The acoustic properties of different roxul products depend on their thickness and density.
Roxul safe and sound ceiling installation.
If you are using rockwool safensound suggest you install between the framing members above the suspended ceiling if you have access to them.
Made from non combustible stone wool roxul safe n sound can withstand intense temperatures of up to 2150 f and delays the spread of fire for added safety.
Roxul acoustic insulation sound properties.
Rockwool safe n sound is a stone wool insulation product for use in interior wall partitions floors and ceilings of residential wood and steel stud construction.
Good luck getting the full batt up there cut that sucker.
Safe n sound has a density of 2 5 lb ft an stc sound transmission class of 45 on 16 center wood studs 52 with 24 center steel studs and 50 when used between floor joists.