Second floor studio questions

  • Thread starter Thread starter WagTheDog
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If I go the RSIC/HC route, I'm looking at around $430 just for the clips, then add the HC to that.....quite a chunk out of my budget. If I went with RC only, would I be losing that much isolation, especially since 2 of the four walls will be separate from the outer leaf? It would still be alot better than just nailing the sheetrock onto the studs wouldn't it? Just trying to get the best value for the dollar. If the RSIC/HC combo is THAT much better, I'll go that route. If using RC, I'll just have to be real careful not to short-circuit.
 
Sorry if i post csomething here that has been mentioned previously, but I think its worth mentioning....

The minority of the discussion has to do with the effect of the construction proposed ON THE EXISTING STRUCTURE.
A few points:
>>If you attach ANYTHING to the back of the roof deck, plan on it getting DETACHED over time..specially true of sheetrock. You will someday have to replace you roofing shingles, and the walking on the roof and hammering will knock that stuff off.Come to think of it, the back side of my roof deck has the tips of billions of roofing nails sticking thru it, so flush mounting anything to it would be impossible. ,

On the same note, Do NOT screw up the air flow on the underside of the roof deck. I dont know what the climate is where you live, but you need there is a functional reason for soffet vents and corrigated foam air channels and attic ventilation. This is all to reduce MOISTURE and HEAT, which can damage you structure, promote mold/mildew, provide a nice environment for termites and etc, and etc. You need to keep air flow across the backside of the roof deck and thru the attic.
 
techno,

Yeah, I'm going to go back and drill holes in the board that I used to cover up the soffit area.....

If you are talking about me cutting sheetrock to go between the rafters on the west and east "walls", I'm not going to do that. I couldn't easily do it anyway because the roofing nails stick out from the roof sheathing so the sheetrock wouldn't flush up against the sheathing anyway.

Thanks
 
If the RSIC/HC combo is THAT much better, I'll go that route.
Click to expand...
I gave you a link to the comparison test results. However, it becomes a moot point if the soffet vents are opened as the airgap would not be HEMETICALLY SEALED. At least from MY UNDERSTANDING, a sealed airgap is the most important aspect of a TWO LEAF(MASS AIR MASS)system, as the air is no longer a spring system. This is one of the big problems with building a studio in an attic environment, where the roof framing is part of the airgap system. In that respect, if the sound you generate up there isn't approaching HEAVY METAL level DB profile, perhaps a simple application of 2 layers of drywall directly to the rafters would be a better way to go. I don't know now. Only you can decide, however if I were you I would consult with your local building inspection department. There may even be a code concerning the soffet venting. That might decide for you. If that were the case, I see no advantage to the extra expense for decoupling, as the vents create a flanking path directly out of the airgap. :( Because of this delima, my disclaimer is more important than ever. ;)
fitZ
 
Decoupling/Flanking issues

I'm trying to determine where I might have issues with flanking paths....I'm thinking about doing RSIC/HC on the entire west wall and the east ceiling....and doing either RC or sheetrock-directly-onto-studs for the north, south, and east walls. I have a doubled wall for the north and south and a 4' airgap between the inner and outer leafs on the east wall. From what I can gather from reading, it would not benefit me much to do RC or RSIC/HC on these walls. The reason I'm contemplating doing RSIC/HC on the entire west wall and east ceiling is because the outer leaf is the shingles/sheathing, so the inner leaf will be sharing the same wood stud as the outer leaf. Does this sound reasonable?

One of my big questions though is the decoupling issue with my north/south double wall. Since part of it is nailed to the studs supporting the outer leaf, do I need to use a sway brace? Do I need to do RSIC/HC on everything?

I've posted some pictures that will hopefully point out what I'm talking about.....I'd really appreciate it if someone could take a look and let me know......


Southeast Corner

South Wall

Northeast Corner

Northeast Corner

NorthWest Corner

NorthWest Corner

Southwest Corner

North and West
 
Hello again wag. Well, I looked briefly, which is all it took to see that your double walls serve no decoupling purpose as they are directly tied to the outer leaf framing, no? To me, this impys...yup, you got it..RSIC/HC on everything. At least to my way of thinking. Of course, the ole disclaimer is in force here :) There is something else I see though, and not being a structural engineer, I couldn't say with authority, but are those 2x4 rafters :eek: 24"oc? Hmmmm, if so.... :confused: I'm really questioning this whole scenario.. :o Dang, where is Rod when ya need him? :D Well, time for bed, but I'll look again tomorrow..after 5 workdays, the ole brain is fried. ;) Later
fitZ
 
How then is it possible to build an inner wall without touching the outer wall? It has to touch something doesn't it? So, I built the inner walls for nothing then? :(

The rafters are 2X6 on 24" OC
 
Why do you think they call it "floating". If the interior leaf framing is the decoupling mechanism, it MUST decouple. Otherwise it is useless. In isolation design, hindsight SUCKS. Sorry.
 
I guess the inner wall will serve a purpose though in providing a bigger air gap than I would have had............
 
RSIC clips/window

I'm trying to calculate the number of RSIC clips I'll need.....I've been to several sites that have calculators/diagrams but wanted to get some opinions from HomeRec people who have used them.....specifically how far apart they spaced them, if they used one every 2' on the left/right sides like the diagrams show, etc. Using some of "their" calculations, I will need around 112 which figures out to about $520 or so, just for the clips.

Can anybody give me some "real life" experiences with them?

Also, I have a window that needs to be enclosed....I have a separate inner wall framed already, but I need to know the best way to seal the window up. I was going to just nail up some plywood behind it.....would that work OK or would that create the dreaded third leaf (inner wall, plywood, window)? Would I need to seal the top and bottom also (basically "boxing" it in) or just directly behind it?

Thanks!!!
 
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RICK FITZPATRICK said:
: Hey Inno, I hate to disagree with you but from what I've read directly from Brian Dayton, who works for the company that makes GG, those other products do NOT have the same type of ..elastomeric..(is that the word? :confused: )qualities. Something like that . :p Anyway, its because of this quality that vibration is dampened differently than with Liquid nails or other brands of adhesives.
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But isn't the point to get the two layers acting like one big mass? The elastomeric properties of GG I do not doubt, but that would tend to imply some sort of decoupling function, which is not the goal at that part of the wall system.

Decoupling is what he is spending all that money on RSIC clips!
 
HVAC issue

I had originally planned to split off of my upstairs AC unit plenum, take the duct to the middle of the studio room, and have a return in the studio that tied into the upstairs return.....but I was wondering about an alternative. I have an area in the southwest corner of the studio....I was going to just wall it up.....I'm wondering if maybe I could set a window unit in it......it would use the soffit board air holes for "outside air".....here are a couple of pics:

Southwest Corner1


Southwest Corner2

Would this be do-able?
 
I had originally planned to split off of my upstairs AC unit plenum,
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If you have long seperate serpentine ducts with 2 90 degree bends(min). Otherwise, you create a flanking path for sound to other rooms.


.I'm wondering if maybe I could set a window unit in it......it would use the soffit board air holes for "outside air".....here are a couple of pics:
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Would this be do-able?
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Only if you have a space where the exhaust can exit out the back of the unit. They get the fresh air through vents in the side of the unit. Perhaps if you have a small closet or space down below.
See the drawing. I didn't have time to draw the "return" fan vent, which actually removes air from the studio to the outside without returning it to the plenum. Maybe tomorrow. Here is the concept though.
 

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fitZ,

The measurements for this space are 5' at the bottom, 6' from floor to the top, and 3'4" deep.

My main concern is whether it can draw in enough fresh air from the outside......I have the soffit area covered right now but could open it up again....so really, it should have about 50'-60' of soffit to draw air from.

I assume the hot air exhaust goes out the entire back of the unit? Are you saying I would have to channel this exhaust out and away from the air coming in? Sorry if I'm misunderstanding.....

I can think of several advantages to this.....the upstairs is usually not occupied anymore......my oldest daughter is 22 and moved out several years ago, the youngest is staying here this summer but will be returning back to college in about 3 weeks. So, this setup would allow me to cool just my studio and I could turn the Central Heat/Air upstairs off....it would save some money (seeing that my electric bill this summer has averaged $500, any savings would help!). It would also minimize the flanking effect that may come up with ducting thru the existing HVAC.

What is the difference between a thru-the-wall unit and a window unit?

Thanks
 
Today I talked to a local A/C dealer and showed him my pics. He said it wouldn't work because the unit wouldn't get enough fresh air to cool the condenser....I got to wondering though if I added an "attic fan"......

I have a window in the studio that I was planning to seal up.....I guess I could try a window unit and seal up the rest of the window.....it would be right around the area I would be recording in though, so noise would be an issue.

Very discouraged today :(
 
Hello again wag. Alright, I'm a little confused here. First off, didn't I explain what the AC dealer told you. I thought I did. :confused: Here is more.

A through the wall/window unit has a motor that drives TWO fans. One in the front that pulls warm air from the room through evaporator coils in the front of the unit that contain cool freon gas. This fan also pulls fresh air from the middle air chamber and mixes it with the room air, and then blows it back over a portion of evaporator coils that back into the room. This motor also turns an exhaust fan, which also pulls fresh air from the middle air chamber, and blows it over the condenser coils at the back of the unit. These coils contain HOT liquid freon. This is why the middle air chamber side vents, and the condenser coils must be OUTSIDE. If you mount one of these in an ENCLOSED space, you are heating that space as well as drawing the hot air back in the side vents, even though you have openings to the soffit. See this.
http://home.howstuffworks.com/ac.htm


The measurements for this space are 5' at the bottom, 6' from floor to the top, and 3'4" deep.
Click to expand...
And this space will have holes in the floor over the soffit, no? Maybe I don't understand. How does this relate to this..

I have the soffit area covered right now but could open it up again....so really, it should have about 50'-60' of soffit to draw air from.
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Even if the whole soffit was open, you still can only draw air through what ever opening is in the floor of this space, no? Maybe thats enough. I can't see the whole scenario, so, I'm purely guessing at this point. I wish you could post a pic of the underside of the soffit outside, or draw a section through that space like I did. Mine was pure guessing.

No matter though, you still can't exhaust the hot air into that space which is why this makes no sense...
My main concern is whether it can draw in enough fresh air from the outside...
Click to expand...
Even if it could it would mix with the hot air, and nothing to SEPERATELY pull the hot air out. Thats why I drew what I did. The space below would become a PLENUM, but you would need another fan of some type to pump cold air from this space to your studio, and another to pull an equal amount of air out of the room to the outside. But the MAIN concern, is flanking noise, which I believe this will solve. But only if you have a space below.

Although, there is another option, which would probably solve ALL of the problems. Ever heard of a Mini-Split? Here is some info.
http://www.ductlessdepot.net/standart-51.html
http://www.shopping.com/xGS-Mini_Split_Air_Conditioner~NS-1~linkin_id-7001090~r-1~CLT-INTR

Well, I'm outta time and ideas. Hope this info helps.


BTW, doing the window AC thing is a step in the wrong direction in my opinion though. It is a DIRECT penetration into the space, which is a perfect OPENING for sound to propagate from.

Man, providing HVAC for studios in hot climates can be an expensive and pain in the ass proposition. But recording in a hot, stuffy, airless studio is even worse. :rolleyes: Believe me. I did it for years....fuck it.
fitZ
 
fitZ,

Yeah, I think I get what you're saying....the hot air exhaust from the unit would be mixing with the not-so-hot fresh air going into the unit (and then into the studio)??? Oh well, it was just a thought.....:)

In addition to being a direct penetration into the space, the window faces the street, and the wife was not too pleased at the thought of THAT!

You recorded in a "hot, stuffy, airless studio for years" ??? Sounds like a story there.......

Yeah, I've heard of the mini-split but I'll check out your links also.....thanks!!!

Edit: I read thru the links, thanks. I had an AC guy come out last week and give me an estimate on ducting into the studio and a return out that ties into the existing return, basically tying into my existing HVAC. The estimate was $600 which seems a little high......I've got another guy coming out for an estimate tomorrow or Thursday.

Even at $600 it would be more economical to tie into existing HVAC than even the least expensive mini-split (by the time you pay for labor to hook it up). BUT, I wonder if it would be worth the extra cost to avoid a possible flanking path problem.......
 
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