Simple Question on Frames...

[camistan]

I have looked at numerous frame assemblies for different studios on here. It seems that most "inner-inside" frames are put up after the inner drywall has been installed (ie. framing a soffit assembly for speakers, securing a Helmhotz Resonator assembly etc). With this being the case, what do you SECURE the top of the frame to? It's hard to imagine a heavy frame (especially one to hold a soffit speaker assembly AND the speakers) being secured into RC! Are the frames secured through the drywall to the ceiling joist?

Maybe I am underestimating the strength of RC...

[derekdun101]

toggle bolts attached through the layers of drywall. Best if u dont hit the resilient channel I would think.

[SonicClang]

The only thing attached to the RC should be the drywall, it's not structural. How much construction experience do you have? I'm not quite sure I understood your question. Are you asking about keeping walls decoupled from the joists? I was able to build a lot of my walls sort of free standing from the joists, and when the walls are all connected together they give each other regidity.

Or am I way off?

[camistan]

I mean something like the picture below...

This is a soffit frame for speakers. The top of the frame is right up against the ceiling drywall. This is a ceiling that has 2 layers of drywall that is supported on RC.

Somehow, it's got to be secured to something in the walls and/or ceiling, but what is it secured to???

The only other possibility I can see is it's secured to the wall frame behind it. Even if it is, I've seen construction done where the ceilings AND walls have been drywalled, but another frame is constructed INSIDE the "finished" room drywall to support something else (ie. Full corner traps from ceiling to floor, Helmholtz Resonator walls from ceilings to floor etc). If the idea is NOT to put holes in the walls or ceiling, what do you do in cases like I've mentioned? And furthermore, what about securing things like floor wall trim, ceiling trim, sconce lights or other items to the walls/ceilings?

I'm not a carpenter by trade, but I know some basics. Maybe I'm making more out of this than I should, and yea, I know, common sense dictates that you HAVE to go through the ceiling OR wall drywall to support a frame in the joists/studs. But... when it comes to losing db's of sound isolation because of sound leakage through holes put in drywall for various reasons (even though it's filled with caulk), there may be a better way other than the "standard" way of thinking and constructing to secure a frame or other items to walls/ceilings (for a STUDIO). Maybe you simply "have to do what you have to do" which may result into losing some db of sound isolation.

I simply want to build this thing as best as possible...as SOUNDPROOFED as I can within my means...

Then again, as I said above...maybe I'm underestimating the strength of supporting it in RC...

[camistan]

Ok, I'm gonna partially answer a couple of my questions...
http://www.johnlsayers.com/phpBB2/viewtopic.php?t=5435

And a post I wrote a while back...
http://www.johnlsayers.com/phpBB2/viewtopic.php?t=4890

If securing the frame to the stud/joist is not an option, the only thing left is RC (for the ceiling in my situation)...If this is the case, I would assume an extra strip of RC will have to be located in the ceiling area right where the frame will be secured (That is unless the frame just happened to fall right under a regular-running RC strip)... And if it does, you better be SURE where your screws are located for each previous layer of drywall so you don't run your new "frame screws" into the drywall screws.

As far as a "heavy" cloud or another similar item, I would assume the same holds true for locating a RC strip to support that item unless it also falls right under a regular-running RC strip.

I gotta tell ya...all that weight on that RC strip...

We're not only talking about the weight of drywall hanging from the RC, but now (in the case of a soffit wall) the weight of a frame with speakers, insulation, wood slats etc etc. Maybe by it being in the vertical position there would be hardly any weight pulling "down" on the RC, but possibly some pulling it to one side or another.

Set me straight if the RC way is correct, if there's another solution, or if my flight is headed tward's Pluto....

[knightfly]

Stan, you keep mentioning RC, but it looks as if most of your plan has double walls - can you do a sketch showing where each leaf of mass is located in your plan, so I can see what's what?

As to soffits and support, ideally they could just float in space, attached to nothing. Realistically, not gonna happen...

With a 3-sided front soffit construct, the center "wing" will keep the inner ends of the two outer wings in place so they can free-stand, just fastened to the floor. The outer ends of the left and right wings will need support - probably the simplest way to do this is to use some RSIC-04 hangers - screw a short piece of hat channel thru the wallboard and into the RC, if that's what you're using (still need to see a wall detail), then clip the RSIC onto the hat channel, and screw the "tail" of the RSIC to your soffit frame.

This will give a resilient mount between soffit and wall, and because both are at or near vertical there won't be much in the way of pull - it's more just a non-contact way to "locate" that end of the soffit at its top.

Now, the pedestals your SPEAKERS set on will need to be decoupled from structure, or else you'll get early "reflections" thru the floor, console, and to your ears because this SOLID path will conduct sound nearly three TIMES as soon as the AIR path, and you'll get "pre-echoes", kinda like the ones you get when you wind tape heads out instead of tails out...

Front soffits will act as a third leaf (not sealed, so should NOT be your second leaf) - because of this, it's a good idea to add more layers to your outer two leaves to help compensate for the loss in low frequency isolation of that third leaf.

HTH... Steve

[rod gervais]

Stan,

I (for one) will not run a ceiling through a pair of walls - it always stops to maintain the ceiling within each room - isolated from the other ceilings.

If the ceiling runs through - and then you pin a wall beneath it - you just lost the value of the RC you're using for the ceiling.

You can install resilient channel that only provides lateral support to the wall - and then a seperate channel inside the wall to support the ceiling.

once one wall is adequately supported - items like WIC clips from Mason Industries are perfect to stabilize neighboring walls -

I also love these to use when building walls adjacent to concrete walls in basements.

Rod