John Sayers' Recording Studio Design Forum

Hey everyone,

I need your help. Ok so after doing some tests on my newly built live room, I am not happy. I was stupid to think I would get a decent result with what I built in the first place so yes I am quite the idiot in this case. But please if you can all be kind enough to look past that I have been so silly I really need help to fix it , Ill tare down walls if I have to (the ones I can anyway) So Im looking for anyone who would be kind enough to advise me on how to solve the issue. I'm busy drawing up some detailed sketchup models of the whole thing so anyone who is willing to help me can understand the problem fully. I will post up some illustrations as well.

The basics:

The studio consists of two rooms (live and control) located on the first floor of a office building. The surrounding space is offices. All the walls are a standard drywall (single board-studs-single board, with insulation) no decoupling. The floor is concrete slab. The ceiling is suspended from the slab above. The cavity between the ceiling and slab above is about 1 meter.

What kind of Isolation I am looking for:

The studio will only function at night and on weekends when the surrounding offices are unoccupied. So to be honest I don't care how much noise gets out. I have no neighbors that I will be bothering while I am working. Also so far Ive checked that even with the monitors blasting there isnt much noise past the front door to the lift lobby anyway, so the only offices that are affected are the ones literally right next to me (I will include a floor plan to illustrate). What does matter to me is the noise that gets in. Particularly in the live room. I want the live room as quiet as I can get it. I am happy with the current isolation of the control room since the surrounding environment is pretty quiet already. But when I set my mic gain up to a decent level I am not happy with the isolation of the live room so far.

The dreaded triple leaf:

Before learning how bad this is, I went and built a triple leaf system in between the live and control room. I think?

I was looking into just leaving the rooms as they are and then building a new room inside the live room (room in a room). New walls right round the inside decoupled from the floor and existing walls, supporting a second ceiling which will obviously not touch the existing suspended ceiling above. And double door. But I am scared this will just create a 4 leaf system in between the LR and CR and will also then create a 3 leaf on all the existing walls that are currently just normal dry wall. So I am very hesitant to do this without some advice first.

I could really use your help on this guys, I want to get this place up and running but I need to be pointed in the right direction.

what do you guys think?

G

It happens! Don't kick yourself too hard...

can you be a bit more specific? What are you hearing? Is it just the isolation that is the issue, or are the other problems too? For example, is it that you can hear outside noise / building noise in your LR mics, or is it that the room sounds too dead or too live, or too "something"? Try to describe what it is that is bothering you.

Yup! That will be very important. Try to make them as accurate and detailed as you can.

Which walls? Is that just the outside walls around your studio, or the inside walls too (the ones that you built)?

That's good! At least there's one good thing so far...

Which ceiling? The one in the live room, or the one in the control room? What are the ceilings made of?

Wow! If you start tearing things down, then it would be a good idea to consider trying to use some or all of that extra space in your rooms. Height is a good thing, acoustically.

Sound going "in" and "out" is pretty much the same: If your wall isolates to (for example) 55 dB, then it does that both ways more or less the same.

so how quiet is it right now? If you take your sound level meter in there, and set it to "A" weighting, fast response, what numbers are you getting? What frequencies are giving you problems? Maybe you could make a recording of what that room sounds like: set up a mic that has really flat response, and just record a minute or two of "silence" in that room, then post the result here. Then without moving the mic or anything else, record another minute or so while you are playing loud, full-spectrum, pink noise in the control room, and post that recording too.

Isolation from what? Isolation from the outside world, or isolation from the control room?

From your rough diagram, it looks like it, but I'll wait for the detailed SketchUp model before confirming.

However, if you have a 3-leaf problem then that will show up in the low frequencies (which is why I asked you to play loud full-spectrum pink noise in the CR while you record what that sounds like inside the LR. 3-leaf issues mean very poor isolation at the resonant frequencies of the 3-leaf system, which will always be in the lows. The exact frequencies are determined by the total mass on the leaves and the sizes of the air gaps between them, so that information is important.

So the question is, do you have a low-frequency isolation issue, or a general isolation issue across the entire spectrum? Or maybe just lows and mids?

Yep, that probably would make matters worse! Not only that, but you'll lose a lot of floor space and room volume, which will make the room worse, acoustically. I'd try to fix whatever is wrong with the existing construction, instead of building something new.

The first thing I see from your diagram is that you don't seem to have decoupled anything form anything! There are flanking paths all over the place, and all the leaves are tied together in different places, so I'd suspect that you aren't getting more than maybe 30-something dB of isolation from that, 40-something, tops. If that's the case, then the problem will be across the entire spectrum, not just in the low end: you'd probably even be able to hear speech through the walls.

It can all be fixed, probably, but we'll need more details first, to figure out what exactly is wrong and how to go about fixing it.

- Stuart -

_________________
I want this studio to amaze people. "That'll do" doesn't amaze people.

Hey Stuart,

Thanks for the reply and the help. Really Appreciate it. To answer your questions...

The problem with the live room is more a building noise issue. If the mic gain is high enough i can hear strange (probably flanked noises) not sure how to describe them and im pretty sure they are coming from the elevators and buildings main hvac plants these noises are quite distant and infrequent but still annoying. But as you say I have flanking going on everywhere. Periodicly there is some noise from a truck or something driving by outside. The second issue I have is the noise from the live room monitors but I guess this is a given from the fact that my walls are just coupled dry walling.

I don't have a sound meter unfortunately so cant give you exact figures at this point. I am definitely going to do some recordings of the room and using the pink noise approach you mentioned but will probably only be able to do this over the weekend.

Currently the ceiling runs right through the entire wing but the live room does have a second ceiling underneath the main ceiling (obviously not helping much).

Unfortunately I cant use the cavity above the ceiling for extra space as it is full of duct work for the buildings main hvac and ceiling support systems. Note that I'm not getting noise from that duct work as it is all sealed off above the studio and currently isn't coming into the studio.

I definitely cant hear speech through the walls to the outside and not through the wall in between the LR and CR either. Even though the studio walls aren't decoupled they are all airtight and insulated top to bottom (doors too) so im guessing this is why there is some form of transmission loss going on compared to a standard hollow unsealed drywall.

I have made a sketchup model for you to examine. Its accurate within millimeters and is fairly detailed. To make it as easy as possible for you I have grouped and made as much components as possible.

Dry wall boards are grouped together, Insulation inside the the walls - grouped, entire ceiling structure is a group, tracks and studs as well. So you can hide and un hide the separate groups all over to get a good breakdown of the construction. The concrete slab above the ceiling (colored red) is in the model as well and I have drawn in the floor plan for the surrounding area on the studio level.

You will notice the flush mounted monitor housings in the front wall are also included and I've shown how we surrounded them with insulation and mounted them on double brick pillars. The model does not include the second ceiling in the live room, but it is just a flush plastered ceiling sitting about 50mm below the one that is in the model also supported by the slab above with supports going through the ceiling above it. In reality both ceilings are present they are supported by wire that is fissure plugged into the concrete above. The entire ceiling is also covered top side with the same insulation that is inside the walls. The model is saved with the ceiling and top slab hidden.

I thought of a way to reconstruct the live room walls today and thought Id run it by you. I will post the idea after this, by looking at the model you will be able to understand what I am on about.

Thanks again for the help!

I cant upload the model as the file size is 4.6mb. How else can I get it to you?

G

My idea for the decoupling the live room walls:

Firstly, completely remove the ceilings and ceiling grid inside the live room, so that the ceiling grid that covers the entire wing (and control room) stops at the outside leaf of the wall right around the live room.

Then, remove all the boards from the walls inside the live room.

Completely remove the straight wall in between the live room and control room, exposing the inside of the angled wall of the control room and back of the flush mounted monitor housings.

Leave a 50mm gap and put up new wall framework right around the inside of the live room, completely free standing of the existing (now inside = open) walls.

Insulation inside the new frame.

Board up the new frame effectively creating a 2 leaf wall where the inside and outside leaves are completely decoupled by a 50mm gap.

Add extra boards (green glue?) to the new inside leaf.

drop a new ceiling onto the inside leaf wall of the live room.

Add a second door to the inside leaf.

I estimate a loss of floor space of about 150mm off of each wall right around the inside of the live room. I can live with this, the room will still be comfortable for a drum kit or vocalist. Will this idea work or am I still on the wrong track?

G

Ok so since I don't have a propper spl meter the next best thing I could do right now was put the pro audio tools app on my iPhone to use. I generated a pink noise in the control room and the app told me it was 105db (A weighted). Then went into the live room and the app gave me 54db. So that's a 51 STC if I understand it correctly?

This is according to an iPhone app tho so I'm guessing the actual number is probably a bit lower. As I said before I will make some recordings over the weekend and post them up.

G

I wouldn't rely on that being very accurate! I somehow doubt that the 99 cent microphone in an iPhone, and a 2 dollar pre-amp and digitizing circuit, and a 5 dollar app, are going to give accurate acoustic information! But it works to get a very rough idea.

I actually tested that in practice when I was doing acoustic tests in a church a couple of months back: As I was taking the readings with my spectrum analyzer, the pastor pulled out his iPhone to compare what his "spectrum analyzer" app said: Huge differences. As much as 15 dB in some bands. He was shocked by how inaccurate his "acoustic analyzer iPhone" was.

But at least you are getting a very rough ball-park figure for comparison with yours.

That is showing an overall transmission loss (TL) of 51 dB for the frequencies that the iPhone cna handle, not an STC rating of 51. STC is a rating system where you have to take several readings in several different bands, then fiddle and fudge them around, figuring "deficiencies" and "adjustments", until you can get your curve to fall right under an STC reference curve. Then you claim that the value of the reference curve is the STC rating of your wall. Its a kludge at best and only deals with a set of frequencies in the mid range: it does not consider low frequencies at all, and is a lousy system for measuring studio isolation.

But if you are getting 51 dB TL, then that's reasonable.

And a bit inaccurate! I'm not sure of the frequency response curve of the iPhone mic and audio circuits, so you might actually be measuring anything, but I very much doubt that there is anything usable in the bottom couple of octaves, which are the most important for studio isolation. So even if the reading of 51 dB TL is accurate for the frequency bands that the iPhone covers, my guess is that it is not covering the ones that you need it to cover, and the actual TL is going to be substantially lower. I may be wrong, and the iPhone actually might have a wonderful mic and circuit, with totally flat response from 20 Hz to 20 Khz, but that seems a bit unlikely!

I'd try to repeat those measurements with a proper, calibrated sound level meter.


OK, comments on your previous post:

Sounds like some of it is impact noise and structure-borne noise that you are hearing. Properly decoupling the inner leaf from the outer leaf will help with that, but your floor might still be an issue.

Could be the same thing: vibration getting into the building structure itself from the road surface, then appearing in your walls. Once again, floor might be an issue.

Yup! But there are ways of fixing that.

You can pick up a good one on eBay for under a hundred dollars, but not sure how useful that would be. Also, I'm not sure if they are still around, but there used to be a store in downtown Jo'burg, just a few blocks up from the Carlton Center, called "Hamrad". They would probably carry sound level meters, or at least tell you where you can find one. Don't recall what street it was in, but about 2 or three blocks up, on a street running east-west. There was another electronic components store on the same street, a few blocks west. But that's probably all changed now! I'm talking about 30 years ago!

OK, so there's a big issue, right there! That implies that you have a 3-leaf ceiling in the live room, with the center leaf being fully coupled to the CR ceiling, which is 2-leaf... That might explain why you don't have good low frequency isolation from building sounds, too. That 3-leaf thing might be showing it's ugly head.

OK, so speech is isolated, but lower frequencies are not. I'm still thinking "3-leaf" and "decoupling"....

Is there any place you can upload that file, so I can download it?

Assuming that both of those "ceilings" are the equivalent of 12mm drywall, then the resonant frequency of that ceiling is about 90 Hz! Meaning that the ceiling does not isolate below125 hz, starts isolating reasonably at 178 Hz, and isolates well above 268 Hz. That's for 2-leaf. If it is 3-leaf, then things are even worse. Those figures become 118, 166, 236 and 354 for F-, and 167, 234, 334, and 500 for F+. That would explain a lot!

Yes!

Yes, but the gap needs to be at least 100mm, and preferably 150mm. However, I'm talking about the gap between the LEAVES. not between the FRAMES. In other words, the gap between the drywall surface that face each other across the cavity, regardless of the stud framing. That's what matters. Get that gap as big as you can, but never less than 100mm.

Yes, but the RIGHT type of insulation. Not sure what you are using now, but the density needs to be correct: about 30 kg/m3 if you use fiberglass insulation, and 50 kg/m3 if you use mineral wool insulation. Completely fill the cavity (but without forcing it in: just laid in gently) if your local building code allows that. If not, then fill as much as the building code allows.

Exactly. The drywall should be 16mm, not less.

Yes. can you get Green Glue in the RSA? If so, great. And both layers of drywall should be 16mm, with the joints between the boars offset or "staggered" (so the joints on the second layer do not line up with the joints on teh first layer. GG would be great, if you can get it.

Yes. same rules apply: the ceiling joists for that ceiling can ONLY rest on the new stud walls, and cannot touch anything else.

A very MASSIVE door, with double or triple seals all around the edges. Door seals are a common weak point in studios. Each seal must go around the full perimeter of the doorway (top, bottom, both sides).

Sounds good to me, but it would be better to see the final plan in a SketchUp model.

Also, you might not need to take down as much as you are thinking. Some of it might be OK.

But there's two things you didn't mention that are both common sources of isolation issues: Your HVAC system, and your electrical system. How are those done? From what you said, your HVAC system is totally separate from the building HVAC; and that's good, but how is yours built? Do you have silencers on every wall penetration? In other words, wherever a duct goes through a wall, is there a proper baffled silencer on at least one side of that? Are the ducts line? Are the air speeds and volumes correct? Etc. Ditto for the electrical system: electrical conduit is an easy path for sound to get through. All of your conduit must be sealed at both ends. You can do that by stuffing a bit of insulation into the end of the pipe, then sealing over that with a thick dab of acoustic caulk. If you ever need to pull new wiring through, you can pull of the caulk, pull out the insulation, and the conduit is free again.

That's about all I can think of for now. Photos, test results, and SketchUp models would help a lot to try to understand what is going on.

- Stuart -


- Stuart -

_________________
I want this studio to amaze people. "That'll do" doesn't amaze people.

Stuart your a legend, thanks so much.

I will upload the model to 3D Warehouse in a minute and post the link here for you.

I decided it might be worth while to do the same thing to the control room walls and ceiling as what i proposed for the live room.

I was up all night last night drawing a model of the alterations I propose to do, i will be done with it in about 30 min and upload that too. Then you can have a look and comment on if the solution will work. Its some serious structural re work (especially if I do the CR as well) so I'm not going to move forward with it until I am absolutely certain I will get results.

When I said 50mm gap I meant between the frames, each track is 63.5mm wide so that gives a total "leaf to leaf" cavity of 177mm in most places. If I do the CR as well the cavity will be about 300mm where the glass window sits between the two rooms. Sorry should have been more specific.

The Insulation I intend to use is 47.5 kg/m3 I can also get 24kg/m3 if that will work? Apparently there is only a 0.05 difference in the NRC between the 47.5 and the 24.

I don't think I can get Green Glue in SA unless I import myself (I would do this but I don't have the time to wait for it) What else could I use to glue the boards together?

Unfortunately the most common board thickness you find here is 12.5mm (that's what the place is built with right now) I can get the firewall boards (15mm thick) but they are considerably more expensive. Guess Ill just have to bite the bullet and pay on that one.

I've also been looking into ceiling tiles with high NRC ratings and will probably use these on the new decoupled ceilings.

Hvac is non existent at this point but I have drawn up plans for baffle boxes as well as motorized duct dampers so that the system can be controlled once its in. Fist I need to fix the walls.

I'm not sure how much flanking I could possibly be getting from the floor its pretty thick concrete, at least 500mm and the ground floor is double volume so I'm two stories up from the floor below me and there is nothing on the second floor above me. But just in case, how could I go about decoupling the new inner leaf walls from the floor? I know I would need to use a neoprene or similar rubber and calculate weight tolerances so as to not exceed the rubbers max out point but would you see this as a necessary thing?

Thanks again man. Will post models shortly.

G

Ok, I have uploaded both models to 3D Warehouse.

The first model:

http://sketchup.google.com/3dwarehouse/ ... revstart=0

This is the studio as it stands right now. Detail of the walls, insulation and framework as well as the ceiling and slab above and below. All grouped for easy hiding and un hiding. Note: Saved with ceiling and top slab hidden

The second model:

http://sketchup.google.com/3dwarehouse/ ... revstart=0

This is the alteration I propose in order to decouple the walls and ceilings. Top slab is not in this one. I had drawn the boards at 12.5mm thickness already and hadn't staggered the joins where they stack. Obviously in reality i will use thicker boards and stagger seams. Note Saved with ceiling hidden. Will this work? Any other suggestions?

G

One more thing. I know it would obviously be ideal to decouple both rooms. But would it still be ok If I only did the alterations to the live room and left the control as is? The only thing that bothers me about only decoupling the live room is that the back of the monitors will end up sitting inside the cavity in between the two rooms. So im not sure how well it would work.

G

That looks much better! The LR walls are great like that, and you should get good isolation. I'd need to see the ceiling plan too, but the wall plan is fine.

The front of the CR is also correct now, and those speaker soffits are also good, for the basic idea. Need some fixing up, but the basic concept is OK.

On the side of the CR there is an issue: the window to the outside! There is only ONE piece of glass there. Only an outer leaf, no inner leaf. You should have a second pane of glass, several cm away from the first one. The way you have it now, the glass is the inner leaf, but also the outer leaf, so you are not getting good isolation like that, and that is a major flanking path. That needs to be fixed.

Not the way you are showing it in the new design! In your file "StudioFix2", you have the soffits fully enclosed, which is correct. The speakers are not in the cavity: they are in the soffit. The way you had it before, the speakers really were in the cavity, which is wrong.

So carry on with the design you have now, and start working on the details. For example, a single sheet of drywall on the soffits is not going to be enough. I'd go with very thick MDF, plywood or OSB, all around the soffit. You should also have a heavy duty shelf or stand inside, for the speakers to sit on, decoupled from the front panel. You can use the entire lower section (underneath the speaker shelf) for acoustic hangers. You can adjust the position of the speakers to be about 2/5 the way across the panel, rather than in the middle. Etc. Take a look at John's basic design for soffits, and you'll get the idea. Adapt it to your room shape and your speakers.

In the original design you did, in fact, have a 3-leaf system! the wall between the CR and LR is triple leaf, so the low frequency isolation would not have been very good. Not only that, but two of those leaves were fully coupled by the frame. I'm not surprised that you had some bleed between the rooms!

What TYPE of insulation is it? 47.5 kg/m3 would be perfect, if it is mineral wool, but that's a bit heavy if it is fiberglass. On the other hand, 24 kg/m3 would be perfect, if it is fiberglass, but too light if it is mineral wool.

If they are different materials, then that makes sense. But NRC is only part of the story: you should take a look at how they behave in different frequency bands: two different insulation batts both rated at the same NRC number can have very different performance in low frequencies.

Nothing! Do not glue them together at all! That would be a mistake. Green Glue is not glue: it is a visco-elastic polymer, design specifically to provide constrained layer damping between two layers of drywall or other large massive surfaces. But it is not glue, and cannot be uses as glue. It is acoustic treatment that helps with low frequency isolation, and there are no substitutes, so far. Or at least, none that are fully documented and proven to work as advertised. so if you cannot get GG, then don't use anything at all. Just nail each layer of drywall to the studs in the normal manner, with the second layer offset from the first so that the joints don't line up. And of course, caulk each layer individually, with good quality acoustic caulk.

That's the ones you need: 15mm fire rated drywall should weight about 12 kg/m2, which is the right stuff.

If that is very expensive, then take a look at the prices of 16mm plywood, MDF and OSB. They might be cheaper. Also take a look at 12mm fiber-cement board: It is much more dense than drywall, so you can use thinner sheets. Two sheets of 12mm fiber cement are actually more dense the two sheets of 15mm drywall. Or you could use one layer of 15mm drywall and one layer of 12mm fiber-cement. OR one layer of 16mm plywood and one of drywall. Etc. There are options, so find out which one is cheaper. Sound waves really don't care how much you PAY for the mass! They just care about how much mass there is.

Actually, I think you are missing the concept a bit here: You already have a concrete slab floor above you, with some type of framework hanging on wires, and drywall sealing that up, with HVAC, piping, electrical, etc. stuff inside that cavity. Leave it like that. Seal it up well, and if you want maximum isolation then add an extra layer of 15mm drywall to that ceiling, if you can so so safely (consider the weight), for extra mass. That will give you a two leaf ceiling, but that's no good for what you need: you will have to build a 3-leaf ceiling. unfortunately, but you don't have much choice.

So what you need to do for the final ceiling over each room /the third leaf), is the exact same thing as the walls: framing across the top, two layers of 15mm drywall screwed to that framing, and stacks of insulation in the cavity. That's it! Nothing more nor less. Ceiling tiles will not do what you want, and you'd end up with poor isolation again.

Great! Add those to your SketchUp when you have time, so we can check that there are no issue with that. The silencers can go in the ceiling cavities.

It's a combination of flanking and structure-borne noise. Yes, your floor is thick reinforced concrete, but it isn't damped, and sound travels very, very well through solid, dense things, like concrete and steel. Ever see old western movies, where the hero puts his ear on the railway line, to see if there is a train coming? He can hear the structure-born sound of the train through many MILES of steel track, long before he can hear the noise through the air. Solids transmit sound much better, and much faster than air. So any sound that gets into the building structure will be transmitted to all other parts of the structure, very easily. Things such as elevator noise, water pipe noise, pumps, motors, doors, footfalls, etc. easily travel through building structures, and into your floor, which then vibrates and transmits the sound into the room. If someone bangs on their concrete wall with a steel hammer ten floors above you, or ten floors below you, you'll be able to hear that on the floor in your room.

Floating your walls is not the answer: the problem is in the floor, not the walls. The floor is a drum head (membrane stretched over a cavity), and it will transmit noise just like a speaker cone does.

It's a little more complex than that, but that's the basic idea. The calculations are all about the amount of deflection need in the rubber to not overload it but also not "underload" it: either way will flank. Plus rubber thickness, plus isolating the anchor bolts, etc. But like I said, it's not the walls that are causing the problem: it's the floor. Yes, if the floor is creating a problem, it could also be transmitting that into the walls, so floating your walls might be a possibility, but it isn't as easy as just putting down a rubber strip and sitting the walls on top.

For the floor problem, you might need to float your entire floor, but that's a big job, and expensive. And getting it wrong can make things worse! Here's a thread all about floating floors, so you get an idea of what is involved:

viewtopic.php?f=2&t=8173

And if you want to get into the technicalities of what works, what doesn't, and why, then this is one of the best research papers on floor systems:

http://www.nrc-cnrc.gc.ca/obj/irc/doc/p ... /ir802.pdf

However, it might not be necessary to go that far! Hopefully not. And the good thing is, you can always do it later if you need to. I'd try first with the plan you have so far, adding in the suggestions above, and if you are still not happy after doing all of that, then think about adding a floated platform in your room, using the concept of a drum riser. Basically, just spread a layer if fiberglass insulation over the floor, and put a few layers of very thick plywood on top, screwed together, and not touching the walls, seal the gap around the edges, etc. That's one possibility.

Anyway, hope that helps to get you on the right track!

- Stuart -

_________________
I want this studio to amaze people. "That'll do" doesn't amaze people.

Thanks mate,

Glad were making progress on things now.



I don't know if I can get around this, it might end up being the studios weakest point. Are you talking about the glass where you can see to the outside? And the flanking path you mention being where the splayed wall joins onto it?



When you say the soffit do you mean the walls around the inside corner the speaker is in? Would 32mm MDF work? As far as the front panel of the soffit goes what material should I use? Is drywall board ok or should it be absorbent (fabric?) My understanding of soffits and flush mounting is still a bit hazy. The speakers are currently decoupled from the front panel and will be again in the new design and they will sit on an MDF shelf on top of a brick pillar.



Sorry I wasn't being specific again. Both of the materials I was talking of are fiberglass. Its called energylite around here. Can get it in batts or rolls.



Well at least there are options, the spec I have on the 15mm fireboard is 13kg/m2 so that's right on the mark. I have some 44mm thick chipboard lying around, I pulled it out of an old office space when we refurbed it and kept it as I thought I might be able to use it. It was being used for wall in the first place. Problem is I have no clue what its density is. What do you think? 44mm chipboard + 1 layer of 15mm drywall as a leaf? Or too much of a gamble maybe? I can post up a pic of it if it will help.

I got some prices on green glue around here and its daylight robbery (12 tubes costs more than all the boards and tracks and studs ) so I'm probably going to end up going the other route and screw the layers together, at least the leaves are still decoupled.

I think for ceilings I'm going to leave the CR as a straight forward set up suspended from the slab above. Decoupled from the outer wall leaf, just sealing up on the inner wall leaf.

For the LR I will do the same but add a second ceiling as you said. What if I supported the first leaf of ceiling from the ground up with a load baring framework and then above that i have a second leaf suspended from the slab above?

The wire suspended ceiling systems are rated up to 20kg/m2 so I wouldn't pull off a double 15mm board on that without an engineers guidance (which probably wouldn't be difficult to get) but id rather find a simpler solution, Maybe the fiber cement boards would work better for the ceiling? In the end the ceiling is going to come after the walls so we have some time to work it out. I want to start the work on the walls in two weeks from now so I need to get all the planning finalized now.

Thanks again Stuart your really helping me out here.

G

Hey,

When you've got a chance. I've updated the studio refurb model. The left wall is now decoupled and added a frame with second piece of glass. Also drew in the frame and glass between LR and CR. If you wanna have a look:

http://sketchup.google.com/3dwarehouse/ ... revstart=0

G

See ceiling plan in next post

Hey,

Ok so ive been looking into the ceiling thing and I contacted the technical guys over at the dry wall and ceiling suppliers. They've given me the info on how I should hang the ceiling in order for it to support the weight of two 15mm drywall boards. So basically that is what I will be doing. New grid only to the inside leaf of the room and then putting 2 off 15mm dry wall boards up onto it, with insulation inside, caulk right round and plaster.

I then plan to build a bulk head right around the perimeter of the room about 50mm below the ceiling. The bulk head will house the lights, both recessed LED strips and down lighters. Not only will this look pretty nice but it also solves the problem of the lights creating holes in the actual ceiling. Do you foresee any problems with this?

This illustrates an example of wall and ceiling between CR and the passage outside. Obviously the new wall between LR and CR will be thicker with more boards. Have a look and let me know what you think?

One last thing, in my last revision of the sketchup model youl see I angled the glass between the LR and CR. After some research I have decided not to do this and both glass panels will be mounted straight. This will also create a 250mm gap between the two which should be pretty decent for isolation. The glass I have is 6mm laminated.

Thanks

G

Is there any reason why you don't want to do the ceiling in the normal, conventional, economic, and simple way? Why do you need to go to all that trouble and expense?

- Stuart -

_________________
I want this studio to amaze people. "That'll do" doesn't amaze people.