Drop ceiling - sound insulation

[JohnE]

We plan to lower the ceiling in a living room but for reasons other than sound insulation. Since we will be doing this work anyway, i was wondering if it would be worth to take sound insulation into account also while doing this. 

We live in an older 3 story house circa 1942. It has very thick brick walls, high ceilings, wooden floors. Previous owner dropped the ceiling of the bathroom from 3m to 2.65m (9.8 to 8.7 feet). Simple wooden frame and drywall was used, no decoupling. Since we will be doing this work anyway, i was wondering if it would be worth to do some decoupling and adding batt insulation for sound insulation purposes. 

The room in question has 2 outside walls and 2 walls to other rooms in our apartment. We have an older lady living above us. The only noises we hear are tv and speech (very rarely and very quiet), we hear noises when she is walking since its old wooden floor and when she is opening big wooden drawers. None of the noises are disturbing enough to make us sound insulate the room, its merely a consideration since we are lowering the ceiling anyway. It could become a bigger issue if a family with young children were to move in. 

I have some basic understanding of how sound travels, namely that it travels through the construction, walls, etc. Especially impact sounds are problematic and usualy hard to do much about, usualy the only solutions are either neighbour replacing it's floor and do proper decoupling or building a room in a room. I couldn't find any data on how much does the ceiling alone improve the sound insulation and whether it would be worth adding some batt and do a proper decoupling, maybe adding a second layer of drywall. I don't know what % of sound will just skip the ceiling and travel down the wall. I weight the dB reduction against the added cost and 3dB reduction (~23% reduced perceived noise) is generaly the minimum i would deem worth it. 

Edited October 31, 2023 by JohnE