Green Glue..I know I know.

[sei046]

Hey guys,
If I have two individually studded and individually floored (raised off of the concrete for levelling purposes) rooms in a larger concrete structure and I am not overly concerned about sound isolation between outside and inside but only between the two rooms is it necessary to green glue all the boundaries still?

So for my purposes the studded rooms that are inset from the walls with double drywall and insulation will be plenty of isolation from the outside in my situation. However, I do want reasonable isolation between the two rooms (confidently eq'ing a drum session in the control room within reason). I understand that obviously the sound from a drum kit in the live room is going to be exiting all boundaries and into the environment but would it be reasonable to just green glue the two facing walls between the rooms?

Would the dampening of the vibration on the two facing walls across the say 150-200mm air-gap be effective or is it an all or nothing situation?

ALSO
If we say that the walls are 2.5m in both rooms, is there any addition to me building a concrete wall between the two rooms and leaving a smaller air gap either side of it between the wall and the studs if it is not possible for the concrete wall to finish up to the ceiling. So the wall heights of the rooms and the wall would be the same but as both rooms have a slight A frame roof it would fall short of completely dividing the structures.

I suppose I am also asking if a concrete "partition" would add or take away from the setup or am I actually better off to just go with the double leaf and single larger airgap approach.


Thanks for any help.

[DanDan]

I would go with carefully built doubled plasterboard. I don't think GG is cost effective. Do some pricing of the 'acoustic' plasterboards. One of those here in our country claims a Rw of 40dB vs the 34 of regular board. Every part of a MAM system is important. Seal all the gaps between boards. Do a different pattern for the second layer. The air gap needs to be as big as possible. Fill it carefully with light cheap attic or partition roll. Fully filled, touching the plasterboards lightly but not compressed. You may need to include some string or wire or whatever supports to prevent it from sagging down over time.

[sei046]

Hey Dandan, Everything you said there seems to be the plan so far anyways so thats great to get confirmation for the minute. I can afford a bit of an airgap so even If I had to take it to 500mm I dont mind. And absolutely on the gaps, I would take that as a given. Just wondering if GG on every panel would be neccesary in my scenario

[sei046]

Up the Rebels by they way!
Thanks
D