Structural Support for Ceiling

I won't comment on the structural aspects of your project, but I was wondering what type of isolation you are going to provide. Typically soundproof rooms are built on the room inside a room principle where the drywall and/or the studs to which it is attached, is totally isolated from the rest of the structure by vibration absorbing materials. Relying on fiberglass insulation alone will not stop vibrations in your underlying structure from finding their way into your space, nor will acoustic foam on the interior facing walls and ceiling.

Depending on the isolation wanted,staggered stud construction is recommended.

Lead, not fiberglass stops sound.

It would be a lot lighter with metal studs and acoustiblok®....

http://www.acoustiblok.com/uses.php

The plan is for decoupled walls, with the inner wall of steel framing. Will there be enough holding power to hang two layers of drywall under steel studs? Can you even get them in 16' length (cut down to 13')? Thanks for your replies.

Steel studs are easy to work with and cheap...here are some guides to help...

http://www.familyhandyman.com/carpentry/using-steel-studs/view-all

http://www.wikihow.com/Install-Metal-Studs

video....

https://www.youtube.com/watch?v=amK2edm20ss

If you go with steel studs... do yourself a favor and make sure to use work gloves while working with them. They can slice you up pretty well and surprisingly easy.

All good ideas..We built sound studios and also remodeled existing rooms into sound studios. Structural considerations will have to be dealt with with the weight of the material used..With large sheets of sound dampening products, like specialty drywall with aluminum sheet melded in, to sheet lead with drywall, interspaced with perforated soundboard, built up in layers almost 2 inches thick. For these , a lot of consideration on how to support them will come into play. We cut off all the studs and installed Rubber Iso Blocks holding up 4 X bottom plates, staggered studs on top, and various layers of sheet materials over the studs and used special sound reducing clips for connections to ceilings. This wall system is 3 inches away from the outer structural wall, and filled with acoustical fiber. The whole purpose is to isolate the outer and inner skins so frequencies either cancel each other out, or are isolated totally. Realize that your floor will love those low frequencies, and are very efficient in transferring said frquencies into areas that will drive you nuts--If possible, isolate it also. While doing this, we have a sound engineer, with frequency meters and an oscillicope measuring the result of each layer as it is applied. The last one we did was engineered for Acapella groups, solo singers, and fine solo acoustical instruments, like guitar and violin. Also, the walls were 30 degrees offset, and the ceiling was also tilted down. No square angles or parallel surfaces. Totally different treatment than say, a room for a heavy metal band, or any electronically amplified material, drums and the like. Figure out the purpose first, and all data can be found on line. Good luck!

Thanks so much for all the info! This gives me a lot to think about and research.

Thank you so much SolarEagle for guiding me in the direction of metal framing.

Due to the entire weight of the project I've decided to go with metal framing with a structure similar to this.

The ceiling joists will be 18 guage steel 16" OC with midspan bracing. The span chart shows this structure will easily support the double drywall. Will the walls also need to be 18 gauge? The thicker the metal, the less effective acoustically. I'd like to frame the walls with 25 gauge, if possible. As far as I can tell, this structure doesn't rely on hangers from above structure. This is perfect for me, creating a totally decoupled system. Am I interpreting the diagram correctly?