I have a space that I am considering using for a secondary listening area and I would like to reduce the acoustic transmissions both into and out-of the room.
The room is an unused bedroom approximately 10' x 12' with a single door for access. I'm swapping out the existing hollow-core door with a solid-core version and will be adding an extra layer of 5/8" drywall to the walls. The ceiling in this room is existing 1/2" drywall covered with spray "popcorn". I've already had this tested as being asbestos free but I still loathe the idea of removing it. Instead, I've read that I can install firring strips and then layer on a second layer of drywall, sandwiching the popcorn in and avoiding the godawful mess. This would be of double benefit as I would likely see reduced sound transmission.
My question is, how can I determine whether adding the second layer of drywall to the ceiling will result in a safe static load? There are no living spaces above and the beams are 24" OC, solid no-knot pine. I want to make sure that anything I add doesn't bring the whole thing down on my head!