HUB Studio

[Hub]

Hi everyone.
We are currently designing and building a recording studio in the middle of a building.

The existing structure:

North/East Walls - 200mm Bessa block
Floor - 19mm Particle board + 250 x 60 bearer + 2 x 15mm Fire-check plasterboard + commercial premises under.
Ceiling - Suspended ceiling with basic acoustic panels.
Roof - Metal Clip-lock.


The studio is on the left of a stage area. We have filled in the corner with (2 leaf) walls to the south & east and applied a acoustic panel treatment to finalize the studio footprint.

SW1.jpg

SW2.jpg

The internal studio plan in the 3d is not the current plan and has been greatly revised.

SW3.jpg

This plan was our first new design.

ST 1.jpg

Then moved to this design after some discussion.

ST 2.jpg

Then finally to this plan which we will start to refine.

ST 3.jpg

Would love to know what you all think. It is late now and I will post more details shortlly.

[Hub]

This studio will be used for all sorts of genres.
We have to keep the door which accesses the stage with a small staircase from the studio.

-We need help in working out our ceiling construction. Since there is a suspended acoustic ceiling in place, our thoughts are to create a new ceiling underneath this.
-Guidance on wall construction. The north west studio walls are made of 200mm bessa block and the South east walls are 10mm plasterboard + 90mm timber frame + fiberglass insulation + 10mm plasterboard. The plan shows a separate wall within the studio for both the CR and the vocal booth. We have the option of recording on the main stage in the auditorium as well.

- We need help with the option of a suspended floor. We think we need to go down this track as there is a commercial business underneath. It operates about 3 days a week but we have to assume
that it could be 6 days.

- If you notice in the elevation that the ceiling is sloped upwards towards the CR window. Is this a problem since I notice many studios around the world have either a level or sloping in the reverse direction ceiling.

Would love to hear any comments.

[Hub]

Is it possible I have posted this design in the wrong part of the forum? There seems to be absolutely no activity here. Should this be in the studio design area?

[Soundman2020]

Hi there "Hub". And welcome to the forum!

Is it possible I have posted this design in the wrong part of the forum? There seems to be absolutely no activity here. Should this be in the studio design area?

It's fine. You posted in the right place. The problem is simply too many active threads and too few responders! There are only a handful of of moderators and other members who are answering threads at the moment, and a lot of active threads, with lots of questions. I'm sure someone will get to yours soon! I have yours lined up on a whole bunch of tabs that I have open and awaiting response.

I wish there were more people responding to threads like yours, but tight now there just aren't!

- Stuart -

[Hub]

Thanks for the response Stuart.

Were really exited about this project. Its a DYI project with a bunch of us putting our heads together.
I didnt realize until last night that the 'John Sayers Productions' writing up on the top right of the forum was a button that took you to a wealth of great information.

Really need help with suspended floor design and ceiling design.

Anthony

[Soundman2020]

You sure do pick 'em!

Floor - 19mm Particle board + 250 x 60 bearer + 2 x 15mm Fire-check plasterboard + commercial premises under.

So if I'm understanding correctly, your floor is just a single layer of 19mm MDF? Not even OSB or plywood? MDF is probably not a good choice for a floor.

Question: Is there any chance you could modify the ceiling on the room below?

Roof - Metal Clip-lock.

I'm not familiar with "Clip-lock". Do you have any links to the manufacturer, or photos of what that is?

We have filled in the corner with (2 leaf) walls to the south & east

How is that built? Block? Stud-and-drywall? Brick? Something else?

Also, if that is already a 2-leaf wall, and you plan to build more walls inside it, then you have a problem: you are going to end up with 3-leaf or even 4-leaf walls. Not good for low frequency isolation...

... applied a acoustic panel treatment to finalize the studio footprint.

I'm not sure I understand: acoustic panels do not define the inner leaf of a room. Acoustic panels are treatment, not isolation. They have practically no effect on transmission loss, and cannot be used to create the footprint of a studio. The footprint is defined by the massive, solid, hard, rigid inner-leaf walls. You then add acoustic panels with that inner-leaf, as needed to treat the room acoustically.

This plan was our first new design.

I'm glad you changed that! It would not have been very useful, acoustically.

Then finally to this plan which we will start to refine.

That's an improvement, but there might also be other layouts. The live room area seems rather small, for example. You show space for at least a dozen people in the CR, but barely enough space for two in the LR.

Also, if I understand your drawings correctly, the ceiling is much lower at the back of the control room, and higher at the front: that is backwards form the way it should be. The ceiling should be lowest at the front, over the speakers, and highest at the back, over the couch.

This studio will be used for all sorts of genres.

OK, but how loud are you inside, and how quiet do you need to be outside? Those are the two key questions that determine isolation. You should measure those levels with a sound level meter, set to "C" weighting and slow response.

We have to keep the door which accesses the stage with a small staircase from the studio.

There's only one door there, so you won't get much isolation from that. You need two doors, back to back, one in the inner-leaf, the other in the outer leaf, to get decent isolation. One door alone will not do it.

Since there is a suspended acoustic ceiling in place, our thoughts are to create a new ceiling underneath this.

As long as you remove the suspended ceiling first, then yes, that would be a good option. If you leave that ceiling in place, you will have a 3-leaf ceiling, which is not good for isolation.

and the South east walls are 10mm plasterboard + 90mm timber frame + fiberglass insulation + 10mm plasterboard.

As I suspected, you already have a two-leaf wall, and a very thin one at that. You won't be getting much more than about 25 to 30 dB of isolation from that. You need to modify that wall to make it into a single leaf again, so you can build your inner-leaf next to it. To do that, remove the drywall from the side facing your studio, take out the insulation carefully (you can re-use it), then cut strips of 16mm drywall (plasterboard) to fit between the studs in that wall, hold them in place with cleats, and caulk all around the edges, carefully, with acoustic caulk. Then repeat that with another layer. Then put the insulation back in. That will give you the necessary mass for your outer leaf.

The plan shows a separate wall within the studio for both the CR and the vocal booth.

Exactly. Each of those needs its own individual inner-leaf, built as a stud frame with drywall on only ONE side, and not connected in any way to the existing structure: In other words, the inner leaf of the CR cannot touch anything except the floor, and the inner-leaf of your booth cannot touch anything except the floor.

-We need help in working out our ceiling construction.

With your inner-leaf walls in place, install suitably dimensioned joists across the tops of those walls, and suspend at least two layers of 16mm drywall from that. Once again, the new ceiling cannot touch any part of the outer-leaf: it rests only on the inner leaf walls.

- We need help with the option of a suspended floor.

I think you mean a floating floor, not a suspended floor: two different things.

You might want to read this thread, if you haven't read it already:
http://www.johnlsayers.com/phpBB2/viewt ... f=2&t=8173

If you do decide that you need a floating floor, you'll need to call in a structural engineer to tell you how much extra load you can place on your existing floor structure, and how to beef it up if needed. Floating a floor is a pretty tough undertaking, and the floor will be very heavy, so this is a must: you do need a qualified structural engineer for this.

- If you notice in the elevation that the ceiling is sloped upwards towards the CR window. Is this a problem since I notice many studios around the world have either a level or sloping in the reverse direction ceiling.

I mentioned it above, before I saw your question: yes it is a problem. The control room should only ever get bigger as you go back, not smaller. At the least, it should stay the same. Ceilings and walls with "reverse" angles are going to give you problems with attaining a good reflection free zone around the sweet spot. However, you can solve this problem with the inner-leaf ceiling that you need to build anyway: that can be angled correctly, or it can just be flat, depending on your design philosophy.

I didnt realize until last night that the 'John Sayers Productions' writing up on the top right of the forum was a button that took you to a wealth of great information.

Oh yeah! This place is a gold mine of very useful information about acoustics and studio design! The more you look around, the more you keep on finding new stuff.

Its a DYI project with a bunch of us putting our heads together.

That's the way many projects are here, so you are in good company! I'd suggest that you get two excellent books to help you out here: "Master Handbook of Acoustics" by F. Alton Everest (that's sort of the Bible for acoustics), and "Home Recording Studio: Build it Like the Pros", by Rod Gervais. The first one ("MHoA") is a great text that takes you through the basics of sound and acoustics, touching on all the theory you need to know, but in a clear, easy to follow way. The other is more of practical "how to" guide, the leads you through the actual design and construction process.

So, to summarize: you should start be setting the isolation goals for your studio: The most basic question you need to answer its "How many decibels of transmission loss do I need?": Based on that, the rest just sort of flows together...


- Stuart -

[Hub]

Wow! Thank you Stuart. It was worth waiting for your reply. Lots of questions to answer and think about.



Question 1: So if I'm understanding correctly, your floor is just a single layer of 19mm MDF? Not even OSB or plywood? MDF is probably not a good choice for a floor.

The existing floor is commercial grade 19mm yellow tongue which is a form of partical board, not MDF (medium Density Fibreboard).


Question 2: Is there any chance you could modify the ceiling on the room below?

The room below is a commercial premises and by fire regulations had to have 2 layers of 16mm firecheck plasterboard. We cannot change this. Above that is a 250mm bearer I beleive and then the 19mm yellow tounge in question.


Question 3: I'm not familiar with "Clip-lock". Do you have any links to the manufacturer, or photos of what that is?

The roof or the building ("metal cliplock" is a real term but only what I think it is) is a conventional commercial metal roofing system here in Australia. There is foil underneath this and I think there is maybe fibreglass insulation say 25mm in between. This roof however is about 90cm above the suspended ceiling in our existing CR/Studio space.


Question 4:How is that built? Block? Stud-and-drywall? Brick? Something else?
Also, if that is already a 2-leaf wall, and you plan to build more walls inside it, then you have a problem: you are going to end up with 3-leaf or even 4-leaf walls. Not good for low frequency isolation...

The South east walls have been recently added. These have defined the available space for the new studio/CR. They are made with 90mm studs with one layer of 10mm plasterboard(drywall) and rockwool acoustic insulation and finally on the outer side - 45mm thick battens Polyester insulation and 12mm slotted MDF covered in 1mm fabric acoustic panels (auditorium side). We partly applied the innerleaf with 10mm plasterboard and after reading the forum stopped treating this until we found more information. See pic below.

partially covered wall.JPG

Question 5: I'm not sure I understand: acoustic panels do not define the inner leaf of a room. Acoustic panels are treatment, not isolation. They have practically no effect on transmission loss, and cannot be used to create the footprint of a studio. The footprint is defined by the massive, solid, hard, rigid inner-leaf walls. You then add acoustic panels with that inner-leaf, as needed to treat the room acoustically.

The applied acoustic panel treatment is on the auditorium side which is to finish off the wall and help with the acoustics. This is not designed to reduce sound transmission in the studio.
We will treat the inside of the studio with a suitable acoustic treatment.


Question 6:I'm glad you changed that! It would not have been very useful, acoustically.

Yes we are glad we moved along with our design. Did you notice the panels on the outside of the studio in the 3d picture? these panels are about 120cm x 60cm and finish off the auditorium quite nicely.


Question 7: That's an improvement, but there might also be other layouts. The live room area seems rather small, for example. You show space for at least a dozen people in the CR, but barely enough space for two in the LR.
Also, if I understand your drawings correctly, the ceiling is much lower at the back of the control room, and higher at the front: that is backwards form the way it should be. The ceiling should be lowest at the front, over the speakers, and highest at the back, over the couch.

The latest plan has been revised and the CR wall has been reduced by 300mm which therefore increases the live room by 300mm. I would like to also mention that the auditorium will also be used as a live room and for future posts and I will refer to this as LR A. So the new live room that we are building will be refered to as LR B.
Yes the ceiling is a problem and maybe we construct the angled ceiling and then add extra rafters sloping back towards the CR window. see pic below.

north wall.JPG

Question 8: OK, but how loud are you inside, and how quiet do you need to be outside? Those are the two key questions that determine isolation. You should measure those levels with a sound level meter, set to "C" weighting and slow response.

How loud are we inside? that's a good question. We have a Sound level meter so I will try and get a guitar and amp and dial it up in the studio, take a reading and go outside and then take another reading for reference. We are still trying to determine the level of sound transmission loss we need to acheive. I must say we have residential houses about 15 meters from the north wall and about 50 metres from the west wall. The auditorium regularly has a medium level rock band every weekend. We have had the sound meter out before and have had readings of 90db. We have only rarely got complaints.


Question 9: There's only one door there, so you won't get much isolation from that. You need two doors, back to back, one in the inner-leaf, the other in the outer leaf, to get decent isolation. One door alone will not do it.

The door near the staircase looks like one door but I am actually designing a double door that seals to both walls at the same time ( yes the door will be thick like a bank safe vault. lol). We tried to use seperate doors but we can't have a door that opens over a staircase for safety.


Question 10: As long as you remove the suspended ceiling first, then yes, that would be a good option. If you leave that ceiling in place, you will have a 3-leaf ceiling, which is not good for isolation.

Regarding the existing suspended ceiling. I heard we may be able to glue plasterboard to this and then seal off the room. Then we could build our new timber rafter ceiling under this that would support 2 layers of plasterboard and insulation. What do you think?


Question 11: As I suspected, you already have a two-leaf wall, and a very thin one at that. You won't be getting much more than about 25 to 30 dB of isolation from that. You need to modify that wall to make it into a single leaf again, so you can build your inner-leaf next to it. To do that, remove the drywall from the side facing your studio, take out the insulation carefully (you can re-use it), then cut strips of 16mm drywall (plasterboard) to fit between the studs in that wall, hold them in place with cleats, and caulk all around the edges, carefully, with acoustic caulk. Then repeat that with another layer. Then put the insulation back in. That will give you the necessary mass for your outer leaf.

We are talking about this option now. Sounds like a good idea.


Question 12: Exactly. Each of those needs its own individual inner-leaf, built as a stud frame with drywall on only ONE side, and not connected in any way to the existing structure: In other words, the inner leaf of the CR cannot touch anything except the floor, and the inner-leaf of your booth cannot touch anything except the floor.

Yes this is exactly what we are doing.


Question 13: With your inner-leaf walls in place, install suitably dimensioned joists across the tops of those walls, and suspend at least two layers of 16mm drywall from that. Once again, the new ceiling cannot touch any part of the outer-leaf: it rests only on the inner leaf walls.

Yes this is exactly what we are doing.

Question 14: I think you mean a floating floor, not a suspended floor: two different things.

Yes I mean a floating timber floor. Your diagram in the construction detail section shows a 100 x 50mm Joist. Can we use a 70 x 45 but laid flat so we can reduce the height as we are trying to maximise our height in the CR. Also can we use 6mm high neoprene pads?


Question 15: I mentioned it above, before I saw your question: yes it is a problem. The control room should only ever get bigger as you go back, not smaller. At the least, it should stay the same. Ceilings and walls with "reverse" angles are going to give you problems with attaining a good reflection free zone around the sweet spot. However, you can solve this problem with the inner-leaf ceiling that you need to build anyway: that can be angled correctly, or it can just be flat, depending on your design philosophy.

Yes we have been discussing this and probably will either taper it back towards the CR window or make it flat. This is why we want to keep the floor height as low as possible.


Thanks for your help. I will post some more drawings and details for everyones comment.

[Hub]

Here is an update on the studio plan.

elevation 2.jpg

We are currently looking into a suspended ceiling to seal off the room from the roof and surrounding building. This would mean we will remove the existing suspended ceiling and install this heavy duty
version which can accommodate 2 layers of 16mm plasterboard.

We also changed the shape of the ceiling after discussion and advice from you.

Please let us know what you think

[Hub]

Here are some other photos of the metal beam just above our existing suspended ceiling.

IMG_8821.JPG

The plate thickness of this beam is 20mm! pretty heavy! Yes it has to stay.

IMG_8840.JPG

[Soundman2020]

This roof however is about 90cm above the suspended ceiling in our existing CR/Studio space.

OK; so it will basically be a third leaf, but at a decently large distance that it should not be too much of an issue. That's assuming you plan to do a 2-leaf ceiling.

They are made with 90mm studs with one layer of 10mm plasterboard(drywall) and rockwool acoustic insulation and finally on the outer side - 45mm thick battens Polyester insulation and 12mm slotted MDF covered in 1mm fabric acoustic panels (auditorium side).

That's not good. It sounds like you were in the process of building a thin 3-leaf wall there.

We partly applied the innerleaf with 10mm plasterboard and after reading the forum stopped treating this until we found more information. See pic below.

Yup. Good idea to stop. That would reduce your isolation, as you would have had a 3-leaf wall there. LIke I mentioned in my previous post: I would take that 10mm plasterboard off, and buy some 16mm fire-rated drywall, then use that to beef up the "slotted MDF" from inside the wall, between the studs. Just cut strips wide enough to fit between the studs with a small gap around the edge, seal the edges with acoustic caulk, and hold them in place with cleats. At least one layer, or better two layers, will get you a decent amount of mass.

The latest plan has been revised and the CR wall has been reduced by 300mm which therefore increases the live room by 300mm.

Great! that makes more sense.

Yes the ceiling is a problem and maybe we construct the angled ceiling and then add extra rafters sloping back towards the CR window. see pic below.

Perhaps it would be better to just take the final inner-leaf ceiling straight across, parallel to the floor, the way you show in your final diagram above. That makes sense, and you can use the space above for the HVAC ducting and silencer boxes.

How loud are we inside? that's a good question. We have a Sound level meter so I will try and get a guitar and amp and dial it up in the studio, take a reading and go outside and then take another reading for reference

That would be a very useful measurement! It would tell you how much you are getting right now, which is an important basis for figuring how much extra you need.

The auditorium regularly has a medium level rock band every weekend. We have had the sound meter out before and have had readings of 90db. We have only rarely got complaints.

That's pretty loud! And "rarely" means you have had some already. Most residential areas have noise regulations that you are required to meet. You should check on that with your local municipality: you'll probably find that it is in the region of 55 during the day, and 45 at night. But that is normally "A" weighting, which favors you.

The door near the staircase looks like one door but I am actually designing a double door that seals to both walls at the same time ( yes the door will be thick like a bank safe vault. lol). We tried to use seperate doors but we can't have a door that opens over a staircase for safety.

Take a look in Rod's book on studio design/construction: He has a design for a "superdoor" that does exactly what you want. No need to re-invent the wheel.

Regarding the existing suspended ceiling. I heard we may be able to glue plasterboard to this and then seal off the room. What do you think?

Bad idea! That thin, light framing up there for the drop ceiling is NOT designed to support the huge extra weight of a drywall ceiling. Don't do that: it is not safe, and not a good idea acoustically anyway.

Yes I mean a floating timber floor. Your diagram in the construction detail section shows a 100 x 50mm Joist. Can we use a 70 x 45 but laid flat so we can reduce the height as we are trying to maximise our height in the CR. Also can we use 6mm high neoprene pads?

Did you read that thread I linked you to before, here?:

http://www.johnlsayers.com/phpBB2/viewt ... f=2&t=8173

That explains how to do a floated floor.

We are currently looking into a suspended ceiling to seal off the room from the roof and surrounding building. This would mean we will remove the existing suspended ceiling and install this heavy duty version which can accommodate 2 layers of 16mm plasterboard.

As long as it is specifically designed and rated for that load, with deflection of better than L/360, then you will be fine.

The plate thickness of this beam is 20mm! pretty heavy! Yes it has to stay.

Yup, it sure does! That ain't goin' no place!


- Stuart -

[Hub]

Hi there.

Just a update on the studio design. We have worked out the walls now and are refining construction design.

5s.jpg

1s.jpg

3s.jpg

4s.jpg

10s.jpg

12s.jpg

13s.jpg

14s.jpg

15s.jpg

16s.jpg

17s.jpg

This is the first time I have used sketchup, fantastic free program. Thanks for the recommendation John.


Let us know what you think.

[Soundman2020]

This is the first time I have used sketchup, fantastic free program.

Not bad, for the first time! In fact, pretty darn good!

The only thing I'd suggest is that you switch to perspective view, instead of parallel: Go to the "Camera" pull-down menu, and click on "Perspective". That's much more realistic.

If you post the SketchUp model here, or upload it to Dropbox (or some place like that that allows for large files), then folks here can download it and take a close look at what you are planning.

Nice work with the design, by the way!


- Stuart -

[Hub]

I have tried the perspective view before but with this unusual design with angle everything it distorts too much and gives a false sense of proportion.

[Soundman2020]

I have tried the perspective view before but with this unusual design with angle everything it distorts too much and gives a false sense of proportion.

What field of view angle did you use? If you set it correctly, there is no distortion. On the other hand, parallel projection actually does distort the view, since it does not produce an image that is true to real life: objects are shown out of proportion. Parallel projection is best used for plan and elevation views. This effect is not related to any particular design, no matter how unusual or how angled, but rather to the way the real world works: in the real world, objects further away from the observer appear smaller than objects that are closer. Parallel project shows them at the same size. That is distortion, and leads to confusion in understanding the design and the relative location of objects within the model.

So if you are seeing distortion in a perspective view, then you must have the field of view set incorrectly.


- Stuart -

[Soundman2020]

Another thing I just noticed: I hadn't picked up on it before, due to the distorted viewpoint of parallel projection, but it seems like you are planning to float your CR floor? That's not good. A raised or floated floor done the way you show it will lead to major resonant issues. The floor will act either as a drum head, or as some form of resonant trap, depending on the details. You don't want either of this for a studio floor, and especially not under a drum kit!


- Stuart -