John Sayers' Recording Studio Design Forum Archive

A nice hello to all forum members.

Well, iam trying to build my new homestudio. I have nearly finished all 'unimportant' rooms such as the bar, lounge, plant room... but now iam working in the recording and control room.

This forum is a very good source of information, i love it. But i have some questions of course:

Question one:
I will do a floating floor over concrete. I can't find a source in germany for neoprene or EPDM where i can buy these peaces in small quantities (300 or so) at the moment.. But I can get rubber pads with 13mm thickness.
The rubber is from a company who uses these as tie-down for trucks. It is kind of hard. I tried to put a speaker on it and the impact sound reduces much, not completely but much. And to my surprise timber/wood is a good isolator, too. It seems to me that the rubber has nearly the same acoustic isolation than the wood timber. Is that correct? Or do I have the wrong kind of rubber? I don't know anything about the rubber material, nor if it has a shore of 60 or so
Can I use this rubber material?

Question two:
I'd done some framework in the control room. I mounted the framework directly to the floor with nail plugs. I don't know if this was a big mistake after I'd seen some pictures in this forum where the walls are isolated by rubber and the screws which fix the wall to the floor also have rubber.
Is isolating the walls a huge improvement or not? Somehow the walls are fixed to the floor anyway... ?

Question three:
How do i caulk the floating floor at the edges? (the connection from the wood floor to the drywall.
Some picture of the floating floor are showing the fiberglass direclty at the underside of the wood floor... Can the fiberglass lie down on the concrete floor or do i have to prevent the connection of the fiberglass to the conrete floor? http://www.nrgrecording.de/assets/images/IMG_0321.jpg

If you're still reading this - i would like to thank you and i would like to say that i appreciate every help.

I attached some links and drawings of my studio. Maybe someone could give some tips before my work/mistake is irreversible.

Thank you very much,
Frank.



bigger picture here:
http://www.nrgrecording.de/tempfolder/controlroom1.jpg




bigger picture here:
http://www.nrgrecording.de/tempfolder/c ... eview1.jpg



bigger picture here:
http://www.nrgrecording.de/tempfolder/r ... ontrol.jpg


PICTURES of what i'd done until now:
http://www.nrgrecording.de/html/studiobuild.html

hmm.... okay...

somehow i feel that it don't make sense to build a floating floor with 1/2" rubber and 2 layers 3/4" plywood/osd.

I don't know anything about how to calculate the resonance frequency of this floor. I thought it would be just right because i'd seen this kind of floating floor in this and other forums. I only read that Mr. Vermeier and Mr. Desart calculated that the resonance frequency must be around 4 octaves lower than the frequency we would like to stop (20-30Hz?). So around 3Hz.

Iam trying to make a room in room construction, although i dont' know if iam doing it well. In the control room i don't need a good isolation to the outside, only to the recording room. So I thought it would be a good idea not to connect both rooms. I have a concrete floor made of one peace. So a floating floor would do this, i thougt.

At the moment one door frame is made for non floating floor, and one is made for a floating floor. Only the iron girder's base would bug us because its over the concrete floor if I decide not to do a floating floor
http://www.nrgrecording.de/assets/images/IMG_0312.jpg

Now its the point of no return.
I have to make a decision about floating the floor or not. Who can help? A "yes" or a "no" would be enough

I feel your pain. I struggled with the question of whether or not to float a floor for a long time myself.

Here are some of my favorite threads about "the dreaded floating floor decision":

• Float floor on expanded polyester?
  This one has contributions from Rod Gervais, a construction engineer who unfortunately is so busy on multi-million dollar construction projects that his availability here has been quite limited lately, and Paul Woodlock whose amazing project in Peterborough, UK is a sight to behold and not for the faint at heart or the short on time!
  
  Mason Industries' FSN Floating Floor Concrete Slab Test Data
  More great stuff from Rod -- and notice how the "where is everyone who did not float a floor and then later regretted not doing so" question remains unanswered to this day!
  
  Community Studio Build - Help Needed
  This one's about the idea of floating a floor on an upstairs space... But some good points are made about floating a lighter weight floor and the fact that the results could be worse than not floating anything.
  
  Knightfly! Floating floor questions
  One of the most informative all-in-one floating floor threads on the site, with lots of insight from Sir Paul.

You'll probably notice that there's more than a little skepticism in all of the above threads. There are also many threads about presumably successful floating floor and/or floating room projects out there, here and on StudioTips (and elsewhere).

I realize you are in a hurry to get moving... But please don't rush this most critical aspect of your plan. Rushing a floating floor decision and/or design is a virtual guarantee of its failure.

--Keith

Before you get any further, WHY do you feel you need a floating floor? This is a question far too few people ask themselves before starting on construction - the very FIRST question (before even budget ones) needs to be, "How much noise am I, and my neighbors/family, going to make, and how much do I/they care ?"

There is no solution without first a measurement, even if it's subjective - from that, we can figure out just how much isolation is needed, and at what frequencies. Finally, we can then pick from available, LOCAL, options that will accomplish AT LEAST that much isolation.

Doing a LITTLE more than necessary to fix the above is SMART; doing a LOT more is wasting of money that could be utilized elsewhere... Steve

nrgrecording wrote:
Question one:
I will do a floating floor over concrete. I can't find a source in germany for neoprene or EPDM where i can buy these peaces in small quantities (300 or so) at the moment.. But I can get rubber pads with 13mm thickness.
The rubber is from a company who uses these as tie-down for trucks. It is kind of hard. I tried to put a speaker on it and the impact sound reduces much, not completely but much. And to my surprise timber/wood is a good isolator, too. It seems to me that the rubber has nearly the same acoustic isolation than the wood timber. Is that correct? Or do I have the wrong kind of rubber? I don't know anything about the rubber material, nor if it has a shore of 60 or so
Can I use this rubber material?

Just a quick comment on the material question (not taking into account that you still have to decide if you float or not).

I'm basically facing the same question at the moment and I'm located in Switzerland. You may want to consider using Sylomer for the isolators. The manufacturer (Getzner) is in Austria but has offices in Germany as well, so it should not be a problem to get it.

Furthermore, the swiss distributor of Sylomer actually offered me to do the calculation for me - I'll just have to provide them a plan of how the weight is distributed on the floor. I can imagine that Getzner in Germany does that as well, that's basically their core business. Maybe just check them out (www.sylomer.de) and ask. And search this forum for Sylomer.

cheers
Stef

You should REALLY consider Knightfly's post. You seem to have left out the most important information that is needed to tell you whether you even NEED a floating floor or not.

What kind of music are you recording?
Are accoustic drums involved?
What hours are you going to operate?
How close, and where are your neighbors?
Is anyone above or below you? Do you share any common walls?

In my case, I have a stand alone building with filled concrete block walls with my nearest neighbor at least 30' away from the nearest wall. At night I can barely measure sound escaping from the building (102 dB+ Led Zeplin inside) and that was BEFORE I started any wall construction.

Are you in a similar situation? As I understand it, the ONLY reason for a floating floor system is isolation - either room to room or room to outside. If this is NOT an issue, then don't waste the money floating the floor. If your only concern is drums, perhaps you could build a floating riser just for the drums.

Putting some sort of rubber/foam product on the floor and laying a wood framing does NOT make a floating floor. You have to use the RIGHT rubber, in the RIGHT size and RIGHT shape and include the weight of your walls, ceiling, equipment, bodies in the room, etc. in your calculations.

If the rubber type/amount/placement you have is to soft, the whole structure will "bottom out" (squish the rubber all the way to the floor) and you might as well bolt the whole thing down. If it's too hard, you essentially ARE bolted down because the sound will travel through the floated floor, into the rubber, and down through the floor underneath, again a waste of time and money and as Sharward mentioned, it could end up being WORSE than if you'd done nothing.

Too many people here and elsewhere on the net think there is some magical property to putting something soft on the floor and building a studio on top of it. The real magic is in the calculations. How many people have a floated vs non-floated floor IN THE SAME room to compare with? We don't know if it's better or worse than just building on the floor unless there are calculations to back it up. Who is going to build their rooms, test it, then tear out the whole thing, put in a floating floor/room and say, "Yeah, that's better?" If someone was really willing to go to that expense, please send them over to my place and he/she can spend their money HERE to satisfy their curiousity.

I'm not trying to discourage you, just tell you that throwing any ol' rubber like substance on the floor isn't necessarily going to get you any thing. Math is your friend! Do the calculations and then you'll know.

len

Indeed -- all of the points you (Len) made are interwoven throughout the threads linked in my post above.

knightfly:"WHY do you feel you need a floating floor?"

In the beginning the idea for making a floating floor was because i wanted a better sound isolation from the recording room to the control room and from both rooms to the outside.
I'd seen the floating floor idea at the SAE webpages and also in this forum. So i thought... this must be a good idea. So I tried to get any rubber, some rockwool and plywood and tried to start.

But... Last night after reading all the discussion about a floating floor (many thanks for the links!!!) till today at 5 o'clock in the morning (man, this is really interesting) it seems that what iam doing is wrong.

If I understand correctly I have to calculate the resonance frequency, which i can't because i don't know the rubbers values. So in the worst case the floor will not attenuate anything but boost anything in a specific section of the frequency range. (I'd seen the EAR webpage with the diagram) I don't want that

If I understand correctly a proper floating floor will give me a 20% better transmission loss.
Also calculating the MSM isn't easy because the existing floor varied from 15 to 20 cm thickness.


I don't know how much I'd read: "Do it right or don't"
So I think I will... ahem... "don't..."

The only problem then would be to hide the fat metal plate which is now in the control room and corridor. With the floating floor idea from the beginning the metal plate would be "in" the floor. The complete truss and the 1st floor sits on the two iron girder.


---------------------------------------------------------------------------------------

len-morgan: What kind of music are you recording?
Rock. Which means the tama starclassic drums, mesa boogie 4x12 for guitar, ampeg bass amp (the fridge)... so it will be loud. If it would be possible I'd like to do the band-practice in the recording room as well. And band practice time is mostly from 20 to 23 o'clock.

len-morgan: Are accoustic drums involved?

Yes. I think the snare will be the problem and the bass amp of course.

len-morgan: What hours are you going to operate?

Because iam doing this as a hobby I will use these rooms after work and at the weekend. And of course it would be good if I can record anything at the late evening/night.
If I wold know KNOW that I can't record drums at night I can NOW think about making a small booth with better sound insulation in one corner of the recording room. It would be pretty bad to do this when the floor and everything is done.

len-morgan: How close, and where are your neighbors?

I did a picture
The next neighboring house it 3,20m away. But between the recording room and the neighour there is a garage with lime malm brick and clincer. We build the garage last year.

http://www.nrgrecording.de/tempfolder/house2.jpg <bigger picture


len-morgan: Is anyone above or below you? Do you share any common walls?

There is no one above me... the recording room is one room from the floor to the roof. The control room has a 1st floor. On top of the control room there is the plant room and a bedroom or rest room or whatever it will be in the future... but thats only for the studio itselfs... no one is living here of course. The recording room is sharing one wall with the garage behind the recording room, and the garage is sharing one wall with the house. The bedrooms of the 3 tenements are far away from the studio.

len-morgan: Are you in a similar situation?
30'? The nearest neighbor is 3,2m/126' ?? away from the recording room and thats the distance from the garage to the neigbors wall... the garage is betwenn the neighbor and my recording room.

So i bet IAM in the same situation.

But the inner walls don't rest on neoprene or something like this, the drywalls are fixed directly with a lath construction to the roof but with 16cm fiberglass (6inch) and a layer of plastic as moisture barrier. The drywall at all 3 sides are standing directly on the existing floor only isolated with a kind of foam which is always used here in germany for this purpose. Ok, i bet its made for a building industry standard but not for recording studios.
Some time before I placed a 1.2KW PA system in the middle of the recording room and turned the volume up to 10... that was before I did anything in the studio... and it was loud outside. I could hear/feel the impact sound at the outside and my neighbor was looking out of his window.
When I do this test again next time after installing all the walls, adding additional doors... It could be TOO LATE to do anything. So thats my fear.

Regarding the floating floor i did in one room... Isn't it possible to find out the resonance frequency without calculations? I don't know anything about the rubber material and will never find out anything about it.
So one crazy idea is to put a bass speaker on the floor and use a frequency generator, which i have at home, to sweep all the frequencies to the speaker. With my behringer measurement microphone I could try to find the point with the biggest amplitude. Isn't that my resonance frequency? Ok the resonance frequency of the floor should be 4 octaves lower then the frequency i want to isolate. So if there IS any resonance when turning the potentiometer from 33-250Hz (thats the range of the bass speaker) I should definately throw the floating floor out of my studio.
Crazy Idea... just tell me that iam wrong.

The calculation formulas are any thing else than simple. Iam not a mathematician. Doing the wrong calculations causes a wrong resonance frequency and a useless or even an inferior floor as I understand correctly. I can't ask anyone to do the calculations for me nor do I know a source of an easier spreadsheet do to the calculations myself. And I don't know if it would ever be possible to make a working floating floor with joists, mineral fiber insulation, plywood and MDF. I can't buy heavy iron plates to get a heavier mass. It would be easier to do a conrete floating floor like Paul. Also when Paul paid over 2000€ just for the sylomer for his studio I have to pay MUCH more. Because this is only a crazy hobby project my budget is limited of course. Removing the existing concrete floor to make a concrete floating floor isn't possible for me i think. The existing concrete floor is 15-20cm thick and it is so damn hard! If it would be screed no problem... but concrete... I tried to make a hole for the water conduit and the drain with a sledge hammer. It lasts 2 hours for a smaaaaal hole.

What do you think... do I need more noise insulation to the outside. Because thats the most important thing to know.

Kind regards and many thanks for being so patient with such a dum guy

Frank.

You say the existing floor is 15-20 CM thick - does this mean that the TOP surface has that much irregularity?

Also, is there a chance you could post a floor plan of your space and specify each wall's layers, materials, etc? Best would be first a plan of the existing space, then a second version of that same plan with your studio modifications added.

While 4 octaves below the lowest note you hope to isolate would be nice, this isn't practical unless you have a LARGE budget and start from scratch. 2 octaves is difficult enough, and that needs a decent floated CONCRETE slab or else a LOT of expensive MDF layers mixed with gypsum layers, etc.

HOpefully you've read the method I outlined for testing materials on the first page of Aaron's Floating Floor thread - with that, it IS possible to find out if your available rubber material would work - although unless you know WHAT the material is, it's impossible to predict just how long it will LAST before decomposing.

Also, is that copper pipe in the pic with the I-beam some sort of drain for a hot water heater, or what? Steve

knightfly wrote:You say the existing floor is 15-20 CM thick - does this mean that the TOP surface has that much irregularity?

Yes. The floor was filled with concrete 'step by step'. A guy with a concrete mixer vehicle? came from time to time to bring some excessive concrete which was too much at other building sites. Same concrete - but nearly free. From the memory my father said it was about 15-20cm. I haven't measured it. I haven't understood why the floor wasn't counterbalanced before that... i have to ask him again.

knightfly wrote: Also, is there a chance you could post a floor plan of your space and specify each wall's layers, materials, etc? Best would be first a plan of the existing space, then a second version of that same plan with your studio modifications added.

Ok. I hope the following drawings will work.



http://www.nrgrecording.de/tempfolder/c ... n_plan.gif LARGE (126kB)



http://www.nrgrecording.de/tempfolder/before_after.gif

knightfly wrote: While 4 octaves below the lowest note you hope to isolate would be nice, this isn't practical unless you have a LARGE budget and start from scratch. 2 octaves is difficult enough, and that needs a decent floated CONCRETE slab or else a LOT of expensive MDF layers mixed with gypsum layers, etc.

Ok. I can't value the difference of 2 or 4 octaves. But LARGE budget doesn't sound that good.
Concrete is cheap here if you DIY. For the recording room i bet it will last weeks in front of the concrete mixer depending on the thickness. I have to thing about it... I hope the 15-20cm concrete floor will work with a floating concrete floor on top+people, walls... Whats is the approximately popular concrete thickness?

knightfly wrote: HOpefully you've read the method I outlined for testing materials on the first page of Aaron's Floating Floor thread - with that, it IS possible to find out if your available rubber material would work - although unless you know WHAT the material is, it's impossible to predict just how long it will LAST before decomposing.

Yes I'd read it. A very good information. It seems to be tricky. I'll try to figure out what the material actually is. It is made for resting tons on top of it... but who knows how long...
I bet when the floor is finished I will know some sources to get sylomer for free... typically I will try to check out the costs of these sylomer stuff of Stef's link in germany. thanks stef!

knightfly wrote: Also, is that copper pipe in the pic with the I-beam some sort of drain for a hot water heater, or what? Steve

Yes. There will be a heater in the control room. The idea was to install a flexible connector between the recording room and the control room to prevent an acoustical coupling between the rooms.
Hmm... is there a reason why I haven't seen a heater in a pro studio?
I had wantonly negligent thought about using a standard heating device in the CR.


The more I read... the more I feel I did everything to make it wrong.

Will the floating concrete floor be so inescapable to absorb low frequencies? Although when the next neighbours are that much away? I bet it will cost for a CM and RR floor is too expensive for me in with this amount of space. From experience what do you think the cost will be, roughly for each m²?

Many thanks!
Frank.