Any suggestions to maximize isolation?

We are about to start building our live room and I am concerned with the potential for sound transmission to our upstairs neighbors, a residential apartment. I've attached a jpeg with a rough outline for our construction plan, there are no measurements yet and the drawing is not to scale. The control room portion of the drawing has already been built; the windows have not been installed. Am I going to need to install 4 windows with this construction method? Will this provide sufficient isolation for our neighbors? Thanks, Sam

Sammy, welcome; please do NOT build anything further til you go here http://www.johnlsayers.com/phpBB2/viewtopic.php?t=3231 and follow ALL the bolded points - you are apparently already into "multi-leaf" territory, and you do NOT want to go there; more money, less isolation, less headroom for more disappointment. It will take several hours of reading thru at least the first 3 links on that page, but will probably save you 10 TIMES that in "Aw Crap" comments alone... Steve

Thanks for the reply Steve, I apologize for the lack of background details in my previous post. I read through the links, found some good info and am ready to try again. My business partner and I are building a recording studio in Chicago. Our building is a storefront on a busy street with lots of honking horns, trucks clanking and loud music from passing cars. We have the whole first level and above us is a three-bedroom apartment. Below us is the basement. The facility will include a front office, behind that will be the live room, then the control room, and finally, there will be a lounge in the rear of the building off the alley. The original structure is brick from the street to where the live room ends and the control room starts. There is a 3’ wide gangway on either side of the building. The lounge and the control room are in an aluminum siding addition that was added to the main building at some point. The addition is only one story, so it acts like a deck for the upstairs apartment. It is also about 2 feet above the level of the existing structure. There is a significant step up from the live room to the control room. The exising floors and ceilings are not airtight. Just plywood or hard wood slats over ceiling joists, as far as I can tell. We plan to use the control room mostly for post-production, mixing, mastering, and electronic music production. We will probably only be tracking in the live room a couple days a month. The rest of the time we hope to rent the live room as a rehearsal space for rock bands. Potentially very loud. Since it is likely I will often be using the control room for my own projects while there is a band rehearsing in the live room, and since there are people living directly above, my top priority is eliminating noise transmission from the live room. The upstairs neighbors are friends of the studio, but they won’t remain so for long if they are kept awake at night by bands rehearsing below. I am much less concerned with noise coming in from the street, or noise escaping from the control room. We are well into the construction process. The control room is almost completely done; there are no windows installed and we still need to finish the trim around the doors. My business partner is a carpenter by trade; he is doing most of the actual work, so forgive me if I don’t have 100% accurate measurements. The floor is floated on rubber pucks and cantilevered 3-4’ over the ledge (remember the live room is 2 feet lower than the control room). On top of the studs we’ve laid one layer of plywood, one layer of drywall and one layer of mdf. All are 1/2'” I believe. There is an outer wall, wood 2x4s, 16” on center, built on top of the floating floor with 2 layers of ½” drywall on the inside surface. This outer wall supports a ceiling, wood 2x4s, 16” on center, also with 2 layers of ½” drywall. Then there is a 1-2” air gap and an inner wall supporting an inner ceiling with the exact same construction techniques as the outer wall. I know there are 2 big problems with this design. First, the leaf on the outer wall should be on the opposite side of the studs, the outer side, not the inner side. Second, we should have used different width drywall on the inner wall so as to not match the width on the outer wall. Any other issues with this technique I should be aware of? The live room has not been built yet, but my partner will probably build the live room the same way as he did the control room, unless I tell him other wise. My question for this forum is: what should we do differently in the live room to maximize isolation? Would it be better to build the outer shell on the existing floor and then float the inner shell on rubber pucks inside of that? We are looking at a budget at or around $5000. My other question is about window installation. Since I have two shells in the control room, should I install two windows? They share the same floor, couldn’t they share the same window? Remember, I am not that concerned with noise transmission in the control room. The live room is where I want to focus my energy. I can post more pictures if you need me to clarify something. Thanks, Sam

Wow! :shock: I thought I had heavy duty isolation requirements, but you, sir, take the prize! What are the noise ordinances that apply to your part of town and to your type of construction (mixed use retail & residential)? It would seem to me that would be your absolute minimum target noise levels, and you'd preferably want to exceed that significantly so that you have some wiggle room. Got drawings? Photographs? --Keith :mrgreen:

I'm not sure what the noise ordinances are in Chicago. But like I said, it is a really busy street day and night, people don't expect absolute silence. In fact, in the part of town where we are building, there are a number of live music venues at street level with absolutely no soundproofing. Obviously there is a ton of leakage out onto the street at these places. I'm really not worried about transmission loss at street level. What concerns me most is isolating the space for the sake of the upstairs neighbors. I looked at your thread, Keith, and got some good ideas. I think we have similar requirements. Here is a quick drawing of the plan for the live room. The black lines represent existing walls. Redish boxes are bricks, the blue lines are where I would like the live room to sit in the space. However we are very flexible about this

I was at the studio today and I got some more details about the construction of the existing space. The east and west walls are brick with 1"x2" firring strips on the inside, on top of which is plaster and lath. Part of the north wall shares this type of construction because this wall is the end of the original structure. The control room is already built just beyond the north wall, using 2x4s 16" OC and 2 layers of drywall, the whole thing is raised about 2 feet above the level of the rest of the building. A portion of the control room is cantileverd out into the space where we will build the live room. I know this is convoluted and is probably hard to visualize. I will post pictures tonight or tomorrow. The south wall is just floor to ceiling metal studs with one layer of drywall on the opposite side. We've got a 12' high ceiling. The flooring above is nailed to 13"x3" wood joists, 16" OC, running east/west. On these joists are plaster and lath, like the walls. There are a number of penetrations through the plaster and into the apartment above, like conduit, plumbing and gas. Our floor boards are nailed to 6"x4" beams, 16" OC, above a 5 1/2 foot concrete basement. Any suggestions on how to approach this room are welcome. It seems the more I read about other people's project, the more lost I get. I've got some ideas, but no solid plan of attack is forming. The walls and the ceiling have a ton of plaster on them. If there is anyway to avoid removing it all, I'd be thrilled. I'm willing to sacrifice as much space as I need to. We've got plenty of height to work with. Another factor to consider is time. We need to get this room operational by January 1. Thanks in advance for any assistance. Sam

sammy87 wrote:

I'm not sure what the noise ordinances are in Chicago.

Here are the noise regulations in Chicago. It appears that there decibel limits for specific frequencies, and those limits vary depending on the district. This item jumped out at me:

11-4-1380 Public nuisance declared--Abatement. Any emission of noise or earthshaking vibration from any source in excess of the limitations established in or pursuant to this article shall be deemed and is hereby declared to be a public nuisance and may be subject to summary abatement procedures. Such abatement may be in addition to the administrative proceedings, fines and penalties herein provided. The commissioner is empowered to secure the institution of legal proceedings through the corporation counsel for the abatement or prosecution of emissions of noise and earthshaking vibration which cause injury, detriment, nuisance or annoyance to the public or endanger the health, comfort, safety or welfare of the public, or cause to have a natural tendency to cause injury or damage to public or property. Such legal proceedings may be in addition to the administrative proceedings, fine and penalties herein provided.

Print out the whole thing and study it carefully, get confused, read it again, get more confused, and hopefully after a few more rounds, it will start to make some sense. If not, call your city's Environmental Complaint Line and see if you can speak with someone who can answer your questions.

But like I said, it is a really busy street day and night, people don't expect absolute silence. In fact, in the part of town where we are building, there are a number of live music venues at street level with absolutely no soundproofing. Obviously there is a ton of leakage out onto the street at these places.

From what I gathered from my cursory review of the regulations, they may be in violation of the law; if so, they're getting away with it for now, but that could change if there's a crackdown at some point in the future.

I'm really not worried about transmission loss at street level.

Maybe you should be. :roll: I would hate to see you build so nicely, only to be shut down in the future.

What concerns me most is isolating the space for the sake of the upstairs neighbors.

Yes, that is quite understandably the greater concern. --Keith :mrgreen:

Thanks for the heads up, Keith. I'll check those resources and make sure we are in compliance. I'm reading through other people's threads, and learning more as I do, but I still have a ton of questions. We want to start building as soon as possible, but I'd love some guidance from members on this forum before we just jump in and end up making dumb mistakes. I understand that the most efficient method of isolation is mass / air / mass. I should probably use our existing walls and ceilings as the outer leaf in a two leaf system. However, the existing structure is not up to snuff as far as being airtight, certainly not the existing ceiling nor the non-brick walls to the north and south of the live room. It would take a TON of time and effort to get them workable, more than we can afford. In cases like this, is it okay to "start from scratch?" By that I mean, Can I build a new outer leaf withing the existing structure, making sure that it has plenty of mass and is airtight, and then float the inner leaf inside the new outer leaf? I could provide the same size air gap between these two new leaves as I would if I were using the existing structure as the outer leaf. Unless I hear differently, I imagine we will end up suspending a new ceiling from the existing one, and building new walls to meet this new ceiling. We would cover all surfaces with 2 layers of 5/8" drywall and caulk all of the seams. Within this shell, we would float a floor of plywood and mdf on rubber pucks and build walls on top filled with fiberglass insulation. The inner walls would support the inner ceiling, also filled with fiberglass insulation. We'd cover all surfaces with 3 layers of 1/2" drywall and caulk all the seams. Will this work? How much transmission loss can we expect if it is carried out properly? What details am I missing, or what variables am I overlooking? Sam

sammy87 wrote:

I'm reading through other people's threads, and learning more as I do, but I still have a ton of questions. We want to start building as soon as possible, but I'd love some guidance from members on this forum before we just jump in and end up making dumb mistakes.

We won't be shy! ;) Just develop your plans and "think out loud" here. We'll do our best to keep you out of trouble.

I understand that the most efficient method of isolation is mass / air / mass. I should probably use our existing walls and ceilings as the outer leaf in a two leaf system. However, the existing structure is not up to snuff as far as being airtight, certainly not the existing ceiling nor the non-brick walls to the north and south of the live room. It would take a TON of time and effort to get them workable, more than we can afford. In cases like this, is it okay to "start from scratch?" By that I mean, Can I build a new outer leaf withing the existing structure, making sure that it has plenty of mass and is airtight, and then float the inner leaf inside the new outer leaf? I could provide the same size air gap between these two new leaves as I would if I were using the existing structure as the outer leaf.

I think I understand your question. You're wondering if you can kind of "ignore" the existing structure so you can focus on building two new leaves. Sometimes that's necessary. However, you mustn't underestimate the detrimental effect of extra leaves. If you gave me a bunch of building materials, I could build you a two leaf system and you'd have a certain level of soundproofing. Then if I took it all apart and reassembled it differently, using the exact same amount of mass and ending up with the exact same square footage, only I spread the mass around so that we had three or even four leaves, the room would suck. There are was to mitigate the effects of third and/or fourth leaves. I have a third leaf in my project -- it's my roof. However, my attic is vented and the first two leaves (ceilings) will be plenty beefy with a decent sized gap between them (about 12"), so this is a calculated risk. You may have no choice but to deal with the imperfections in your existing structure. However, without any photos or detailed illustrations showing these items, it's hard to get specific.

Unless I hear differently, I imagine we will end up suspending a new ceiling from the existing one, and building new walls to meet this new ceiling. We would cover all surfaces with 2 layers of 5/8" drywall and caulk all of the seams. Within this shell, we would float a floor of plywood and mdf on rubber pucks and build walls on top filled with fiberglass insulation. The inner walls would support the inner ceiling, also filled with fiberglass insulation. We'd cover all surfaces with 3 layers of 1/2" drywall and caulk all the seams. Will this work? How much transmission loss can we expect if it is carried out properly? What details am I missing, or what variables am I overlooking?

You're basically on the right track. I don't have the fancy calculators to predict the performance of that system (and, mind you, there are still incomplete parts of the equation, such as the size of your air gap between the leaves (measured from the backs of the drywall -- the studs don't count, as long as each leaf is completely decoupled) and the situation with your existing structure. You'd probably be better off beefing up your existing leaf rather than hanging a new ceiling on the bottom of the joists. It's more time consuming but the effort will pay off in spades. I spent several hours doing this to my east wall today. Just make sure you don't overload that ceiling, or people will die!!! :evil: You'll probably need to up the ante to three layers of drywall and maybe four. You'll also probably want to use 5/8" instead of 1/2" -- more mass, same effort. You may also want to use Green Glue somewhere -- I'll leave the specifics of that advice to Steve or others who may have more knowledge of it. (I only became versed in Green Glue in the last 24 hours -- I'm the wrong person to ask about it yet.) Regarding the floating floor -- you may end up with a floor that, in spite of your best efforts, is actually worse than the floor you currently have. What kind of floor are you on now? Concrete slab? You're on the ground floor, right? I debated floating a floor for ages. I ultimately decided to replace my lousy garage floor with a structural grade isolated slab. Mmm, that will be fun (not). Time for us to see photos and detailed drawings of your space. Don't forget to include utility locations (water valves, electric service panels, drain pipes, water heater -- stuff that probably can't be moved and/or must be accessible and servicable). Take a deep breath and muster up as much patience as you can. Borrow some if you need to. You're in for quite a rollercoaster ride -- but you're not alone and there are some very helpful folks here to get you unstuck when you need it. 8) Please tell me you're getting permits for all this... You're in commercial space, right? That makes it all the more important -- try to fly under that radar and you're sure to get nailed, especially in a big city like yours. --Keith :mrgreen:

Keith your spoiled because you dont complicate your life like I do. Im not sure I have the details, but if your going to use the roof as leaf 1 then you are now venturing in to the unvented attic realm. Its not fun. check it...http://www.johnlsayers.com/phpBB2/viewt ... highlight= it somewhere closer to the end..

Mike, did you mean to reply to this thread? Because our Chicago friend here has a residential neighbor above his commercial space -- not an attic. For the record, I will have two very beefy ceilings on my project about a foot apart. I don't need to worry about the unvented attic stuff. --Keith :mrgreen:

sorry, lazy, but i do remember reading about that a little while ago. And thats what I meant when i said you dont have to worry about it because you dont complicate your life is refering to the fact Im set on having a high as possible ceiling which has forced me to even be able to say UNVENTED attic. My apologies, Ive been away a minute, and Im a little rusty and trigger happy. Its just when you mentioned the whole outer leaf is structural thing it flashed me back to when you figured out that if my roof was vented, its not a leaf. Strike that one from the record..

I was posting under the influence

sorry, lazy, but i do remember reading about that a little while ago. And thats what I meant when i said you dont have to worry about it because you dont complicate your life is refering to the fact Im set on having a high as possible ceiling which has forced me to even be able to say UNVENTED attic. My apologies, Ive been away a minute, and Im a little rusty and trigger happy. Its just when you mentioned the whole outer leaf is structural thing it flashed me back to when you figured out that if my roof was vented, its not a leaf. Strike that one from the record..

I was posting under the influence

:lol: :lol: :lol: :lol: :lol:

Friends don't let friends hijack peoples' threads with incoherent ramblings. ;) Don't you have a designated typist? --Keith :mrgreen: For those who don't get the pun -- there was a big anti drunk driving campaign years ago here in the U.S. The motto was "Friends don't let friends drive drunk."

Plan below.

This was supposed to be at the bottom of the above message, sorry. A: neighbor's flooring nailed to our existing ceiling joists B: existing 13" x 3" ceiling joists, 16" on center C: existing conduit and gas pipes which run along our existing ceiling or up from the basement, through our space and into the apartment above. This is the biggest reason why I don’t want to use the existing structure as an outer leaf. Soundproofing around all these penetrations (over a dozen, maybe two dozen) would be a colossal headache if not impossible. D: plaster and lathe on ceiling joists, there are huge holes in this layer. Nearly a quarter of it is missing. E: New 2" x 6" ceiling joists, suspended from the existing joists with 2" x 4" strips. This would be done to get below the pipes and conduit so that we can have an outer shell without penetrations. Would it be better to suspend this with something more resilient than 2x4s? How much space should I leave here? Smallest possible, Biggest possible, doesn’t matter? F: plaster and lath G: brick outer wall. Since this is not going to be our outer leaf, would it be a good idea to vent this wall, if possible? H: 2 layers of 5/8" drywall, Should we hang three layers? I'm worried about the new ceiling supporting the extra weight. I: New 2x4 steel studs for the outer leaf. Again, we need to build a new wall here to avoid penetrations through our outer shell. Would wood be better? Should these be built on the existing floor, or should we put down something to seal it first? J: 2 layers of 5/8" drywall. I know these should be on the other side of the stud, but I can't figure out a good way to get drywall up when you are right next to a wall. Ideas? K: Inner leaf ceiling joists. 2" x 6", 16" on center. Would 24" be better? How much of an air gap is appropriate here? We've got 12' of height to work with, so I'm willing to leave as much space as necessary. L: 3 layers of 1/2" drywall. Should I use 5/8", the other leaf uses 5/8" so I figured we should hang something different on this side. M: inner leaf 2x4 stud wall. 16" on center. Again, How much space is appropriate from here to the outer leaf? I can afford to leave a larger than normal air gap here as well. N: 3 layers of 1/2" drywall. O: New floor joists. How much space should we leave here? What kind and how much material should we use as flooring. We can't use concrete. I don't think the existing floor can support the weight. P: Rubber pucks to float the floor on. Q: existing floor beams R: existing flooring, definitely not airtight. over a 5 1/2' basement. Where should we insulate? Between which layers and how much should we use?

Oh man, I know the feeling you have -- your first detailed illustrations and a barrage of questions, now nervously awaiting a response and cringing at the possibilities! :lol: Well, nicely done. I think you've painted a great picture and communicated your questions really well. Beyond those kind words, I think I'll take a step back and see what some of the experts here (and some of the not-quite-experts-but-really-smart-anyway people) have to say about your difficult situation. If you have photographs to complement your illustration, that would be really helpful. You've described some conditions on that outer leaf that probably need some visual elaboration. Now if you'll excuse me, I need to get out of the office here so I can go home and kiss my garage, because it seems infinately more friendly to studio building than that challenging old building of yours! ;-) --Keith :mrgreen:

We are going to start construction in the live room on Sunday. I would be eternally grateful if someone were to take a look at the plans above and give me some advice. Thanks, Sam

Sam, I realize you're in a big hurry to start building stuff. However, having seen many projects on this forum rush into construction, only to have serious and sometimes irrepairable problems later, I have to go on record recommending that you not build anything until your plans are firm... And that will take time and patience.

sammy87 wrote:

We are going to start construction in the live room on Sunday. I would be eternally grateful if someone were to take a look at the plans above and give me some advice.

Great news! I have even beter news for though. You have already started. Good studio construction is 90% planning and 10% building. Andre

sharward wrote:

Sam, I realize you're in a big hurry to start building stuff. However, having seen many projects on this forum rush into construction, only to have serious and sometimes irrepairable problems later, I have to go on record recommending that you not build anything until your plans are firm... And that will take time and patience.

Unfortunately, we are under an enormous time crunch. If the room isn't built by January 1st, it won't be built at all. We don't have the luxury of time. I'm going to restate my questions and concerns and hope that someone responds to them by Sunday. 1. Can we safely ignore the existing stucture as an outer leaf to avoid the penetrations? If not, will venting help at all? 2. Should we suspend the new outer leaf ceiling from 2x4s or something more resilient. 3. How much space should we leave between the outer leaf and the existing structure? 4. Should the outer leaf wall be built on the existing floor or should new flooring be placed down first? 5. 2 or 3 layers of drywall on the outer leaf? Sam

Sam, I know all about time crunch; I'll try to cover all your q's tomorrow afternoon, before I go in for my last 12-hour night shift... Steve

OK, I'll start with your last set of questions, and add points I'm most concerned with as I think of them; also, I'll be around a few times a day starting Sunday afternoon and will try to keep a running commentary going til you're clear on all points. 1. Can we safely ignore the existing stucture as an outer leaf to avoid the penetrations? If not, will venting help at all? No, and no. This thread http://forum.studiotips.com/viewtopic.php?t=1198 shows the effect of a VERY vented leaf. Since you can't IGNORE the effect, you have to OVERCOMPENSATE for it or seal the existing and beef it up so it works as one of the main leaves; this doesn't sound practical in your case (pipes, missing sections, etc) 2. Should we suspend the new outer leaf ceiling from 2x4s or something more resilient. Before you do this you should REMOVE virtually ALL the old ceiling, this is creating a QUAD leaf which will hurt iso even more than a triple. Then, you will need at least three, and four if possible, layers of 5/8 gypsum for your outer ceiling leaf; those joists should have no problem with that much weight, you're adding about 11 PSF for 4 layers of 5/8. I'd hang your 2x4's down every 4 feet and pay particular attention to tight nailing. 2x6 sub-joists will be plenty to hang 4 layers of 5/8 on. BTW, most codes require metal framing for commercial space; do you plan permits and insurance, or are you financially suicidal? 3. How much space should we leave between the outer leaf and the existing structure? As little as possible without hard contact; the resulting resonance will have to be compensated with extra layers in both new leaves; minimum 3 layers (5/8" again) 4. Should the outer leaf wall be built on the existing floor or should new flooring be placed down first? Need more info on the floor first. And since the floor would have to happen first, we need to solve this as top priority - I need actual measurements of joist spacing, joist size, maximum UN-supported span of the floor, and details of the 5-1/2 foot basement(for dwarfs??!?) space - is it possible to add support columns under this floor (in basement) to improve span? Is the side wall of the basement continuous into the upstairs neighbors' space? Is it solid concrete, or brick, or?? Is there any other reason to soundproof your floor, other than flanking possibilities thru basement, up walls and into neighbor space? 5. 2 or 3 layers of drywall on the outer leaf? Covered earlier. Off to last night shift soon, I'll try to check on this tomorrow morning briefly and more as needed - please check thru your answers on each post to make sure you've answered EVERY question so we can keep from slowing your project down waiting for the next round... Steve BTW, looks like the minimum span for your live room inner ceiling would be about 19 feet - there is no way in hell you'll span that with 2x6's, no matter WHAT spacing. For 24" centers, you'll need 2x12 doug fir, Std & better to support 3 or 4 layers of 5/8" gypsum. For 16" centers, 2x10's would work. That much weight, resting on your inner walls, DEMANDS that there be serious support UNDER your floor at those points - Just calc'd basics for interior frame, 3 layers gyp, etc - it's looking like your floor at the perimeter would need to support around 260 pounds per square foot. This is immense. I'll re-check my calcs ASAP, but meanwhile don't even think of building this til we get things sorted out.

Steve, thanks for taking the time to help us with this project.

knightfly wrote:

Since you can't IGNORE the effect, you have to OVERCOMPENSATE for it or seal the existing and beef it up so it works as one of the main leaves; this doesn't sound practical in your case (pipes, missing sections, etc)

Do you mean overcompensate with mass? ie. adding as much drywall as possible to the new leafs? I'll get more details on the floor/basement construction at the studio tomorrow, and I'll post them here late afternoon. In the meantime, I'm going to start pulling plaster and lath off the ceiling. Thanks again, this is a great start. Sam