Tiny room advice.

Hi folks. My intension last year, was to build a brick practise-room for my bass and drums in the UK, but for various reasons, this is no longer possible. So, the long and short - I have a 200mm reinforced concrete base, for a wooden structure - 3.5m x 2.4m Obviously this is very small, and will seem even smaller once I get my Bass Rig and drum-kit in, but we can only work with what we have, eh? Now, as far as construction and attempted sound isolation go, I was intending to clad the outside with 22mm OBS (of which I would seal the gaps to make airtight) and then cover it with 12mm Shiplap cladding for aesthetics. On the inside leaf, I would have 3 or 4 layers of 12mm drywall (but only 2 on the ceiling with GG to compensate). Problem is, I dont know whether to use independant framework for each leaf, so I can totally decouple the exterior sheathing from the inside drywall. I know that this would give me a greater sound isolation, but I would lose valuble space (only have 2.4m to work with) and its obviously more work and money. On top of that, I worry that I would go to all the effort of constructing independant walls, only to find that the sound isolation wouldn't meet the requirements, and I end up having to use headphones after all, which defeats the purpose of using all that drywall etc. Does anyone have any comments or previous experience with this kind of dilemma? Am I on the right track as far as construciton goes, and will having the two leafs on seperate framwork much enough difference to be worth doing? Would adding extra drywall layers instead of seperate frame be a better use of resorces perhaps? Kind regards Steve

Hai steeve, That IS a tiny space indeed. How loud are you gonna be? (what's the purpose of the room) and how far away are your first neighbors? 'cos of the little space I would be tempted to advise one (staggered) stud frame. GB on the inside, wood on the outside. One superdoor. But, it all depends on the answers of my previous questions.

Hi I don't suppose acoustic drums would be worth playing in a room that small, so I will be using Roland V-drums and I would like (at the very least) to play it through the Drum Amp/Speaker set-up, at reasonable volume. At least I would be able to tweak the sound and roll off the volume/Bass if need be. I also play Bass, but I guess the volume of my playing should be compared to a loud home stereo, rather than a full band-rehearsal volume. The Neighbours enjoy sitting on their patio which is only 5 meters away. The area is also very quiet, with no traffic noise to help block out the noise from my studio. I don't mind losing an extra 200mm of the width of the room if building separate frames will make a large diff. But as I say, I'm worried that I would do the extra work, and lose the width, only to find that the sound isolation is not enough. Regards Steve

Problem is, I dont know whether to use independant framework for each leaf, so I can totally decouple the exterior sheathing from the inside drywall. I know that this would give me a greater sound isolation, but I would lose valuble space (only have 2.4m to work with) and its obviously more work and money.

Maybe you could consider building the inner-leaf walls inside-out. That will gain you a few inches on each side. - Stuart -

Hi guys. This is what I am thinking of building, as far as my sound isolation goes: 100m exterior framework, clad with OSB sheets, then shiplap cladding for aesthetics/weather protection. 50mm air gap, stuffed with either Rockwall or just Loft Insulation (I need to research this choice some more) 100mm interior frame clad with 3 layers of Drywall (2 layers on ceiling with GG between) 1) Assuming I build with good attention to detail, how much isolation I could reasonably expect? I would be playing Bass/ Drums at a reasonable volume (think loud home-stereo system). My neighbour is only 5-6 meters away, and there is no nearby traffic noise to help cover leakage from the studio. How likely is he to hear my playing ? 2) Secondly, this will give me interior dimensions of 1.8m x 3m x 2.1m high. I would need to squeeze in an electric Drum-kit and a bass rig, leaving hardly any space for Interior treatment. What would Bass and Drums sound like in a room this small? Even playing at the modest level I suggested above, would it sound so awful that I would resort to using headphones (in which case, I wouldn't need to bother about soundproofing?) Any pointers? Thanks guys.

Assuming I build with good attention to detail, how much isolation I could reasonably expect?

That's really hard to say, but with only one layer of OSB for your outer leaf, my guess would be "not very good". You also say that you will have a 50mm air gap, which is not good at all, yet your diagram shows an air gap more like 230mm (assuming your studs are 2x4), which is fine. I think I'd go with at least a couple of layers of drywall or something else massive on that outer leaf, and maybe another layer on the inner leaf too.

My neighbour is only 5-6 meters away, and there is no nearby traffic noise to help cover leakage from the studio. How likely is he to hear my playing ?

Once again, without real numbers to work with, it's really hard to say. You say you will be as loud as a "loud home-stereo system", but what does that mean? some folks would consider 85 dB to be "loud", while others wouldn't call it "loud" unless it hit 105 dB. That's a huge difference in terms of power and energy. If you only play at 85 dB then you might be OK. But if you play at 115 dB, then you won't be so fine.

My neighbour is only 5-6 meters away, and there is no nearby traffic noise to help cover leakage from the studio. How likely is he to hear my playing ?

Once again, that depends on many factors, not the least of which is how sensitive your neighbor is. Some folks don't care if you stick a ghetto blaster in their window, others will call the cops if your MP3 player ear buds are too loud! It's very subjective.

...leaving hardly any space for Interior treatment.

So build it "inside out" then, like I said before! That will gain you a few inches in each direction, sine your treatment will be mostly IN the walls, not ON the walls.

What would Bass and Drums sound like in a room this small?

With no treatment? Pretty lousy, I'd say. With treatment? A bit better.

Hi Soundman, thanks for your comments. I realise that when quoting the distance between the inner and outer leaves, I was stating the gap between the frames, rather than from the Drywall to OSB. The gap would indeed be approx 230-250mm. From your comments, its sounds like I will need far more mass to my layers than I initially thought. If, as you say, I should be looking at (at least) 2 layers of OBS on exterior and 4 layers of Drywall on interior, I will need to start thinking hard about the cost of materials. I have two concerns, of course…. not only if the sound isolation will be up-to my requirements, but also, if the room sounds truly awful, even with treatment, I'll only go back to headphones which defeats the whole point of extra mass/ decoupled layers. I think I will need to invest in a sound-level meter, so I can give some numbers to my requirements. Thanks for you comments - certainly given me something to think about!! Regards

Hi folks. I've measured my Bass Guitar and V-drums through a Drum Amp, using C-weighting FAST settings. While its difficult to get an accurate reading as the needle jumps all over the place, they generally seem to be around 95db, with a couple a peaks to 102db here and there. This was with the sound-level meter within 1m of the Amps. With rolling of the Bass EQ and lowering the gain a little, I guess I can stay consistently under 98db. I have to say, this shocked me as I didn't perceive my playing to be that loud? I've also been researching staggered-stud walls as I have a tiny room to start with, and even loosing an additional 200mm with make things . Initially, I was enthusiastic to see that a staggered stud wall with 2 layers of Drywall and a layer of OSB either side could yield a STC of approx 56…….then I read that STC means nothing and you should only be concerned with the TL at lower frequencies. The TL rating of the above at 63hz is only 20. So what does this mean in realistic terms ? Am I correct in thinking that 98db inside the room, will lose 21db when passing though the wall, leaving a perceived volume of 77db on the outside? If so, that is not good news, as previously stated, my neighbour sits on his patio 5m away. My aim was to reduce the leakage to almost nothing so as not to cause them any nuisance. Is this do-able? I have the feeling the answer is going to be no, certainly not with a staggered studwall assembly with a few layers of Drywall. I feel I have 3 options, but my choice is dependant on how much of the 95db I can stop with my limited space and resources. OPTION 1: Spend the extra money and sacrifice what little of my 2.4m width I have, in constructing a decoupled double-wall assembly in an attempt to reduce 95db of bass down to near nothing on the outside. To give me an idea if this option is even, well, an option…..will the following method of construction get close to that kind of isolation? Exterior wall with 2 layers of OSB ……230mm airgap ……. Interior wall with 3 layers of Drywall. OPTION 2: Create a staggered-stud assembly with an aim creating a modest amount of isolation, and only using the studio when I know the neighbours will not be outside or have their windows open, like on cold evenings or wet weekends etc… At other times I would use headphones. Not ideal, as I wanted to get away from headphones… but the benefits would be more room inside, and it would obviously cost less to build. OPTION 3: If I am totally deluded about how much bass a few layers of drywall and OSB can stop, then perhaps I should not bother with anything more than a single wall assembly and resort to headphone use permanently. At least I will save money, space and time building. Anyway - perhaps if someone with build experience could set me straight on my expectations, I would be so very grateful to you. Many thanks. Steve

The TL rating of the above at 63hz is only 20. So what does this mean in realistic terms ? Am I correct in thinking that 98db inside the room, will lose 21db when passing though the wall, leaving a perceived volume of 77db on the outside?

Well, not really. What the "TL 20 at 63 Hz." figure means is that for the single frequency band centered on 63 Hz, the transmission loss is 20 dB. So you'd need to use a spectrum analyzer to see what your level is AT 63 HERTZ, and then subtract 20 from that. But you are talking about only ONE band here: the 63 Hz. band. The "98 dB inside the room" refers to something entirely different: it refers to the sum total of ALL of the frequency bands, of which the 63 Hz band is just one. The energy in the 63 Hz band will be somewhat less than the 98 dB level (depending on what kind of music you play). In other words, 98 dB is all bands added together, and 63 Hz is just one of those, so it has to be much less than 98 in that band alone. So, unless you did that measurement with a single large kick drum tuned to 63 Hz, and you were really pounding the living daylights out of it with all your might (using a sledgehammer, maybe?) then I doubt that you have 98 dB of energy just in your 63 Hz band! :) If you were playing average pop music, then probably there wasn't much more than 60 or maybe 70 dB in the 63 Hz band. So if your wall is going to get you 20 dB of isolation at 63 Hz, that would give you around 40 to 50 dB on the other side of the wall, in that specific band. That's reasonable, actually. Could be better, but not bad. And since you are getting 20 dB at 63 Hz, which is about the hardest band to isolate anyway, you should be getting much more than that at higher frequencies. So your wall overall is going to isolate much better than you project, and the level on the other side will be substantially less than 77 dB.

If so, that is not good news, as previously stated, my neighbour sits on his patio 5m away. My aim was to reduce the leakage to almost nothing so as not to cause them any nuisance. Is this do-able?

Yup! Should be possible. I'll answer your other questions later, but I have to run for a meeting now.

I've measured my Bass Guitar and V-drums through a Drum Amp, using C-weighting FAST settings. While its difficult to get an accurate reading as the needle jumps all over the place, they generally seem to be around 95db, with a couple a peaks to 102db here and there. This was with the sound-level meter within 1m of the Amps. With rolling of the Bass EQ and lowering the gain a little, I guess I can stay consistently under 98db. I have to say, this shocked me as I didn't perceive my playing to be that loud?

That sounds about right to me. Around 100 dB(C) at one meter is what I'd expect from an enthusiastic bass player with a good amp. Don't be surprised about your level: Must musicians are! I teach a basic sound systems course for musicians, and most musicians actually are surprised at the levels that they play at, when you show them the meter. And they are even more surprised when you show them the OSHA exposure tables! At an average level of 100 dB, you have 60 minutes until your hearing suffers irreversible damage. In simple terms: Play for an hour and you go partially deaf. I'm not trying to be funny with that: just quoting simple real-world figures. Most musicians are shocked to learn this. At 105 dB you have 30 minutes. The big surprise for drummers is that at 110 dB your inner ear suffers irreversibly damage in 15 minutes. I never met a drummer who didn't hit 110 dB just warming up, with one hand tied behind his back! Most drummers can easily keep up a level of 115 dB without trying too hard, which sentences their ears to a life expectancy of about 7 minutes, before they start dying. And at typical rock concert levels (120 dB) you get irreversible hearing damage in 3 minutes. That "damage" in all of the above cases is estimated to be a 34 dB temporary hearing loss across some portion of the spectrum, with 90% recovery probable after 12 hours, provided that there is no more exposure to loud sounds during that time period. The most common sign that this loss has occurred is known as "tinnitus" medically, and commonly referred to as "ringing" in the ears shortly after the loud noise stops. If you hear that, then it's too late. No matter which way you look at it, these figures are scary. Many musicians already have some form of hearing loss, and don't even realize it. I saw a summary of a study done on a symphony orchestra a while back, where every single violin player turned out to have substantial permanent hearing loss in their left ears. And of course, the natural response to suffering from partial hearing loss is to compensate by turning up the volume... Anyway, I mentioned the above so that you don't feel alone at being shocked by the level you normally play at! You are in good company. So yeah, your numbers sound about right. Scary, but right.

Exterior wall with 2 layers of OSB ……230mm airgap ……. Interior wall with 3 layers of Drywall.

If you build it right, that should give you an STC rating of somewhere in the mid to high 60s, which is pretty good. However, that doesn't mean that your 100 dB level is going to be reduced to less than 35 dB outside, since it doesn't really work like that. STC rating doesn't actually tell you much about the low end of the spectrum, which is precisely where your bass amp puts out the most energy, and precisely where good isolation is hardest to achieve. However, you probably could expect to get it down to the 50s, which hopefully will be acceptable to your neighbors. That would improve even more if you were to use Green Glue between the layers of drywall. Green Glue does good things to the low end of the spectrum. It isn't cheap, but is well worth the price. So, yeah, I think I'd go with something like your "Option #1", since it should do what you want it to do, provided that you design it and build it right. Definitely build the two leaves of your wall on independent stud frames, put as much mass as you can afford into each leaf, keep the air gap as large as possible (230 mm is great), fill that air gap totally with isolation, seal everything totally air tight, then seal it again, and you should be fine. What I'd maybe change in your rough plan is to replace the OSB with something even denser and more massive (maybe thick fiber-cement board, or thick plywood, or both, or something like that), and specify that the drywall is 5/8 drywall, not thinner than that. Hope that helps somewhat! - Stuart -

Hi folks, I am still working on the design for my tiny-room and have a question. Asume the following scenario: 1) Room in a room design, and the inner-left totally decoupled from the outer-leaf with the exception of the common concrete base. 2) Inner leaf is an inside-out wall with two layers of sound-block drywall, and two tubes of GG per 8x4sheet. 3) 4 inch air-gap filled with fluffy insulation to deaden the cavity, seperates the the two leafs. 4) Outer-leaf is just 18mm wooden shiplap-cladding and therefore not air-tight. Obviously the isolation of this room isn't going to be anything great as the outer-leaf has little mass and isn't airtight. Therefore, is it even worth having the two layers of sound-block and GG on the inner leaf. The same could be asked about whether it is even worth having the de-coupled walls ? Would the multiple layers and green glue still make a noticeable difference and be worth doing even with the poor outer-leaf ? Sorry for asking, but I am just trying to gather enough info so I can make a choice about what kind of construction would work best for me, given time/money etc..... Thanks Steve

Steve - as the shiplap isn't airtight and sealed I wouldn't treat it as a leaf - I'd add 1 layer of soundblock to the outer wall - inside - then I'd add the other layer to the inside/out inner wall. I'd put insulation between the inner and outer wall only, no GG involved. That's what I did with Left Bank and it worked well. http://johnlsayers.com/Studio/Mainpage/MP-Leftbank.htm

Hi Mr Sayers, thank-you very much for taking the time to read my posts!!! I'm a bit unsure of your advice….. So I have drawn how I have interpreted it. As my room is so small, I have needed to place my two studwalls very close together. This means I will only have a 1 inch gap between the layers of soundblock - unless I have misunderstood your words? Is this how I should build it ? Many thanks! Steve

the insulation goes between the soundblock - yup - it's only 1" but they are not connected which is the main factor. For ease of construction I'd put the double layer on the outer wall if you intend to use two layers.

Hi folks, following on from Johns expert advice, I have started work on the studio construction. I have a tight budget, so I have decided to construct the exterior walls only, as a single leaf construction. I wil move my electric drums inside and see how it sounds/how much TL it suffers. If it performs really bad (and money is available) I can then add the second leaf (inside-out walls) to increase the isolation. If, however, it sounds reasonable, I could choose to leave it as a single leaf and just have to live with keeping playing volumes very low. lol. I'm aware this isn't a great way of doing things, but you can't get materials for free, and this is only a hobby-room and not a business. Here is my work so far: This is a diagram of my intended construction. I will use 1" spacer batons so the shiplap cladding is spaced away from the permable-barrier. This will allow air to circulate and prevent dampness. On the inside, I was going to clad with 9mm Ply to increase rigidity, and then use 12.5m SoundCheck plasterboard to provide mass. Question 1: I was intending to use pink fluffy insulation inbetween the exterior studwork, sandwiched between the permable-barrier and the layer of 9mm ply, but I thought people used this to deaden the cavity created by two leaves? As this part of the assembly is not a cavity between two airtight leaves, would it be beneifical to use Rockwool slabs instead? Would using these provide a greater degree of sound-isolation? Question 2: Should I forget adding the 9mm ply inside? The Ply would cost as much as a second layer of 12.5mm SoundCheck, but I would be decreasing ridigity in exchange for an increase in isolation. Regards Steeeve

Hi Steve, looks like you've made a great start! I now know how quickly your budget can get eaten up, but if you can stretch it, I'm sure you'll be much more impressed with your room if you can make it with two leaves. I know it made a huge difference once I put up my inner leaf- one day a few weeks back, it rained really hard, and I could hardly hear it compared to when I only had the first leaf done! This is no scientific test I know, but it made me feel that all this money, time and effort was going towards something I can be proud of. BTW my budget of £500 has gone completely out of the window- god knows how much it is now! I just keep telling myself (and my fiancee) it's worth it... I can't really give you any expert advise, but personally, I would go for two layers of plasterboard and drop the ply. If you do think you'll want to add an inner leaf, you may want to think about putting the plasterboard nearer the permeable barrier (in between the stud work, rather than over it), so you can use the existing stud work as space to add more fluffy stuff. More work, but perhaps worth considering.