double walls!!! is it ok to connect them at the joists???

hello - i'm kind of new here and havin a slightly hard time getting replies- but i guess my answers are hidden in this forum somewhere-- anywayz if anyone can help me with this i'd greatly appreciate it-- i've looked through the forum and i've even been reading ROD's book-- which is probably the best 30$ i've spent in a long time but i can't figure out how to support the double walls-- i'm guessing that connecting the 2 walls at the ceiling and floor joists will give a path for vibration (impact noise) and with my setup i'm not able to connect the framing to the existing ceiling - i also can't figure out how to construct the floor for impact noise absorption--- i've probably read it over a million times but i just dont get it-- can someone please explain it to me like i'm still in grade school- i'd greatly appreciate it-- heres a diagram of projected studio setup its not great but i'll update it with the actual existing walls soon

Hai, here's a reply :P When building a 4 piece wall (wall's on each side) it'll hold itself in place. Placing just one wall in an existing space is something different. Altho probably exactly the same. Also adding a false ceiling on top of the new walls will strengthen the new walls. Something you just gotta work with what ya gat. I'd add the new wall to the exising (inner?) walls. Adhesing the bottom and top of the wall (floor/ceiling) depends on your existing (inner) walls. Are they connected to floor/ceiling? Then ye'r already "screwed", so attatching the new wall to floor/ceiling will be an option. (hmm fuzzy... )

thanx 4 the reply the design in the pic is a floating room-- the existing walls cannot be altered in any way -- the actual room dimensions are 17'x 50'-- so the double wall studio you see has to be built inside this space- the room has a 12' existing ceiling with a drop ceiling that hangs to about 7' --- there are vent ducts and some electrical wiring above the drop ceiling so basically i was wondering should i use joists across the entire studio ceiling covering the double walls? or if not can i leave the outer wall free standing ? if the airspace isnt closed off somehow wouldnt that defeat the purpose?

Hey kal... It's not clear if you have people either below you or above you. If you have people below, you'll want floor isolation. If you have people above you'll want ceiling isolation. If you want a ceiling that spans your 17 feet, I would suggest 9-1/2" TJI210 I-joists at 24"o.c. They'll carry at least 35 psf... enough for your ceiling. (Assume 10 psf for access live load, pretty conservative.) Before you attach the gypsum board underneath, however, you must attach some 1x4 or 2x4 to the tops of the joists so they don't buckle when loaded. (laid perpendicular across the joists) You can call Weyerhaeuser iLevel for exact spacing but two rows near midspan should do it, seperate the two rows by about 5 feet. For a second floor, it's not too promising... see Rod's book pp. 52-53. However, I imagine some type of cushioning would help a little. Perhaps a layer of special vinyl or Enkasonic. Good luck. Creatch

hi kalajdame - one more obvious thing... if you span your ceiling, and it's isolated from the existing ceiling above, it is okay to attach to your new inner walls but not okay to attach or touch the outer existing walls.

well there is an empty night club beneath me-- it hasn't been rented out yet-- but i'd like to be prepared for when it is rented out. as for the ceiling - there isnt any thing above me- it is only a single floor property - but the ceiling of my studio will not touch the existing ceiling at all - mainly because of the duct work and wiring - i'd have to remove it all to put in a ceiling that reaches the highest point of the room-- i plan on putting in a ceiling that supports my inner walls but reaches below the existing ceiling enough to let the existing ductwork and wiring lay on top of it-- i'm still not sure how to support the outer walls tho- the outer walls wont touch the existing walls at all-- i did a little research on sway bars but im not sure if i can fit them into the budget- also how would i close up the airspace between the outer and inner walls at the ceiling? could i use neoprene pads?-- or a closed cell foam stretched across the ceiling of both walls and glued down?