Plain old fiberglass might not be nearly as good as rock wool in that perception. I would take the Roxul men suggestions and put in flush to subfloor, the joists could even be tall enough for a second layer of batts. Insulation performs a vital position in thermal performance. It https://tiling-a-bathroom91356.bloggip.com/34733477/how-much-you-need-to-expect-you-ll-pay-for-a-good-thermal-performance