isolation question...

I'm sorry if this has been covered before, I did a bit of a search and could not find what i am looking for so hopefully someone can answer my question.. looking at the diagram below between room A and B making the dividing wall with 3 layers per leaf instead of two does this give greater isolation between the two rooms instead of a double layer as per the outer wall? or are the double layer outer walls the "weakest link"? thanx Nick..

Nick, I'm not sure that there would be any real noticeable difference between 3 layers and 2 layers seeing as you don't have separate framing for any of the walls. You may reduce low end transmission somewhat b/w the rooms with a 3rd layer but because your framing is all staggered (not separate), I'm not sure that the gain in performance would be worth the trouble. I'd also hold off on making any choices until you get some more opinions. I hope this helps a little bit. C. Yeazel

What's the situation with the ceilings? Ceilings are among the many things that will make or break your isolation.

for the ceilings I was thinking fluffy insulation>2layers of gyprock> then cloth covered semirigid. I'm building a simple 2 room studio (live & control) http://www.johnlsayers.com/phpBB2/viewtopic.php?t=4356 I will be recording live drums, and need a large amount of isolation between the 2 rooms. do you blokes have any suggestions? thanx Nick.. :?:

Well, since your framing is staggered (not separate or decoupled), you are kind of limited as to the amount of isolation you can achieve between rooms. I think the best thing to do would be as much more mass (layers) as you can afford to all the walls to help get better isolation. If you want to isolate drums from the other room, then more mass is probably the best way to go in your situation. Keep the number of layers throughout the room consistent too.

thanx fella's....

Figuring 1/2" gypsum (you didn't specify) and 2x6 plate/cap, 2x4 stud staggered stud, a "perfect construction) would yield about STC 55 with 28 dB TL @ 50 hZ; adding a third layer on BOTH sides would raise this by 3 dB at all frequencies and lower the msm from 54 hZ to 44 hZ. That's in a PERFECT world; however, it's likely your non-isolated construction's FLANKING will make a third layer almost un-noticeable... Steve

I will be recording mainly rock bands, which in most cases the drums will be very loud. and want to achieve good isolation between the control room and live room so i can hear what is actually coming out of the monitor and not be tainted with sound coming from the live room. but the studio is being built in the country and I dont have a high demand for sound isolation except what I stated before. I have my plan posted in the design forum, I was thinking of floating the control room, and sharwood suggested isolated concrete slabs I am still reading up on these, does anyone have a simpler method?

Hi shmackdaddy, Where in Qld are you? I am in Brisbane. Andrew

mate, I'm in the darling downs area about 20 minutes brisbane side of warwick, if you know were that is? its a bit over an hour to brissy from here, nice to see some fello aussie's so close! are you building or have built?

ok, ive read up on isolated slabs, I dont think you can get much simpler... :oops: I think i will go with the iso slabs and double wall construction with 2 layers 16mm each leaf, i think this will be enough for my needs thanks for your help fella's.. :)

That seems like a winner plan... Post some detailed drawings when you're at that stage! 8)