I am looking for advise on establishing a RH for a wood floor system. (special system from Europe very dimensionally stable)
The flooring has a RH limit of 90% over 6-mil poly that has a perm of 0.06.
I want to put the flooring down over 15-mil poly with a perm of 0.018-0.01. (83% less)
What RH should the concrete be? perhaps 83% of the difference between 90 & 100? So that would be 98% RH? I don't think it is a sliding linear scale though.