John Sayers' Recording Studio Design Forum Archive

Hi there everybody
i'm just about to begin constructing my basement studio in Thessaloniki Greece (here is my design thread: http://www.johnlsayers.com/phpBB2/viewtopic.php?t=8898 )
I'm planning to float the floors in all the rooms. The problem is that i can't find products like Sylomer or Kinetics here in Greece and even worse there is probably no one with experience on these products and on the calculations needed to be done for them to work correctly as a MSM system. So i decided to build floating concrete floors on rigid mineral wool panels. I read all posts i found here and at studiotips regarding this kind of construction, and allthough i understand that this is not the best sollution regarding music spaces due to the higher MSM resonanse freq, i think it is the only way to do it proper over here.
As i get it fiberglass is much better than rockwool because it allows more deflection under load. Mr. Desart wrote a lot of interesting things about that:
http://forum.studiotips.com/viewtopic.p ... ting+floor
http://forum.studiotips.com/viewtopic.p ... ting+floor
http://forum.studiotips.com/viewtopic.p ... ting+floor
So what i underastand is that deflection of 10 - 15% of the "spring" would lower the resonance frequency of the MSM system enough for musical aplications right?
So my(one of 1000 ) question is: How can i calculate the deflection of the fiberglass panels? Can i use the technique that it was pointed on the drum riser post on this forum: put load on a fiberglass panel until it reaches the desired deflection? and if so, in what scale should i perform this experiment in order to get a practical result? would a 1 m2 panel work.
On my floor i'm planning to use 10cm of 80-100 kg/m3 fiberglass and reinforced concrete upon it.
please, i need your help on this
Nikodemos

I honestly think that you're risking wasting your time and money on a floor that may cause the entire space to be isolated worse than if you don't attempt to float at all.

Please study the "Is a Floating Floor Right For You? Answer: Probably NOT" sticky thread.

--Keith

Hi there Keith....believe me i've read this thread more than 10 times....but you see concrete buildings here in Greece and in EU in general are a very different thing from most US structures. The steel reinforced concrete foundation walls go all the way from bottom to top providing an excellent path for sound to travel through, from the basement right to the top floor of a 4 floor building.....so believe me floating the floor is a must in such a building......the problem is how to do it right
I have read almost any info i could find on the net and on some great books regarding this matter but still.....there are several things to consider:
how to do it, where to find the materials, can you find them?, what would be the cost etc etc....from all my research i found out that floating a concrete floor on minerall wool is probably not the best sollution.....actually the worst regarding resonanse frequencies of the MSM system to be build......but it is in my price range, i can easilly find the materials, and most important i can find experienced workers for the construction. Also from what i've read it is probably possible to build a m.wool - concrete floating floor with a more "musicall" - lower resonanse frequency......and that's where help is needed.......to find a way to calculate the MSM frequency of such a construction. On Newells and Everest books this kind of floating floors seem to be a "standard" but no one describes "how to do it" and "why to do it that way" or "what to expect from it". And i guess that since there is not enough data on certain aspects of mineral wool(over lots of different brands) like deflection specs, deflection over ageing etc, there is not a standard calculation form either.

so it would be great if mr. Desart (since most of what i've found on the subject comes from him - mr.Desart please find the time to write a book it would be a great gift to all of us ) and mr.Sayers (who designed such a floating floor on the SAE website) could give a little guideline on this matter.
I'm sure that this construction - thread would be very interesting for all the EU members of this forum.
thanks in advance for all your help
Nikodemos

Nikodemos,

There are representatives of Sylomer in Greece as well:
http://www.getzner.at/werkstoffe/print/ ... =en&id=133

Search the web or email them. The base producing company of Sylomer is Getzner in Austria.
All these representatives (35 countries) have the necessary software to calculate this stuff for you.

For glassfiber do you have Isover (or other brand) there? If they allow a 10 % deflection in function of material load, you can use it.
Call them and ask for floating floor boards. (provide links).

If you can provide a link (English, not Greek) I look into it.

If you can find a distributor of "bonded foam", as I recently learned sometimes also called "chip foam" or agglomerated foam this works also and can used as substitute for fiberglass.
That's this recycled grinded and bonded foam with these foam chips in them. In fact this foam has better acoustic properties (ratio deflection/MSM) than mineral wool, it's used a lot here for that purpose, but it hasn't the aging and moisture resistance properties of Sylomer.

I'm still not convinced though. Maybe you're right, but the facts you have identified don't make for an absolute unarguable case that you must float a floor for effective isolation.

If you were going to build on an upper floor, then yes, I would tend to agree.

If you are absolutely convinced that a floating floor is necessary, then I recomend the jack-up concrete slab system, by either Mason Industries or Kinetics Noise Control... Although even they will acknowledge that those systems are intended for impact noise control, not airborn. They can assist you with the calculations as well.

I seriously considered the Mason system at one time... But a local acoustical engineer told me it wouldn't be necessary. I also had seismic issues to consider that would have made it challenging to get through buiding department approval without a structural engineer's certification.

--Keith

Thanx for your response mr. Desart
i am aware of Greek sylomer dealers....the problem is that they never responded to my emails and calls for the past 2 months....and that's typical for Greece (That goes for Kinetics too...
Anyway i'll keep trying to reach them but i certainly don't trust them...
Regarding Isover fiberglass i found a few importers here in Greece, not plants. All info i found was some pdf in Italian
it has this: dimension tolerance:
lenght:+ - 10mm
width: + - 5mm
thickness: 3mm
for a 85kg/m3 20mm board....is this deflection? if it is....then 3mm deflection on a 20mm board is 15%, right?
should i look for something like this? and if so what is the optimum thickness for fiberglass panels in such a floating floor?
I'll do some research on the foam now
thanks so much for your help
Nikodemos

sharward wrote: If you are absolutely convinced that a floating floor is necessary, then I recomend the jack-up concrete slab system, by either Mason Industries or Kinetics Noise Control... Although even they will acknowledge that those systems are intended for impact noise control, not airborn. They can assist you with the calculations as well.

This are certainly good companies as well.

Nikodemus just info:
Found this one, but don't know if it's the main dealer:
http://www.ergoakoustiki.gr

Keith,

Have you compared systems that you are so absolute in your advice?
Have you practical experience with them, and/or others?

sharward wrote: If you are absolutely convinced that a floating floor is necessary, then I recomend the jack-up concrete slab system, by either Mason Industries or Kinetics Noise Control... Although even they will acknowledge that those systems are intended for impact noise control, not airborn. They can assist you with the calculations as well.

Keith,

the mason industries jack up systems are designed and tested for air borne transmissions as well as impact noise - and are recommended specifically for sound studios.......

I think you are confusing the Mason Industries literature on wood elevated decks with their jack up slabs............

BTW - you know what I love about Mason Industries?...... they don't patent anything they design for the market place - they actually encourage their competitors to use their designs..........


Sincerely,

Rod

Nikodemus

I see now that our post crossed.
It's often a problem to get more industrial oriented companies interested in private persons (function of quantities, and not being organized as such).

Try an email to Getzner itself, play dumb, tell that the studio people on the net advices their material and ask for a local supplier. If they give you a reference, you can tell that supplier you're directed by Getzner itself to them.

They're often more sensitive not to harm there good name versus their supplier, than what they consider small turnover with a lot of blah-blah.

About that wool I want to check myself what they write about it. Don't you have a type or code number (maybe easier to find on the net)?

I haven't checked your plans now. But if you just use it underneath floating floors without walls being build on top of them, fiberglass and foam is maybe worth investigating further (cheapest manners to make floating floors).
If you build your walls on them I should go for stuff like sylomer or the companies mentioned by Keith.

thanks for your response mr.Desart
well, contacting the Getzner directly is probably the best way, i'll send an email right now.....i hope i won't get ignored there too.....after all i just want to spend some money
Actually my plan is to build the inner walls on the floating floor.....do you think fiber glass is a bad idea in such a case because of ageing etc or in generall cannot support a heavier structure?I mean i read in a lot of posts at studiotips that if someone makes the concrete thick enough, lets say 15 cm - 300 - 320kg/m2 then he shouldn't really worry about the walls,people and equipment load on top....do i have it completely wrong?

Anyway i'll try to post the link of the isover pdf or the pdf itself

Keith, thanks for your interest....you are very helpfull
thanks
Nikodemos

Nikodemus,

Have you calculated the weight of your walls already?
That becomes a line load at the perimeter of the concrete.
That means that you have to use either higher densities there or if cut in pieces, a higher number of pieces per surface unit.
What I mean is the resilient material must be adjusted to the load.

Cheaper solutions as fiberglass aren't really documented very well for such more technical applications.

For simple floors where you can count on the load distribution by the topfloor, you can use more stylized cheaper stuff.
If it becomes more technical, I should resort to the more technical solutions designed for such purpose.
You won't easily find people selling you fiberglass, willing to investigate and guarantee this for you.

i was under the impression that if there is a continious underlayment under the concrete the load would spread equally on all surface...no?
anyway i was under the impersion that with a reinforced concrete slab of 15cm the load of the walls would be insignificent.....
i am not a "fiberglass maniac" i just want to have an alternative sollution ready in case my quest for syllomer fails......
i found some info on minerall wool form greek supliers but guess what...it's all in greek so i'll try to contact them and get this info in english...for you to check them when you find some time
i search for this aglofoam but what i seem to find is some thin(3-8mm) rolls for vibration control under wooden or tile floors...is this what we're talking about?(ethafoam,fibran are some brands).....can you point a specific brand to search for in Greece....i mean aglofoam does not provide any return searches in the greek google

Nikodemos

This is (different names I encountered for the same stuff),

Rebonded foam,
Bonded foam,
Chip foam,
Agglomerated foam

http://www.ulgens.com/sponge01/id7.htm

In Belgium it's produced by Agglorex (name related to process) and Recticel.
But that must exist anywhere.
It are the scrap parts of the production of standard open cell polyester and mainly polyether.
Unlike mentioned on the above page they can produce this in higher densities. I've seen them close to 300 kg/m3.
Most of the scrap parts from foam manufacturers (and maybe other sources) will become this kind of foam.
This is produced in blocks and afterwards cut in any thickness. For very thin foam (underlayer), they sometimes glue the ends together to deliver it in rolls.
While it starts which all kind of colors from these scrap parts the production process allows to give the final foam a dominant color, which is often used just to distinguish between produced densities.

Personally I don't know any other typical brand name than Agglorex (not on the net) making agglofoam, since for lots of producers it's just another type of foam, giving it one of the above names (and maybe others), and major dealers can distribute it under whatever own nice sounding name.

It once just started as reclycling for foam in packing. Agglorex got even payed to help other producers getting rid of their scrap.
But since one can give this foam properties one can't get with the original foam it's made off, it got numerous technical applications, making these scrap parts a relative expensive commercial item.

I can't help you finding local suppliers, and have no idea which name you should look for. You must ask a foam guy there.

But be careful. You can look for such stuff, and maybe designing a cheaper floor, IF you know how to handle all this.
I don't think you can count on groups to do this kind of work, which normally costs a multiple of the money you save by not using the stuff which is designed AND documented for this purpose.

If you build walls which are heavy enough to relate to the isolation of your floating floor, you should take that perimeter line load into account.

thanks for all the info mr.Desart....i really apreciate it
i search for bonded foam here in Greece (well on the web) but didn't find anything...so i guess it's not widely used over here...
i'll try to get these sylomer people since as i get it this is the best sollution
...on the other hand i want to get more in to the fiberglass - concrete thing as an allternative sollution
Here is the link for the isover products
http://www.metaxiotis.gr/en_catalog/2/B ... ospect.pdf
as i allready told it is written in Italian but i couldn't find anything in english with these specs.....and i did search!!
i've attached a plan of my structure...the inner walls should waight about 35kg/m2
In a hypothetical case where i've found a fiberglass panel with the proper specs regarding deflection, thickness, density etc do you think that i should use a more dense panel around the perimeter of the room because of the greater load?
My intence is to build the whole thing as good as possible regardless the cost....so i'm not searching for a cheaper sollution but for the best one regarding the fact that i am in Greece....

Nikodemos

I come back to this later.

http://www.isover.com/SiteContent/view.do?navId=72

What is Piano GB. I assume that piano stands for silent, hence some special type (:) or special name) for Gypsum Board?