What can I use as an air barrier under an old wood floor with no sub floor?
This is an old house 1860 with 1910 addition. The old wood floors have no subfloor and on first floor, that is above a dirt floor basement. Since we have access to the floor from the basement I want to put up something that will block airflow through the floor. A bit of insulation would be a plus. I think it should also allow moisture to pass through. I would rather put it between the floor joists (> 2" x 10", 2' on center, oak hard as rock) and not cover them up. I have considered homosote. Any suggestions?