What humidity levels are risky in unvented/poorly vented attics? What are signs of problems & how to fix?

What levels of humidity (or dewpoint, VPD, etc) are risky in an unvented or poorly vented attic in zone 4A, and how would we know if there are problems (rot,… What levels of humidity (or dewpoint, VPD, etc) are risky in an unvented or poorly vented attic in zone 4A, and how would we know if there are problems (rot,…Read MoreGreenBuildingAdvisor