new studio build from ground up

just getting the room right is complex enough in itself before the building starts!

tell me about it! I've been working and re-working my design for over a year now, and still not happy with it. Read André's signature to get the idea: It says something like "building a studio is 90% design, 10% construction". And he's being conservative with those numbers! The problem is, the more that I learn about it, the more I realize that I don't yet know enough! So I keep on learning, and keep on tweaking the design... Welcome to the club! :)

i found some sliding doors in the online model site but i couldnt scale them into my design

Select all of the parts of that sliding door, and make it into a single component. Now press "s" (for "scale") You'll get an outline around the object with little green cubes on it in some places. Move the cubes to scale the object in different directions...

also the walls are squear at the moment obviously the apex would have to be built on the sides to bring them to the roof beams.

Not necessarily! Your leaves don't have to be parallel. Your roof can be at one angle while your ceiling is at another angle. You could just put a flat ceiling across those rooms if you want.

the rooms need to be seperate from themselves, so i cannot tie both rooms timber sections together (i hope im right on this) so they need to be seperated.

Absolutely correct! But it looks like you are on the right track. You just need to separate the frames between the two rooms.

i have left a 50mm cavity between the 2 layers of 15mm gypsum board and the blockwork,

50mm isn't very much. That's only 2 inches, and the normal recommendation is for at least 4 inches (100mm / 10cm), or more if you can afford the space. The resonant frequency of the cavity will be too high with such a small air gap.

the framing is 50x75,

That sounds like roughly 2x3 studs (but not exactly?), which probably isn't enough, especially for the ceiling joists (which you didn't show yet). The framing has to support a really heavy load, so you want at least 2x4 framing, probably. Your ceiling joists will depend on the span and the load. Use a span calculator to find out what dimensions you need and/or check with a structural engineer / builder.

question: on the outside of the frame closest to the wall, could i use 2 layers of 15mm concrete board instead of gypsum?

Yep! I guess you are talking about the stuff called "fiber cement board" where I live? Yes, you can use that stuff, and it is about twice as dense as drywall, which means you can make it thinner and still get the same degree of isolation. But it is also more expensive. As long as you don't mind the expense, (and building inside a cloud of cement dust!), then its fine.

and just have the two layers of gypsum on the inside?

What do you mean by "on the inside"? If you put fiber cement board on the outside of your frames, then you do not need anything on the inside of the frames! You already have two leaves.

would the outer concrete board be better as its more dense?

Yep! Denser is better. But more expensive...

also is there prehaps a better orientation for laying out the rooms? i can only see the rooms the one way as its not something i have done before.

You seem to be on the right track, but I don't think that you ave enough space for the sliding glass doors. Maybe a simple hinged door with glass in it would be better. With those sliding glass doors, you don't have enough space for your speaker soffits. Also, the angled areas on the front of your control room (CR) don't need to be done like that. You can just make those 90° angles, then build your soffits inside that. You could also angle two of the inner-leaf walls of your live room (LR), for better acoustics.

i did think about having the room so that im not facing the long way down the room.

Not a good idea! You really should have your speakers firing down the longest axis of the room, rather than across the short axis, for a small room. You want the rear wall as far behind you as you can get it. But don't forget to check your room ratios, to make sure you are far away from all "bad" ratios, and reasonably close to a "good" one.

and also because im sure i will need to spereate the room frames anyway.

Yep! :) - Stuart -

thanks for the quick reply stuart.

also the walls are squear at the moment obviously the apex would have to be built on the sides to bring them to the roof beams. Not necessarily! Your leaves don't have to be parallel. Your roof can be at one angle while your ceiling is at another angle. You could just put a flat ceiling across those rooms if you want.

what i meant was the external block work walls, where the roof joins on the centre top beam, i would still need to bring the blocks upto this point in my external walls. the framing is 2x3 reason being that the rockwool that most seem to use is 3" thick. ok well the concrete board on the framing is great news, i will go for that, regarding the inside gypsum boards, i thought that as well as two on the outside of theframe you also had to put some on the inside of the frame when building an inside out wall. however as i can get the boards cheaply i will go for the concrete boards for the inside out wall. i have attached a picture of what i mean stuart hope this helps. with the inner walls covered in plasterboard i can get them skimmed prior to painting them. i thought about making some wall diffusor boxes and clouds for the celing afterwards. i will do the scale thing with the door this afternoon and sperate the room frames, also change the framing and cvity distance and re measure things up again. the celing joists will be 2x4 stuart, sorry i hadnt got to the roof section yet, i needed some clarification on the basics first, like my old carpentry teacher used to tell me every day, measure twice cut once im using the same ethos here with this, once the plan has been checked for everything then i can proceed, until then check check and check again.

regarding the inside gypsum boards, i thought that as well as two on the outside of theframe you also had to put some on the inside of the frame when building an inside out wall.

NOPE! That would make a three-leaf wall, which is something you do not want. (And isn't necessary in any case, for your situation). You already have concrete blocks for one leaf. You only need one other leaf, which will be either the fiber-cement board or the drywall, but NOT both. Two-leaves, only, ever. Never one, never three. Just two. (Unless you have some really unusual issues!). The purpose of building inside-out is so that you can use the space between the studs for room TREATMENT. Acoustic treatment is deep, and has to be hung on the walls anyway. But if you build inside out, then it can go in the space BETWEEN the studs, instead of on top of the drywall. But you still have to fill the wall cavity with insulation. The cavity is the 4" gap between your concrete blocks and your drywall. Regardless of what you do inside the room itself for treatment, you need that insulation in the cavity as part of the MSM system. Also, don't forget to seal those concrete blocks before you start building! They are porous, which isn't good. You need to seal that. Stuck, plaster, paint... anything that seals well will work fine.

the framing is 2x3 reason being that the rockwool that most seem to use is 3" thick.

Yeah, but that framing has to support a LOT of weight! Add up the weight of all of that fiber-cement board, and all of the ceiling drywall, and all of the framing, and all of the caulking, and all of the insulation, and all of the screws / nails / Green Glue, and all of the electrics, and all of the lights, and all of the acoustic treatment, and all of the... OK, I think you get the picture. Those walls have to support thousands of pounds of mass. I'm not sure that 2x3 studs is enough to do that, especially if you are going to use 2x4's on the ceiling. Code probably doesn't even allow that. You might want to check with a builder or engineer.

with the inner walls covered in plasterboard i can get them skimmed prior to painting them.

With inside-out construction, there is no plasterboard! Nothing to paint. either build slot resonators over the walls, or just cover them with cloth if you only plan to use absorption. Or use the stud space for panel traps, or whatever else your room needs. But no plasterboard, and no paint. - Stuart -

well saying i did put the other layers of gypsum board on the inside, would it really make that much difference to the room stuart? im only asking because on the odd occassion i may crank it right up in there, and if i get larger speakers in there for the odd "pink floyd" eardrum shattering moment when i find insperation will the extra internal boards help with sound isolation ? im revising the plans for 2x4 framing and will have that done for later on. im still reading up and still learning, and yes i also like andre's quote about the 90% design to 10% construction its quite apt in this case! the ceiling will have two layers og 15mm gypsum and an internal of rockwool, however the "attic" cavity will be blown in with shredded isolation material, so the whole roof cavity will have a good 6-8 inches of insulation material on top of the rockwool.

pk1 wrote:

well saying i did put the other layers of gypsum board on the inside, would it really make that much difference to the room stuart?

If you are meaning all the gypsum in one layer, then yes it waill make a big difference, as in improvement. Andre

well saying i did put the other layers of gypsum board on the inside ... will the extra internal boards help with sound isolation ?

Actually, they will REDUCE your isolation! Stop looking at me like I'm nuts! That might sound illogical and counter-intuitive, and it is, but nevertheless, it is true: Adding a third leaf to a two-leaf wall really can reduce isolation in the low end of the spectrum. "Low end of the spectrum" is the place where kick drums, toms, bass guitars, the lowest octaves on keyboards, some percussion, and other Pink Floyd favorite tones live. The reason for this is kind of complex, but basically your two-leaf wall is a tuned filter. It pass sound through at the frequency it is tuned to, and blocks sound at all other frequencies (with various degrees of success). If you design and build it right, your wall will be tuned to have a resonant frequency that is LOWER than the bottom end of the audible spectrum. At its resonant frequency that wall will be a really lousy isolator, and will in fact amplify and assist sound through it, at that frequency. At all higher frequencies, it gets progressively better at filtering (isolating). At twice the resonant frequency, it already does a reasonable job of isolating, and it just gets better and better as you move up the scale from there. All well and good so far, right? The wall is tuned low enough that it isolates all the frequencies that we humans can hear and are concerned about. BUT! If you add a THIRD leaf to it (where a leaf is just a massive surface separated by an air gap), then what you ave done is to RE-TUNE the wall, such that the resonant frequency is now much higher than it was before! So now, the frequency band where the wall is a really lousy isolator has moved up into the range where we humans CAN hear them, and thus your wall becomes a bad isolator at low frequencies. Pink Floyd is now thumping in your neighbor's living room, as well as in your studio... You can compensate for this "three-leaf effect" by adding even more mass to the leaves of your wall, and also by increasing the air gaps. That will re-tune the wall to a lower frequency once again. But at the expense of more mass (=more money) and reducing the usable floor space inside your room. You can do that if you want, but why would you??? :) If you really are concerned about being "too loud", then it would be much, MUCH better to put that same drywall on the other side of the studs, right along with the fiber-cement board, so that you get back to a two-leaf wall again: The extra mass on the second leaf would be very beneficial, and would greatly improve your isolation. But if you make it into a third leaf, it will do the opposite. Maybe this graph might give you a better idea of the issue: The line marked "mass law" is the theoretical best isolation that you can get from a single-leaf wall, which is basically just a solid lump of mass (such as your existing concrete brick wall. The line marked "double panel" is what you get from a 2-leaf wall, and the line marked "triple panel" is what you get from a 3-leaf wall. What you will notice on that graph is that it is really hard to isolate low frequencies (left hand side of the graph) no matter what you do! But a 2-leaf does a better job than a single-leaf provided that you tune the resonant frequency low enough, and it also does a better job than a 3-leaf. This is not intuitive, but is obvious when you see the graph. At high frequencies a 3-leaf is better than a 2-leaf, but it doesn't matter since a 2-leaf is already pretty damn good by the time you get up to the frequencies where it makes a difference. However at the lower end of the spectrum, a 3-leaf is always worse than a 2-leaf, all other factors being equal. So you really do not want to put that drywall on the outside of the studs if you plan on playing Pink Floyd in there! It would be good if all you ever plan to do is have piccolo solos in there, but any music with considerable low frequency content is going to be worse off with a 3-leaf. Having said all that, what you really should do is see just how good your existing isolation is, by measuring real sound in your real room with a real sound level meter. Play your favorite Pink Floyd at the loudest level you ever expect to produce, then measure that inside the room, then measure it outside the room in many locations, both inside and outside the house. Note down all the readings on the meter at all of those locations, and circle the HIGHEST reading. That is your worse-case. Now progressively turn down the volume inside the room until you can no longer detect any sound at all, at ALL of those locations. In other words, turn it down a bit and measure again, then turn it down some more and measure again. Note down the reading on the meter at all of the locations, at the level where you cannot hear the music any more, and circle the LOWEST reading. (Do this test late at night when everyone is asleep, and the ambient level is at its lowest.) OK, so now you have three numbers: 1) The level inside the room with Floyd belting out full blast, 2) The highest level outside your room with Floyd belting out full blast 3) The target level for perfect isolation, with Floyd whimpering along vaguely. Subtract 2 from 1: This is how much isolation you have right now. Subtract 3 from 2: This is how much additional isolation you need, in order to keep the cops away from your front door. :) With those numbers in hand, you can figure out the best design and construction method to attain the target level of isolation. - Stuart -

If are meaning all the gypsum in one layer, then yes it waill make a big difference, as in improvement.

He's talking about putting it on the other side of the studs, André. As in 3-leaf... :shock: - Stuart -

hi andre. what i mean is as per my picture above, the blockwork wall, an insulated cavity as per stuarts info, two sheets of 15mm concrete fibre board, 2x4 framing with rockwool filled voids, then two internal layers of 15mm gypsumboard. i know it may be overkill but surely because of the possibility of future levels being loud, also having drumkits in there being beat the crap out of, this would improve the soundproofing? i would have the walls skimmed out, this being something i would personally want to do, making it clean and neat, i can then paint the walls. also make a load of panels to go onto the walls, clouds for the ceiling, also make panels for the rear wall. the lights would be ceiling mount lights, the gu10 240v led flushmount lights that recess into the ceiling, these would have fire caps above them, these are fire retardant cones that cover the lights in the cavity, so that if there is a spark or fire they suddenly shroud the light fixture and prevent fire, i used them in my house when i fitted new lighting.

ok i get you andre, stuart it would have been good to have put the boards on the inside also simply because i wanted to skim and paint in there. ok say i do it differently then, on the cavity side of the frame i cover that with a damp/rot/mold proof memberane, fill the voids with rockwool and then have 2 layers of 15mm gypsum on the inside of the framing, would that be a good option? with regards to the blockwork, i was watching a programme on tv the other day called "grand designs" on this build the owner a commercial architect had his building skimmed in a special facade paint, this blocks water and dirt and basically keeps itself clean. here is the link to the manufacturers site. http://www.stoshop.co.uk/products/item/stolotusan-color i can then paint the exterior of the build in this which would then seal the face of the blocks, if need be i can get one of thier other paints for the inner block walls, thereby sealing the face and insides.

the lights would be ceiling mount lights ... that recess into the ceiling,

Careful!!!! If you do that, you will have to cut holes in your inner-leaf. In order for the MSM system to work properly, each leaf should be one solid sheet of mass, with no holes in it. Cutting a hole, or even a small crack under the wall, is enough to damage the isolation. It will cost you many decibels of isolation. You can still do recessed lighting, of course, but you have to make up for the hole by building mass around the back of the light fixture (to the same level as the drywall was giving you), and sealing it air tight. Both leaves must be sealed hermetically airtight, for optimum performance. So any place you are planning to cut any kind of hole, you need to think about that carefully to plan how you are going to seal it up again, and make up for the lost mass. The same applies to things like electrical sockets, light switches, microphone patch boxes, etc. The best way to avoid those issues is to surface mount all of these, on top of the drywall surface, without penetrating at all. Use surface mount cable ducts, too, so even the wires don't penetrate the drywall.

it would have been good to have put the boards on the inside also simply because i wanted to skim and paint in there.

Well, you don't HAVE to build the wall inside out! Instead of putting all the mass on the cavity side of the studs, you can put it all on the room-side of the studs instead. In that case, you can paint and decorate to your heart's content. And then you can cover most of it with the acoustic treatment that you will undoubtedly need.

on this build the owner a commercial architect had his building skimmed in a special facade paint, this blocks water and dirt and basically keeps itself clean.

As long as it seals the concrete surface, and will stay that way forever, then it will work. That stuff you linked to sounds like it will do the trick for sure, but you can probably get something less fancy and a bit cheaper for the wall face inside the cavity: nobody will ever see it in there once the wall is up, so it can be whatever you want that does the job. - Stuart -

hi stuart the external paint is used on commercial buildings and after speaking with them it is perfect for what i want, they also do a cheaper coating for the internal blockwork, so i am all set to use their products, the face wall (outside) will be rendered then coated with this nanotech paint. im hoping to speak with my building inspector friend this week and double check things with him and then i can get the footings and pad booked to be done as the weather here is great at the moment and for the foreseeable future. then its just finishing the internals in sketchup. this week i will finish the adjusted framing and ancillaries in sketchup and upload it again, if thats ok i will then move onto the panels etc that will be needed in there using johns small studio in 3d file as a baseline to work from., if we can agree on a layout for that its just the ceiling then the roof to sort out. and i can then get the rest of what i need ordered. even if i just get the pad and blockwork done first its something, the roof is a given really in how i want it, so that can be done also, and the whole thing made watertight, at least doing the internals will be much easier then and if the plans still need adjusting its not an issue with weather then. i have a schedule laid out i just have to have 5 mins peace here to get it done now!

Soundman2020 wrote:

Maybe this graph might give you a better idea of the issue:

Not preserved: 2-leaf-vs-3-leaf-700pix.jpg

Only seems fair that we should provide a link back to items like these graphics so others can get access to the same information that we have had access to. Is that from Techniques to Increase Sound Insulation of Building Elements: Wyle WR 73-5R ? I can't remember ;)

Is that from Techniques to Increase Sound Insulation of Building Elements: Wyle WR 73-5R ?

Yup! It sure is. :) There's a link on the forum somewhere to the entire paper, but I couldn't find it... - Stuart -

Soundman2020 wrote:

There's a link on the forum somewhere to the entire paper, but I couldn't find it...

Here is the link to the the file Sharpe, Benjamin; 1973: A Study of Techniques to Increase the Sound Insulation of Building Elements; Wyle WR 73 5R. There should be enough enough information in this post to assure hits for anyone using the search function looking for it. Seal everything, and no triple leaf. The studio builder's coat of arms.

many thanks for all the help guys, i have done a lot of reading the past few days before i have started on the framing again. the framing is coming along fine and its almost finished, the ceiling will be made the same way, im hoping that the finished design is ok. i have switched back to the inside out wall and im happy with that, also im going to do some of the strip wood sections that other builds have, im just wondering , is it ok for me to use something like 1/2" layerd ply, rip it down into strips , sand and stain/seal it then use those on the interior walls? some of the ply i can get has a nice finished surface and will come out very nicely. i should have the finshed layout done over the next day or so and then i will upload it to the thread. also forgot to ask, the 100mm/4" cavity between the inner block and the boards, i can also fill this with any insulation material or is it better to use rockwool again in there?

also im going to do some of the strip wood sections that other builds have, im just wondering , is it ok for me to use something like 1/2" layerd ply, rip it down into strips , sand and stain/seal it then use those on the interior walls? some of the ply i can get has a nice finished surface and will come out very nicely.

Ummm... If I understand what you are talking about, then those are not just "strip wood sections"!!!!! They are carefully designed and built slot resonator walls, where each dimension accomplishes something specific. You can't just slap up any old piece of wood on a frame and expect it to work!!! You need to follow the exact dimensions and instructions that John has provided, and you need to do it fairly accurately. Search the forum for "slot wall" and "slot resonator", to find out how to do it right.

also forgot to ask, the 100mm/4" cavity between the inner block and the boards, i can also fill this with any insulation material or is it better to use rockwool again in there?

Not really! You can use any SUITABLE insulation material, that has the necessary acoustic properties. That implies things like it being open cell insulation (never closed cell), having the right density and gas flow resistance, etc. Once again, you can't just throw any old stuff in there and expect it to work. I'm wondering if you aren't maybe running too fast with this build: You are already into framing but still seem to have basic misunderstandings like the above... Maybe you should slow down a bit on the build, and do a bit more research, planning and design. I get the impression you might be rushing ahead without really understanding what you are doing, and that's not a good way to build a studio! You asked these two things (fortunately!), but who knows what you might NOT have asked, and already gone wrong? - Stuart -

hi stuart. i have a good understanding of various elements of the build, and those im not clear on i am currently reading up on. the biggest problem which is something touched on before and understandably why you ask members to be so concise in thier posts is the fact i have to wade through so many threads in the forums before i find just one or two that bear relation and have a finished topic with the info i need. i dont know how you guys manage to go through that lot all the time!!! im still working on my own design, im wondering if prehaps john may have a design suggestion or layout suggestion? i have done a search on slot wall/ resonators, and there are once again so many threads that need to be read through, im going to have a read through rod's book tomorrow while i have some down time again.

Do you also have the "MHoA" ("Master Handbook of Acoustics", by F. Alton Everest)? If not, it sure is worth getting it. It's the "Bible" of basic acoustic theory, and will probably help you lots with designing your room and your treatment. Rod is more practical, and tries not to delve too deeply into theory in his book, but the MHoA goes much deeper. On the other hand, you won't find the down-to-earth practical construction stuff in MHoA: you need Rod's book for that. Between the two of them, you have a really solid basis. (I was going to say that you have a really "sound" basis, but the pun is rather tacky! :) ) - Stuart -

just had the get on with it or else lecture from the wife... :cop: :cop: :cop: :cop:

pk1 wrote:

just had the get on with it or else lecture from the wife...

Have her read my signature line. It refers to time involved. You have gotten on with it! :yahoo: Andre

building inspector comes tomorrow, check plans and layout of pad, building and if its a go then i can get the pad and shell built as soon as possible!

plans passed scrutinisation today, im below the max square meters allowed so its all go, i just have to wait for a confirmation letter and all is good. this means the footings, pad and blockwork/roof can be built.

Congratulations! Great milestone! So now the easy part starts... :) - Stuart -

yes i agree with you on that stuart! its what happens inside thats daunting me! i will have some groundwork to do shorlty and i will start taking pics and adding to the thread when i do, once i start perhaps the thread should move the thread to the construction section. onwards and upwards!

WOW!!!!!!!!!!!!!!! my god it has been some time since i was able to post in here ;) Well things didnt go to plan and the plans had to change and then there were other issues along with starting a new business. Over the past two weeks things seriously moved along though!! The plans changed again and i had to go slightly smaller and i dont have an acoustic room anymore. This is not an issue for me as i can make a foldable screen for vocals and that will do. I am going to try and get the new plan done in sketchup today, but it has been a while since using sketchup so its basics and relearning again!! Hopefully i will haveit done by the end of the day. I will add some photos later on to show where i am, its just the shell with no roof at the moment, however i should have the roof done by the weekend. Looking forward to getting on with things now, almost as much as the wife!!! you see i have now got equipment under the stairs in the hallway, the spare rooms, the conservatory, my office and its now spilling into the main living room.... not going down very well with wifey i can tell you. On the plus sde she is really happy that i am finally getting my studio room. More to follow and probably a few mundane questions relating to sketch up and framing i dare say!! Thanks