So an architect is in process of finalizing my drawings for a 1st floor 3 Room addition, and I am at the point were I need to make some final decisions. So I turn to the experts for a bit of advice.
Theater room is 27x15x10 (half of the addition)
Floor is concrete slab (all three rooms will be on separate slab than rest of house). There is nothing above the addition other than attic space. This attic space will be separated from the rest of house attic space by concrete block - some minor punch through for electrical, etc. The two rooms adjacent to the theater will be a game room and an office (not true "living" space)
1) Back Wall - Concrete block - 1 inch air gap - standard 2x4 frame
2) Front Wall - Concrete block - 1 inch air gap - standard 2x4 frame
3) Side Wall - Concrete Block - 1 inch air gap - standard 2x4 frame
4) Side wall (separating theater from 2 other rooms) - 2x4 Staggered stud (2x6 sole plate)
I will do double drywall (5/8) with 2 tubes green glue on all walls.
Question) Is double drywall on ceiling necessary? I assume yes.
Walls and ceiling will be drywalled before soffits are constructed. A/C will most likely be housed in soffits, or come in through ceiling. I still need to determine best way to do this, since room will need a return (advice accepted
Question) Even though staggered stud is decoupled, it is really still connected by sole plate, and also the door jamb. Anything else that needs to be done regarding the staggered stud?
Question) Is it necessary to put anything between framing and floor, or just anchor to bare concrete?
Although I know this question is subjective, is this "good enough?" Or are there additional things that will be NECESSARY to isolation?, i.e. What else is truly ESSENTIAL for isloation?
Basically I don't want to be that guy that everyone says "Can you believe that chump did DD/GG, Air Gap, Staggered Stud, etc, but he didn't bother to do XYZ, which truly negates what he DID do... and it wouldn't have been that difficult to do XYZ!
But then again I dont want increase my costs and effort 20% for something that will only increase isolation performance by 2%.
Thanks for all the help, I'm looking forward to your responses.