Soundproofing ceiling between apartments: plaster or drywall?

We are gutting an apartment and are considering adding soundproofing between us and the neighbors above.
Currently there is the original plaster and wood lathe and a layer of drywall stuck to it with no insulation between the joists.
We are considering taking all of that down to the bare joists, adding something like Roxul Safe and Sound to insulate for sound and putting back a layer of drywall.

Any thoughts on which will work better?
I’ve heard mixed things on the sound reduction value of plaster.
And right now I’m not looking to take into account the other advantages of plaster or the mess involved with removing plaster- I’m just trying to focus on sound reduction.
Anyone done this type of work before?
I know there are other things we can add like de-coupling the ceiling, but for this situation our options are:

Sound-insulated drywall or non-insulated plaster and lathe?

brooklynmaterials

in General Discussion 8 years and 5 months ago

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joearchitect | 8 years and 5 months ago

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If you remove the existing ceiling then install Roxul and a new ceiling attached to the joists it is not likely to be any quieter than what you have now. That is because the the most noticeable noise from above is likely to be impact noises – footsteps, toddler dropping things on the floor, etc. Those noises are transmitted through the joists directly to your ceiling. At the least, the new ceiling should be screwed to resilient channels, not directly to the joists. A better solution would be to install new ceiling framing between the existing joists but not touching them. That would also allow you level the ceiling. Install the Roxul to muffle airborn sounds like music and yelling, etc. More mass (thickness) for the ceiling can help, but the required 5/8″ type x should be adequate. Try to avoid recessed lights in the ceiling as these will leak sound.

brooklynmaterials | 8 years and 5 months ago

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Oh and just to be clear the Roxul insulation is like batts that are pushed in to fill the space between the joists.