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What is the best flooring for pier and beam with plywood subfloor?

BHons | Posted in General Questions on

I have a house on pier and beam with a plywood subfloor. The cavities between floor joists are filled with about 4-5 inches of open cell foam. I live about 50 miles southeast of San Antonio, TX. I need suggestions for flooring that will allow inward drying of the subfloor. Thank you in advance for you help/suggestions.

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  1. GBA Editor
    Martin Holladay | | #1

    If I were you, I would install a continuous layer of foil-faced polyiso on the underside of the floor joists, to reduce inward vapor drive during hot, humid weather.

    Softwood flooring like pine, or hardwood flooring like oak or maple, are vapor-permeable. So is unglazed ceramic tile.

    That said, I'm not convinced that you have to worry about the vapor permeance of your flooring -- especially if you take my advice about the foil-faced polyiso.

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