Questions before starting...

After a lot of reading and old-topic-searching, i decided to start a new topic with all the question before go any further. This are the plans of the studio i´m planning to build. The studio is in the terrace of my new house. So it´s really a concern trying to stop low frecuencies to go down trought the floor... The ceiling is sloped on both rooms(3,4mts to 2,4mts - wood and roofing) The outer wall is a brick wall rendered only rendered on the outer side. The inside walls are simple metal frame filled with 50kg/m3 rockwool and 2 layers of 5/8 gypsum on the same side. Here´s a couple of questions... Floated floor: I´m planning to float the floor as the model on SAE site, with Mason Super W pads (50 duro), 2x5" pine studs and plywood (or MDF) on top. Should i try to float my floor at all? I read that sometimes floating a floor can make things even WORSE! Window: I´m using a two glasses window (8mm and 4mm thick) 1,1x0,7mts. Should i use just 4 Mason SuperW pads to "bed" each glass? Any other material to replace the closed cell foam? Control Room Acoustics: I can´t put corner bass traps behind my back, because the entrance door and the RR door are too close to the back wall (is that clear?)... If i put branboard absorbers on the back wall and in the joints of the back wall and the ceiling, am i solving this problem (a little at least)? One of the places where i know i should put some absortion is where the window is... (see the pic), so i have only absortion on the right side of the room... Is that too bad for room acoustics?

Construction started 2 days ago!

Should i try to float my floor at all? I read that sometimes floating a floor can make things even WORSE!

From my understanding, if the Low frequency Transmission Loss in the floor doesn't equal your walls and ceiling, what is the point. But don't take my word on that. Steve is better equipped to answer for sure. Actually, I'm just asking the same question myself. fitz

Yes, that is the question of the ages here. I think there are at least six projects (mine being one of them) where the "to float or not to float" question is holding up progress! I too have become further enlightened by testimony from experts here (and on other forums) that says, essentially, "floating a heavy floor is ideal, but it's a waste of money, time, and effort if your walls cannot 'keep up' with the floor. On the other hand, floating a lightweight floor (and you'd be surprised what is considered 'lightweight') is not only 'not ideal,' it could be worse than if you do not float a floor at all." Obviously (as you have already discovered), floating a heavy concrete floor on a surface other than the ground level can be a deathly disaster. :!: You're kind of "between a rock and a hard place" as we say here (i.e., no ideal solution), given your need for a lot of isolation and the fact that you're on the second floor above your sister's bedroom. By the way, cool pictures -- I always love seeing project pictures, especially from around the world. However, don't get ahead of yourself -- you should determine exactly what you are going to do before demolishing anything else.

Everytime someone new enters the floater deal, it seems like a new alternative is coming. And then they get sucked into our favorite little delima. Welcome, and hang on, Its a bumpy ride

Hola Julian, veo que ya comenzaste tus obras. Suerte!! :wink:

Just in case folks have forgotten what the "before" photo looks like...

Thanks guys! I found this forum really encouraging. Anyway... The first step is the demolition part and raising the walls that need to be made. After that, i´ll buy the materials to start building the inner walls and stuff. So, i have time to changes a couple of things if needed. I know that my situation is not ideal (i wish it was!), but i wanna make the best of it. The idea i came up with was to float just the place where the drums will be and see what happens... If it sucks, i can still use it to raise and amp or whatever, and if works, i can float the entire floor. The floor will be reinforced with cement... (see the pic). I know it´s not enough, but al least it´s a little more mass. I found REALLY exciting the hole progress of making an homestudio, and i really KNOW that hurry the hole thing up is a bad idea. So, i won´t do it. Gracias Hugo! Espero que tu estudio sea un éxito! ;) I really appreciate all the time that you guys "donate" trying to help people all around the world to make the best possible studio that we can make. God bless you! :) Oh, btw, if anyone have the time to answer question by question it would be great! (yes, even greater!)

Hey guys, please don´t forget about me! ;) Just kidding, i really respect your time... but i just can´t help myself! :oops:

Here is a field test that might be as close as you could get considering weight limitations; note the stated weight per sq. foot of 32 pounds - Can you re-post your floor specs, specifically framing size/type/material/spacing, span, etc? I'm thinking at this time (you too, Keith) that the best approach here is to build WITHOUT floating a floor FIRST: but do it in such a way that an "inside the walls" floated floor could be added later if necessary. Julian, in your case the weight will be VERY important. I would NOT under ANY circumstances build a "floated room", but instead first build your walls (resting these on the bridge pads is OK, but do it so you can hermetically seal around them with caulk. Then, once the room is up, do some tests between the studio and your sister's bedroom; let her hear these so she can appreciate any IMPROVEMENT that happens due to any floating options you may be able to do. The link at the top of the page would add 32 psf (156 kG/sq. M) to your floor weight, so you absolutely MUST involve a qualified engineer here (IIRC, you've done this but I forget the results, sorry) By only floating the FLOOR, you will minimise the loading on your structure; keep in mind that under ideal conditions this isn't a FANTASTIC improvement, check out some of the other results here - http://kineticsnoise.com/arch/tests/floors.html pay particular attention to the lowest frequencies mentioned, although they will not show what happens at even lower ones; this is where m-a-m resonance comes in, and you're pretty much out of luck on that one; meaning, you can't possibly get m-a-m resonance low enough to be inconsequential with your existing construction, and have your sister live through it. Window - do you have a sketch showing inner and outer leaf of wall, and how they connect with the window framing - specifically, will these panes be in separate, decoupled frames, and what air gap between them? Control room acoustics - I'm assuming the "cloud" area will be where the mix desk is - so yes, for mixing the window will be a problem. That and the rear of the CR (bottom of pic) will require some movable absorbers, so you can see the talent during recording but absorb the window and rear of room during mix. HTH... Steve

Steve... i agree with you. I think the best idea is to to build without floating a floor at first... then make a test and see how many transmision i´m getting on my sister´s room. I think John use this approach (resting inner walls on neoprene) on Snapper's Studio... (see the pic) Is that what are talking about? What do you think about making a drum riser (with neoprene pads and rockwool), to avoid the lowest freqs to pass my floor that easily, and since that area is much smaller than the hole studio, i´m saving a lot of weight and still achieving a better low freq insolation. Is that a good idea? (see the basic layout)

Window - do you have a sketch showing inner and outer leaf of wall, and how they connect with the window framing - specifically, will these panes be in separate, decoupled frames, and what air gap between them?

Yes, they in totally independent frames... The air gap between them is 20 cm. The control room pane beds on a frame that´s hauled in to the brick wall. The live room has his own decoupled metal frame, where the pane rests. (see pics) (btw, thickness showed relates to glass thickness, not walls) You´re right about the cloud and mixing desk position... I´ll make a couple of mobile absorbers... ;)

I think John use this approach (resting inner walls on neoprene) on Snapper's Studio... (see the pic) Is that what are talking about? Yes, exactly. What do you think about making a drum riser Probably the easiest way to get some improvement; if it helps quite a bit, you'll know whether to do the entire floor. Also, it will tell you better than anything just EXACTLY what resonance will do to/for you. The glass itself with those dimensions would be about STC 49, with the TL at 50-60 hZ coming in at around 30 dB. This would be BEST case, and relies on complete seals, no hard contact between frames... Steve

As usual, you´re great, Steve! Qs. What should i keep on mind when doing the drum raiser to get the best possible results... (Should i make some calculations or is just 2x5 studs and 30mm mdf on top -with neoprene and rockwool-) I thought the window would achieve a little better performance... Should i try to make the air gap 30mm wide? (Is that the weakest link, right?)

Any idea? Thanks!

Everytime I start to think I'm starting to get a handle on things I learn something new which seems to totally change things.

sharward wrote:

Yes, that is the question of the ages here. I think there are at least six projects (mine being one of them) where the "to float or not to float" question is holding up progress! I too have become further enlightened by testimony from experts here (and on other forums) that says, essentially, "floating a heavy floor is ideal, but it's a waste of money, time, and effort if your walls cannot 'keep up' with the floor. On the other hand, floating a lightweight floor (and you'd be surprised what is considered 'lightweight') is not only 'not ideal,' it could be worse than if you do not float a floor at all."

What would be considered a 'lightweight' floor in this case? Whats the best thread here concerning this? Thanks, Seth

Steve, i read that you found a way to make a lot of money, and maybe you´ll have less time to share with us... I´m really happy for you, i think that everyone gets what deserves... I´ll try to make my questions more specific... Take a look at the window design... I´m planing to put some insulation between the pads and the Closed Cell Foam between the glass and the cleats... can i use just 6 pads of neoprene (duro 50) for a 1x0,9mts (8mm thick) window? How it looks? How can i replace Celotex (i can´t find it here)? The CCF that you talk about is the same as the one in the picture? I think it´s pretty soft... Can i wrap insulation in corner bass traps with garbage bags, and still have all the bass absorption that i need? (for my control room) I think you said it only affect HF absortion... am i right? I´m planning to use 2 layers of 18mm OSB for my drum raiser... How much should i raise it from the floor? Do i have to make any calculation to prevent undesirable resonance? Thanks man!!!

Pretty close, Julian - here are a couple of dwg's I did some time back, easier to re-post than try and find them - If you can't find Celotex, look for Homosote - if no luck there, since there isn't a wide un-supported area you could use 1" thick rockwool covered with dark colored cloth - it's mainly there for looks, but needs to breathe... Steve BTW, I doubt I'll be "going away", but it may take a little longer for answers during any "rush" video projects - how could I leave such a great group of friends???!? :mrgreen: :mrgreen: :mrgreen:

Hey steve, how about this? can i use just 6 pads of neoprene (duro 50) for a 1x0,9mts (8mm thick) window? I can´t "read" how many pads use from your (great) layout.. The CCF that you talk about is the same as the one in the picture? I think it´s pretty soft... Can i wrap insulation in corner bass traps with garbage bags, and still have all the bass absorption that i need? (for my control room) I think you said it only affect HF absortion... am i right? I´m planning to use 2 layers of 18mm OSB for my drum raiser... How much should i raise it from the floor? Do i have to make any calculation to prevent undesirable resonance?

Steve? Rod? Anyone? :?: Thanks guys!

can i use just 6 pads of neoprene (duro 50) for a 1x0,9mts (8mm thick) window? What I intended for the sketch was a continuous strip, but all you really need is enough NOT to have it deform and mess up the seal; so depending on the size of the pads you have, they should probably support that much glass just fine - that pane of glass should only weigh about 22 kG. The CCF that you talk about is the same as the one in the picture? I think it´s pretty soft... Soft is good; you want complete conformance to any irregularities for a good air seal. If you can find a source locally for the kind of weatherstripping used in automobile trunks and doors that would be best. The type shown in your pic is often OPEN celled, which is NOT what you want. Can i wrap insulation in corner bass traps with garbage bags, and still have all the bass absorption that i need? Absolutely, no problem. as thin as garbage bags are, only the top octave or two would be affected. I´m planning to use 2 layers of 18mm OSB for my drum raiser... How much should i raise it from the floor? Do i have to make any calculation to prevent undesirable resonance? Just damp the living crap out of it; if you have something like asphalt-based roll roofing in your area, I would put a couple layers of that between your two layers of OSB, and a snug fill of insulation UNDER the riser. The deeper your air space, the lower the resonance of the unit but regardless, DAMPING will be necessary. That's what the roll roofing will do, and also the insulation. You don't need ANOTHER "drum head" ringing, especially when it's as big as a drum riser... Steve