John Sayers' Recording Studio Design Forum Archive

Hello Steve. I was wondering if a composite panel, comprised of 1 1/2" rigid foam insulation panel, sandwitched(via sprayed on contact cement) between (1 sheet) of 1/2"x4'x8' ply or osb, on one face, and( 1/4" masonite or ply on the other, with a 2x2 fir frame surrounding the perimeter of the insulation panel also sandwitched....(whew) .....would that be considered ONE LEAF? I was wondering if this could be used as a STRUCTUAL ONE LEAF for a Vocal booth enclosure. Thereby eleminating building a seperate wall frame such as a normal wall. Hmmmm...sounds confusing in words and I tried to post a .gif last night but to no avail even though it was only 98k. It would attatch to the post in this screen but would not go through to the server

fitZ

Hey Fitz - to the best of my knowledge, closed cell foam acts as a (poor) solid for acoustic purposes - it doesn't pass air because it's closed cell, and it doesn't have much mass, so it basically sorta sucks...

it would, however, act as a (piss-poor) single leaf with multiple layers as near as I can tell... Steve

Holy cow! I didn't think this thread posted. I began to think I was banned for saying something foolish. Like foam insulation!! Ha! Well, I would have thought the very reason it would work was because of its nature of closed cell, and no air molecules to move from vibration. But what do I know. Well, ok, back to the drawing board. I'm trying to figure a way to make a thin, self framed, rigid, low ST, lightweight and CHEAP Vocal booth wall leaf structure. Hehehehehe!!! Oh, add great absorption charachteristics to that list too!! Hmmmm.....just foolin around anyway. Thanks Steve. BTW, I sure have had trouble posting things. Is there anything I should know
cheers
fitZ

Actually - It don't believe it would be one-leaf at all - it would be a 2 leaf - with foam insulation between the leaves.

If you construct a wall - and use spray foam insulation - and drywall both sides - you still have a 2 leaf wall - the foam has enough movement that regardless of the lack of studs the 2 leaves are still going to have independent reactions to an extent.

I agree with Steve that it won't work.

Rod

Hello Rod, well I didn't really think so either. Just had to have some one confirm my doubts. And please, the laughter is ok, but lets hold it down to a low roar.
fitZ

Hmmmm, I just tried to post another reply, but the bbs, is acting kind of wierd. Anyway, I just thought of something Rod. Can you explain why a three layer composite, such as gypbd, ply, and gyp board, fastened to RC or a stud, is considered one leaf, yet the 3 layers I described, attatched to nothing, is considered a 2 leaf system? Just trying to learn a few things, and as Steve says, nothing wrong with growing a few neuron networks!(I think thats what those braincell wires are called)
fitZ

Neurons be damned, full speed behind...

"yet the 3 layers I described, attatched to nothing, is considered a 2 leaf system?" - Not to me - those would be considered raw materials until they're attached to something.

Seriously, we have a terminology problem between us yanks and the Brits - apparently, the BBC refers to a complete "camden", or a stud wall with wallboard on both sides, as a "leaf" - I, and everyone on this side of the pond that I'm aware of, calls this a "wall", and not a very good one by itself. I need to re-read some of the BBC pdf's to get their terminology straight in my mind again; right now, all I know is it's DIFFERENT... Steve

FitZ,

I firgure that eventually this would have to be attached to a frame in order to hold it in place. The frame would have to be rigid enough to support it.

Thus I liken it to a wall assembly which has the cavity filled with spray foam insulation. Same basic materials - same basic properties.

This is (regardless of the foam) a 2 leaf wall system. I don't see it changing just because you don't have the studs installed between the sheets - but rather at the end.

The foam itself (apparently) does not have enough body and mass to really create a one leaf system.


Once again - this is only my perception - I tend to discount the foam completely.

By the way - the only time i ever laugh is when someone comes to me and says:

"I built this - and THEN I READ THE INFO - oops - what should i do now to fix it - oh by the way - i don't want to take anything apart. Can you help me?"

Oh yeah - i also laugh when people talk about time travel (and don't understand the paradox) and when people talk about renewable energy sources that will not effect the ecosystem. As if energy can somehow be created -

But i never laugh at new ideas - the Wright Brothers flew - we all know that horses never did away with the horseless carriage - and man walked on the moon........ new creative ideas are the best thing since sliced ham.

Rod

Hello Rod, thank you for your interpretation. As a matter of fact, the whole purpose was NOT to fasten to a frame. You don't have to. Just fasten to a floor panel assembly, and a ceiling panel assembly. And float the whole box.
When I worked in a Professional Display shop, the crates we built to ship things were pretty much the same idea. Basically, it DID have a 2x2 frame with one sheet of 1/4" ply. We would build these panels and assemble them into a packing crate box, with the ply facing to the interior. Some of these were quite large, and very strong. For this scenario, I just added an external sheet of ply,, took out the interior framing members, and filled the void with foam. You assemble these as if they are a cabinet with 2" plus or minus, thick panels.
In another senario, I was thinking if you could fill the voids with this new material that they cast architectural millwork copys out of, which is quite a bit heavier, and has no air at all, it will adhere to both sheets of ply, therefore making it ONE SHEET. I WOULD have a perimeter frame of 2x2 inbetween the sandwich, which would be glued to both sheets also. When a manufacturer of these millwork castings pours the compound into a mold, they are in a hydrolic press, that keeps the compound from expanding out of the mold.
If the mold were simply one of these panels, with a hole to inject the compound, and then compressed flat in a large panel hydrolic press, it basically would become one solid panel. At least that is the idea. I've seen it demonstrated in other forms. With pre installed hardware on the frame, like T nuts or whatever is required, to make for easy and quick assembly. The floor would be similar, although thicker, but the ceiling would be the same. Of course, you would have to have modified designs for door and window surround panels, but I think they could be done fairly simply. I DID try and post some drawings but the server or whatever won't let me. As a matter of fact, the design is a pentagon, instead of a square or rectangle. Thereby getting rid of the parallel wall syndrome. 5 wall panels, with a braked metal corner, for attatching the angled corners togeather.
l What I am trying to achieve, is a shell, whereby you assemble a floor, walls, and ceiling from pre assembled PANELS, with no frame, just like a Packing Crate. This would be ONE LEAF. Whether or not this design will work is not the issue. It is the idea of a ONE LEAF FRAMELESS panel system, made of some type of composites that I am trying to come up with, short of prestressed concrete panels The next problem is the outer leaf. In a room within a room system, each room has its own inner leaf, with the outer shell being the exterior leaf, correct. With vocal booths, EITHER, you have to build an enclosure which is one leaf, and then another shell, which is the second leaf, within a room. That is a room, in a shell, in a room, correct. At least to my way of thinking. The problem is the outer or second leaf shell. To me, that is simply the existing floor and ceiling, with new walls, built between the existing floor and ceiling, surrounding the vocal booth inner leaf, which for all intents and purposes, is floated. Does this make sense?
The reason I am trying to figure this out, is to design a prefabricated kit, wherby you order various panels, to make what ever size booth you want. This would ONLY be the interior leaf. That way, anyone who wants one, only has to build the exterior leaf between their own existing floor and ceiling, which everyone knows can be any number of conditions particular to their location. Thats the usual problem with building vocal booths that are NOT an existing room. You have to build a freestanding enclosure that is TWO LEAFS WITHIN a room. Or like I said, a room, within a shell, within a room. That is, IF your not using an EXISTING ROOM to make IT the vocal booth. Hmmmm, is that double talk!

Now, if I could ALSO figure out how to isolate a connection for an external leaf, well.....hmmmm, maybe turning lead into gold would be easier, ha!! Well, thanks for the patience reading my killing time brainfarts Rod. Doggone I wish I could get drawings to post.....I wonder whats wrong? Maybe its just ME.
fitZ

FitZ,

Well - regardless of your idea - one of the things you are going to have to do - in order to produce a product and market it - is to provide the testing to verify the level of isolation.

You could always make some mock-up's of your ideas and then have them tested.

You could try some testing yourself to determine whether the basic concept of your system will work or not - but eventually you have to have it all certified by a reputable lab somewhere.

One of the problems with isolation products is that they are not always logical in nature - and the math tends to get pretty deep pretty fast.



Rod

It ain't how DEEP it is, it's the damn ROCKS on the BOTTOM...

http://www.whisperroom.com

(got $bux??) (Sorry, no freakin' occult pentagrams...

Geeeeees, Steve, all I asked is it ONE LEAF? I understand about the engineering, the marketing and testing hurdles. Why do you think I called it brainfarts But I still want to know if it is one leaf? You know me, I'm just thinking out loud about this stuff. Its my way of interpreting what I read here. Sorry for bothering you guys with my nonesense.


Thanks for the reality check, again.
fitZ