Building Studio In Pole Barn – Need Construction Advice

[MoBettaBlues]

I'm a newbie so don't shoot me if this question has been asked 1000 times!

I am going to build a studio in the rear of my pole barn. The room/shell will be approx. 24 x 16 x 12 high. This is before construction. The barn has a cement floor and is not finished at all inside. From the outside in the layers are vinyl siding, Tyvak wrap and 9/16” OSB board that is fastened to horizontal 2x4’s and then 4 x 6” posts.

I am probably close to 200 feet from my closest neighbor and approx. 100’ from the closest bedroom in my house. I have not checked the sound levels yet via a meter but it will get to full “Rock Band” (for what that’s worth) levels at times.

I want to keep my costs as low as possible for the “Soundproofing” part of the construction so I can focus on the acoustics within the room and recording equipment. The studio will be used primarily for personal use but I want to be able to use it to record others in the long term.

I was hoping you could offer some basic advice such as:
1) Should I float the floor or not considering the distance from my neighbors and the bedrooms of our house.
2) Should I use a double wall design with 2 sheets of 5/8” drywall on the inside and 1 sheet on the outside spaced 1” from the interior wall of the barn and spaced according to the STC chart to get an STC Rating of +48 with insulation.
3) What STC rating should I try to achieve with this inner room given my circumstances.

I am a veteran musician but I am new to “Studios”. I am working with a budget of $4000 for recording equipment and construction. Probably $1500 for construction materials. I will add acoustic improvements as I can afford them to the inside.

Thank you in advance and have a safe and wonderful holiday season.

 

[Michael Jones]

I'm a newbie so don't shoot me if this question has been asked 1000 times!

I am going to build a studio in the rear of my pole barn. The room/shell will be approx. 24 x 16 x 12 high. This is before construction. The barn has a cement floor and is not finished at all inside. From the outside in the layers are vinyl siding, Tyvak wrap and 9/16” OSB board that is fastened to horizontal 2x4’s and then 4 x 6” posts.

OK, I'll take a stab at this one.
Structurally, your pole barn sounds very sound.
Acoustically, it leaves a lot to be desired.
If the exterior is in good shape, and you can live with its look, then I'd say leave that part alone, and let's concentrate on the inside.

I am probably close to 200 feet from my closest neighbor and approx. 100’ from the closest bedroom in my house. I have not checked the sound levels yet via a meter but it will get to full “Rock Band” (for what that’s worth) levels at times.

Sounds like you don't need a WHOLE lot of isolation, but I think you can do better than an STC of 48.

I want to keep my costs as low as possible for the “Soundproofing” part of the construction so I can focus on the acoustics within the room and recording equipment.

Unfortunately, soundproofing and acoustics are not cheap. If not done correctly, it can end up costing you even more money to fix.

I was hoping you could offer some basic advice such as:
1) Should I float the floor or not considering the distance from my neighbors and the bedrooms of our house.
2) Should I use a double wall design with 2 sheets of 5/8” drywall on the inside and 1 sheet on the outside spaced 1” from the interior wall of the barn and spaced according to the STC chart to get an STC Rating of +48 with insulation.
3) What STC rating should I try to achieve with this inner room given my circumstances.

I am a veteran musician but I am new to “Studios”. I am working with a budget of $4000 for recording equipment and construction. Probably $1500 for construction materials. I will add acoustic improvements as I can afford them to the inside.

Thank you in advance and have a safe and wonderful holiday season.

I think you need to reconsider you budget. $1500 is only about $4.00/sq.ft.
I couldn't build a dog house for $4/sq.ft.
Some other things to consider:
Is there electricity there, at the barn, now?
Is there water? Wastewater?
Will you have a bathroom? Or make people run up to the house, or go in the bushes?
You'll need to Air condition and heat this space. You want isolation from room to room too right?
That's not cheap.
Answer these questions and we can go further.

 

[MoBettaBlues]

Re: Re: Building Studio In Pole Barn – Need Construction Advice

OK, I'll take a stab at this one.
Structurally, your pole barn sounds very sound.
Acoustically, it leaves a lot to be desired.
If the exterior is in good shape, and you can live with its look, then I'd say leave that part alone, and let's concentrate on the inside.

I plan on keeping the exterior intact. No need to touch. This part of the pole barn is 2 years old.

Sounds like you don't need a WHOLE lot of isolation, but I think you can do better than an STC of 48.

Unfortunately, soundproofing and acoustics are not cheap. If not done correctly, it can end up costing you even more money to fix..

Understood.

I think you need to reconsider you budget. $1500 is only about $4.00/sq.ft.
I couldn't build a dog house for $4/sq.ft.
Some other things to consider:
Is there electricity there, at the barn, now?
Is there water? Wastewater?
Will you have a bathroom? Or make people run up to the house, or go in the bushes?

I have a 100 amp 220 service in the barn. I have water out to the barn but a bathroom will not be neccessary. The bushes will do just fine. Actually, the main purpose for this studio is my own personal use and to record my band. If it evolves into a business of recording others that is great. And I would like to keep that in mind for the plan. But for now, my main focus is building a room that is soundproof enough for my location. Then I can use it for my own demos, pre-production, band rehearsals, etc. Then I can improve on the acoustics as the budget allows.

You'll need to Air condition and heat this space. You want isolation from room to room too right?
That's not cheap.
Answer these questions and we can go further.

I'll need heat and air. Isolation rooms will be needed I'm sure. If I can swing I will build them right away. If not I'll build them 3 months down the road.

My main goal is to get this room built within my pole barn. My main questions are:

1) How much soundproofing do I really need for my application?
2) Do I really need a floating floor?

I am approx 200' from my closest neighbor and 100' from my daughters bedroom. My house is a log home so I'm assuming sound will not be an issue. If I don't need to float a floor my cost will be much better.

I really appreciate your help.

 

[Michael Jones]

Re: Re: Re: Building Studio In Pole Barn – Need Construction Advice

I plan on keeping the exterior intact. No need to touch. This part of the pole barn is 2 years old.

OK. Good.

I have a 100 amp 220 service in the barn. I have water out to the barn but a bathroom will not be neccessary. The bushes will do just fine. Actually, the main purpose for this studio is my own personal use and to record my band. If it evolves into a business of recording others that is great. And I would like to keep that in mind for the plan. But for now, my main focus is building a room that is soundproof enough for my location. Then I can use it for my own demos, pre-production, band rehearsals, etc. Then I can improve on the acoustics as the budget allows.

Fair enough.
Personally, I'd like to have a bathroom, but, hey, I've been known to go in the bushes before too.
But give it some thought. Think "long term use". What if some day you're tracking a female singer-songwriter? She's not going to want to "go in the bushes", and the interruption of having to go up to the house can really break a creative flow.

I'll need heat and air.

Then start off by calling some HVAC contractors. FInd out how much, even a basic, central AC/Heat system will cost you.
I'm going to bet you right now that that alone will cost you more than $1500.

My main goal is to get this room built within my pole barn. My main questions are:

1) How much soundproofing do I really need for my application?
2) Do I really need a floating floor?

I am approx 200' from my closest neighbor and 100' from my daughters bedroom. My house is a log home so I'm assuming sound will not be an issue. If I don't need to float a floor my cost will be much better.

I really appreciate your help.

A floating floor:
You have a concrete slab on grade; that's pretty good iso, and darn good "bang for the buck".
It just depends on how elaborate you want to get. It doesn't sound to me like you have it available in your budget though.

Here's a chart showing STC ratings for various types of construction.
http://www.saecollege.de/reference_material/pages/STC Chart.htm
Some one else will probably chime in on these ratings too, but I think, in theory, those STC ratings are a measure of resistance to sound - a transmission loss - in dB - when compared to a standard curve.... blah, blah, blah...
http://www.maconline.org/tech/materials/sstoc/sswalls3/sswalls3.html

So? What does that mean?
It means if you're going to record a rock band at 2:00 in the morning, and you don't want to wake some one up, in a bedroom, 100 feet away, you probably want a fair amount of sound reduction. But there may be "work arounds".

How loud is a rock band?
Pretty lound I bet. Especially if you're doing drums.
Here's some typicals:

Near total silence - 0 dB
A whisper - 15 dB
Normal conversation - 60 dB
A lawnmower - 90 dB
A car horn - 110 dB
A rock concert or a jet engine - 120 dB
A gunshot or firecracker - 140 dB

So, you're looking at around 110-120 dB.
Now, Decible ratings are a logrithmic scale.
Something at 100dB is not just twice as loud as something at 50dB. In fact its about TEN times as loud!

Now, if someone was talking, right outside of that bedroom window, would you hear them?
Imagine that's sort of how it'd be with an STC of 50dB for the studio. (Not really, but close enough for an example)

So YOU need to decide how much sound attenuation you need.
Keep in mind though, that sound can leave the studio, but it can also get in to it as well. (dogs barking, horns blowing, lawn mowers...)

Work up a floor plan. Post it here. Take a picture of something sketched on the back of a napkin if you have to.

There MAY be ways to work something out for $4000, but not for $1500. I hope your good with a hammer. And remember! Call some A/C contractors first. Find out what you're looking at there.

 

[Michael Jones]

Oh yeah.
There's another member here, Rick Fitzgerald.
He makes us call him "fitz". ( Yeah, I know.)

He's doing a pole barn conversion. I'm sure he'll chime in with lots of insight and ideas too.

 

[adam]

I am by no means the most informed of folks on this board, but as I understand it a floating floor is more for creating a separate/detached area for isolation purpose - typically between a live room and a mix room. In a home environment it would help from sound waves traveling to other parts of the house. It doesn't sound like you have either of these situations.

 

[knightfly]

I'm pretty familiar with pole barn construction - are your horizontal 2x4's laid flat against the OUTSIDE of the 4x6 uprights, so that the space between uprights is currently NOT filled with anything, even a frame? If so, which way are the 4x6's oriented - is the 6" dimension what determines the thickness of the wall, or is it the 4" dimension?

What about overhead structure, can you describe the roof construction as you did the walls, including size of framing, spacing, etc?

Are those dimensions the actual outside measurements, or inside the 4x6's, or what? You really do NOT want to end up with those as inside dimensions or you'll eat your entire budget just with acoustic treatment, probably more.

I saw one thing in your post that makes me say, STOP!!! Well, OK, several - but for sound proofing - do NOT, repeat NOT, build anything in the way of walls until you understand the basics of soundproofing or you will waste all your budget and STILL be able to hear exactly what each band member is playing from the house. Been there, done that over 20 years ago...

Here's an old thread on an outside practice room that answers a lot of questions about soundproof construction, if you read all the way through it you'll get a good idea of some things NOT to do as well as things TO do. (Just ignore the part where I said to put RC on with the wide part facing down, that was an "after graveyard shift" brain fart)

http://www.homerecording.com/bbs/showthread.php?s=&threadid=88275&perpage=20&pagenumber=1

Main thing to remember for sound proof construction - no matter how many layers of mass you use, they should ALL be in only TWO locations, with only ONE air/insulation space between. This includes anything a sound would have to get through from any one area to any other area.

Check out the thread, Jim seems to be pretty happy with his results -

Michael is giving you good advice though, your budget won't get you there (although Jim needed a floor, and you don't, so it will be closer than if you started from scratch)

If you're not into frustration, please don't build anything without discussing it first - so far, there's been about a 1% chance of getting it right without knowledgable help... Steve

 

[MoBettaBlues]

Thanks All.

I will be replying to your questions and advice at another time. I'm preparing for a location move here ate work and don't have time to reply in detail.

Did'nt want you to think I was ignoring you and/or unappreciative of your advice.

Talk to you soon!

 

[MoBettaBlues]

Knightfly,
It's going to beanother busy day here and I want to get some good sketches together to give you a good idea of what my current construction is and what my current plan is.

I read the thread on the "Outdoor" building. Wow! Long but informative. Right now my biggest sigh is if I need a floating floor. I really hope I don't. My pole barn/slab is 24' x 44' and has a 24" deep rat wall. I spoke with the owner of "Alliance Studio's" 2 days ago and he didn't seem to think I needed a floating floor. I want to provide you with my plan based on what I learned from his advice and see what you think. Might take me a couple of days to get this together so please don't give up on me. I really want your advice.

However, here are some answers to a couple of your questions:

I'm pretty familiar with pole barn construction - are your horizontal 2x4's laid flat against the OUTSIDE of the 4x6 uprights, so that the space between uprights is currently NOT filled with anything, even a frame? If so, which way are the 4x6's oriented - is the 6" dimension what determines the thickness of the wall, or is it the 4" dimension?

The answer is yes to the above questions and 6" thickness.

More to follow soon. Thanks again!

 

[MoBettaBlues]

Well I'm back with some details.

I'll get right to the point:

I have attached several JPEGS showing my current construction. The OSB in the walls is 5/8" and 7/16" in the ceiling. The picture of the "Eave Detail" shows T-111 for siding. Refer to my sketch for the actual materials wich are from the inside out: 5/8" OSB, Tyvak Wrap and Vynil Siding.

I hope this works. I'm new to posting pics.

 

[knightfly]

Looks like you got about half of your drawing for some reason - no hurry though, I'm on 12-hour graveyard thru Christmas so take your time... Steve

 

[MoBettaBlues]

Eave Detail:

Please note the 2x12 shown at the inside top of the 4x6 pole is the only lumber that protrudes inward and beyond the 4x6 pole itself.

 

[MoBettaBlues]

Plan View of Pole Barn:

The overall size of my barn is 24' x 44'. My studio will be at the back and will be 24' x 16'. The height from floor to bottom of truss is 12'. The poles are spaced approx. 8' apart and the 24' dimension is taken from the inside side of the OSB.

 

[knightfly]

You say that the only lumber inside the 4x6's is that 2x12, yet you show a 2x4 girder block just under the 2x12 - does that block extend all the way to the floor?
Is the cement floor even with the outside of the poles as shown in your floor plan?
And am I correct in assuming that the space between your sheathing under the vinyl siding, is really where the horizontal 2x4's are placed, and that they run horizontally as mentioned, but are spaced vertically every two feet?
Are there vents in your soffits so that the roof can breathe? (This is important for ceiling details so we know what to put in for an inner ceiling)

Gotta run, more later... Steve

 

[MoBettaBlues]

You say that the only lumber inside the 4x6's is that 2x12, yet you show a 2x4 girder block just under the 2x12 - does that block extend all the way to the floor?
Is the cement floor even with the outside of the poles as shown in your floor plan?
And am I correct in assuming that the space between your sheathing under the vinyl siding, is really where the horizontal 2x4's are placed, and that they run horizontally as mentioned, but are spaced vertically every two feet?
Are there vents in your soffits so that the roof can breathe? (This is important for ceiling details so we know what to put in for an inner ceiling)

Gotta run, more later... Steve

No. Sorry. Actually there is no block at all.

Yes the cement floor is even with the outside of the poles. In other words, it is also even with the horizontal 2x4 side girts (as they are called)

Yes the horizontal 2x4's are directly under the 5/8" OSB sheathing and the 2x4's are fastened directly to the outside of the 4x6's. From the inside of the barn you see the 2x4's with the sheathing fastened to them on the outsides.And yes, they are spaced 2' vertically.

One more minor detail: The 4x6's at the back of the barn are turned 90 deg so the 4" dimension makes up the wall depth.

The barn is completly unfinished on the inside with the exception of a 100 amp service panel, a few oulets and lights. I will be able to do all electrical work and construction. HVAC will be contracted out. I have a ood lead on an HVAC guy that was recomended to me by a studio owner.

The soffits are so that the roof can breathe. The eave detail shows the trusses sitting on top of the 2x12's which are fastened to bothe sides of the 4x6's. The trusses are spaced 2' on center.

Sorry about the picture showing up 1/2 way. I am now on my daughters laptop. I screwed up my PC after installing some anti-virus software. Now I can't get on line!

I hope I have given you enough details to go by. If not, please let me know what you need and I'll get it to you ASAP.

Have a Merry Christmas Steve!

Jeff

 

[knightfly]

Jeff, I think we've got enough to get started on - realistically, it'll be a day or two (bah humbug day, etc) before I can do much. Your existing wall construction will be a bit of a challenge if we're to balance some of the needed mass to the outer leaf which would make it easier to get acoustics done with less trapping, etc - you may just have to plan on a few more bass traps inside due to the flat 2x4's being in the way of making a heavy mass outside with no extra air space (a BIG no-no) -

I figured your soffits were vented, but wanted to make sure. They should be, but you never know... All that means is that you can basically ignore the roof layers and will need two more isolated leaves for your ceiling. That too may be a challenge, when it comes to integrating the wall and ceiling detail in order to maintain two independent mass leaves all around your space.

Anyway, I'll probably get a chance to dig into this in the next couple of days - meantime, Merry Christmas to you and yours... Steve

 

[RICK FITZPATRICK]

Hello Jeff and Merry Christmas. Fitz is what I use as a nickname, Rick is my real name. And actually,contrary to what some people say, my last name is Fitzpatrick. No offence. Just to set the records straight. Some call me by other less than complimentary names .

Well, it looks as if I'm going to have to join in this one. I am a detailer. Consequently, I deal in REAL dimensions, otherwise how can one describe EXACT details here. Sooooooo, I'm here to help. If you don't mind. All I'm here to do is interpret what you and others say, and put it in a form for everyone to see in its correct existing reality, so when Steve and others want to tell you something, they have real stuff to show. Therefore, here is our starting point. The existing PLAN.

What I need, is accuracy. Not generalitys. Thats the only way my help can truly be utilized. So, I need you to confirm some things if you don't mind.

First, the 24' dimension. Where is it REALLY come from. The outside corner of the corner of 4x6, to the outside corner of the opposite corner 4x6? That is the way I drew it. However, if that is correct, then it should be EXACTLY 288" from the inside face of the 2x4, to the inside face of the opposing 2x4 on the opposite side of the room.

Next, the 16' dimension. Where does it REALLY start and end. I drew it as staring at the outside corner of the corner 4x6, to the centerline of the THIRD 4x6 from the corner, includiing the corner 4x6. Please verify EXACTLY the dimension as shown.

See how hard that is to describe. Therefore, we will set up descriptive names for the directions(NORTH,SOUTH,EAST, WEST) and the grid lines of the colums. See the pic below for the gridlines. For our information, tell us which direction the left wall(24' dimension) faces. That should be the wall that is the left end of the WHOLE building, as per YOUR drawing. I did not lay out the whole building. Only that portion which is to be your studio. At least for now.

I have assigned a set of grid numbers and letters to describe the column centers. You will see this in the SECOND picture below. I have to post a reply for every picture that I want to show right in the post. But from now on, MOST will be a URL on my server. That way I can post numerous pictures, unless I REALLY want to get your or someones attention.

Next, I need to know EXACTLY, where the slab dimensions are coming from. In my mind, the inside face of the OSB SHOULD align with the edge of the slab. The outside face of the 2x4, also should align with the edge of the slab. Otherwise, how could the OSB seal the building. Although I've seen buildings where the builder didn't have a clue to what he was doing. If the slab extends beyond the vinyl siding, OH BROTHER, that would mean moisture would collect on the top of the slab and wand to weep in under the osb and siding. So, please verify these details right from the gitgo. AND, any other relevant oversights. OK. However, if you don't need this sort of help, just say the work and I'll butt out. If you DO want my help, then provide these answers and we will start out on the right foot. Cause everything you do from this point out, will be determined by what is existing, and the help here will only be as good as real existing dimensions given.

Ok, I am labling the far upper left corner column, as a vertical gridline noted as "A", which in the FIRST drawing, is shown as aligning with the outside face. That was for 1/4" scale plan overall dimentsions. However, in the detail, the actual grid is on the centerline. The horizontal gridline, aligning with the LONG wall of the building, is actually the center line of the CORNER post, which has been turned 90 degrees from the posts inbetween corners. It is labled grid "1". I will clarify this later, after you supply some dimensional answers. Like for instance, IS the dimensions given for a 4x6, REALITY? Most lumber now days, ard labled in NOMINAL dimensions. 2x4, 4x4, 4x6, etc. However, their TRUE dimensions, given shrinkage and small variances, will be somewhat smaller. Usually, by nominal standards, a "2x4", is 1 1/2"x 3 1/2". The reason I ask, is I have found MANY instances of custom MILLED material that is the actual size of material that is given in nominal dimensions. Old 2x4 etc, from as late as the 60's, were the actual size of the given dimensions. Thats why I asked.

Anyway, lets get going, no time to waste here. So here is the starting grid plan and a detail of that corner, labled A/1. See how easy that is. Cool. So, let me know. If you really don't need this sort of help, good luck with your studio, as it is the ONLY real help I can offer. Acoustic and constructional help is already answering here, drawing is my expertize, as well as construction and fixture detailing, and actually, by the time you finish these sessions, you could probably use these plans as a backbone for many other things. Electrical, HVAC, Permits, etc. But the choice is yours. Its only an offer.

fitZ

 

[RICK FITZPATRICK]

Here is the corner detail. I assumed a couple of things.

BTW, after viewing this here, I see the conversion from .dwg to .gif, is less than high resolution, as some of the dimensions text, doesn't SHOW UP. Crap. Sorry. Nothing I can do but clarify as we go. Damn.

 

[RICK FITZPATRICK]

Hello Jeff, I decided to include this little layout from templates I have in my studio files, just to give some scale to your space. This is by no means an actual layout. Sometimes, a blank drawing, with nothing to gauge size, leads to unrealistic conclusions. Hope this helps. The items are drawn to scale so you can see what you are working with. Usually, people overestimate the space they have. Especially when they start to enclose rooms with in a room.
Also, the dimensions shown, when converted to .gif, loose the number 1 for some reason. At least in vertical dimensions. For instance, the dimension 8" should read 18".
Which is where your monitors should focus behind the engineering position. Others are 106", 154" etc. What a crappy way to do things, but its the nature of conversion from high resolution to low for posting here.. Sorry

fitZ

 

[knightfly]

Jeff, I just added up the cost of only the wallboard needed for all necessary layers to enclose your room - figuring 3 layers around the outer 3 walls and 4 layers for the inner wall and ceiling, based on $6 per sheet I get around $880 just for sheet rock. Without considering anything but enclosing and sound proofing, you'd still need framing material, resilient channel, acoustic caulking and an exterior solid core door, with either custom fabrication or factory seal kits to get the door sealed. Once the room is sealed, you then have to violate that seal for ventilation, whether you use Air conditioning and/or heating, or not. For just basic ventilation, you can use home made ducting with several bends in it and a quiet house ventilation fan. For actual HVAC, it gets more expensive and more complex.

Your layout, assuming there is any sound reduction contributed by the overhead door, may work without a sound lock (vestibule with two doors, separated by a few feet) or you may need to add this either inside or outside the space if you don't get enough isolation for your needs.

For what you want to do, I'd forget floated floors - later, if you add an isolation area outside the present plan, you may want to build a floated room for drum isolation, etc -

I personally wouldn't make two separate rooms in the space you're allocating right now - when you cram a full band and gear in there, anything tighter than 14-1/2' by 22-1/2' (what you can expect after sound proofing) will get pretty cramped. I used to practice with a 5-piece in about 12 x 22, complete with PA and lights, set up just as on stage (helps to know where to look for various cues, etc) - anyway, that was about minimum I'd ever try - prior to that, we were practicing in a 15 x 16 living room - even if we'd been able to take out the couch, it would have been tight.

For sound proofing, the ONLY thing that works is having TWO separate leaves of mass separated by an air space, which can and should have insulation inside. Anything else is a total waste of time, material, money and effort and can actually REDUCE the amound of isolation you get.

Your outer skin and framing are going to make achieving that condition fairly difficult, but I think it can be done. First of all, since your roof is ventilated that doesn't count for one of the two leaves - however, unless you're willing to drill several large holes in your outer walls, (dumb idea) that mass WILL count as one of your two leaves. It's not very solid from an acoustic viewpoint, but it would be pretty tricky to add mass to that leaf at this point - Whatever mass you did add to that leaf, would need to end up flush with the inner edge of your flat 2x4's (as in, between them) so you don't introduce another air space as part of that leaf. Remember, you only get one air space and it needs to be as deep as possible for better isolation. Up to about 12", every extra inch of air space between inner and outer leaf helps a lot and only costs you inner room floor space.

If you can't make your outer wall heavier without adding air, then you will need to make your inner leaf heavier (more layers) to compensate. This will mean that once you're in, you'll need more bass trapping in the room because of the stiffer inner wall leaf.

If it's possible to accomplish, the best way to handle all this might be to put three layers of 1/2" wallboard between your flat 2x4's and up against the OSB, using construction adhesive around the inner edges and caulking along the 2x4's with acoustic rated caulk. Then, on your inner walls, you could start with just one layer of wallboard properly caulked - if that isn't enough isolation, you could add 1 or 2 more layers, with seams offset, proper caulking, etc; that way, you would have options if the initial construction didn't solve all your noise problems.

From your drawings, it appears that your roof trusses are 2x4 - are these actual engineered trusses, and if so can they support two layers of wallboard on their underside? If so, that's your first leaf of your ceiling. If not, a different approach will be needed.

One way to handle this would be a completely separate inner frame, including ceiling joists of 2x12's on 24" centers - your inner leaf would go on the inside of this frame, with resilient channel supporting the inside layers of ceiling wallboard - the outer leaf would be a little tricky, because you'd need to make one continuous leaf of the outside wall and the double layer of wallboard placed on the top of your new 2x12 ceiling joists. The area between the inner and outer ceiling would be heavily insulated, with at least 12" spun fiberglas batts. The inner ceiling layers would be suspended on Resilient channel, for an improvement of around 10 dB - about 49 dB without, 59 dB with the RC. That's figured using two layers of wallboard each side, one side double 5/8 and the other side using one layer of 5/8 and one layer of 1/2". Note that your low frequency Transmission Loss won't change with or without the RC, since that's pretty well maxed out by the 2x12 joists. These will be necessary, BTW, more because of span limitations with 4 layers of wallboard.

The main thing you need to look at right now, is a way to continue your outer OSB layer across the ceiling with no breaks in the mass layer - if that's not feasible, then the new ceiling joists can take enough weight to handle it and you'll only need to figure out how to bridge between the outer ceiling layers on top of the new joists, and the outer wall so that is one continuous barrier.

I'm outa time for now, hope this helps you figure out what's next - Here's some interesting videos from Michigan state code, hope you have broadband or they might be pretty slow -

http://www.michigancodes.com/module9.html

The sill seal one may apply to your inner framing - makes better joint between sill plate and concrete... Steve