beneath it. I would like to insulate the new joists to R30, but I’m worried that there will still be too much water vapor and it may condense on the bottom of the joists. The foundation is made of soft brick and is quite porous – I fixed the bulk water issues the house originally had, but I’m still cautious that water is entering the building from the brick.
I can vent the foundation to the outside if need be. I plan on using mineral wool insulation. One potential fix I thought of was to insulate and cover the bottom of the assembly completely with spray foam. I’m open to other thoughts. The property is located in climate zone 6A.
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