Loose cellulose

[Old Goat]

I've searched and looked and read and can't find any info on cellulose insulation. I was thinking it might be a good sub for fiberglass in filled corner traps--cheaper, easier on the lungs, etc. I checked Bob Gold's page, and apparently that's the only substance on the planet he doesn't have numbers for. All I've found is a reference to about 2#/cu ft when blown in. Anybody?

[jwl]

I've never seen specs on cellulose for audio absorption. I've never worked with it myself. All I can offer is vague reports by unreliable sources (read: various acoustics forums on the Internet.... ) that it doesn't work.

Until proven otherwise (when someone finds specs for it), I have no reason to believe that it provides any benefit acoustically.

If you are looking for something that works acoustically and is easier on the human body that fiberglass, try Ultratouch cotton.

[jaykay]

I think most cellulose insulation has a really high gas flow resistance which makes it pretty bad for bass traps and such.

[Old Goat]

I'll call that case closed. Thank you, gentlemen.

[svart]

i'd read somewhere that cellulose was actually better than fiberglass.. I think we need to reopen the case..

[avare]

Originally Posted by Old Goat

I've searched and looked and read and can't find any info on cellulose insulation. I was thinking it might be a good sub for fiberglass in filled corner traps--cheaper, easier on the lungs, etc. I checked Bob Gold's page, and apparently that's the only substance on the planet he doesn't have numbers for. All I've found is a reference to about 2#/cu ft when blown in. Anybody?

Cellulose insulation is also known as cotton. could you link the 2#/ft^3 data you found? Then Bob can include it on the list.

I did a quick check and what I found was Thermocon Tex Cell Spec. Basically, the datasheet shows what is generally known about cellulose. It is roughly equivalent to glass fiber and mineral fiber insulation.

Go for price, checking here to make certain the product doesn't have any gotchyas.

Andre

[Old Goat]

Here's one;

GreenFiber.com || Fact Sheet - Homeowners

Check the footnotes.

There is also information about Transmission Class Rating, but I don't know if that means anything inside the room.

[avare]

Thanks for the link. As you wrote STC is meaningless for absorption in the room.

Andre

[vipunen]

Originally Posted by avare

Cellulose insulation is also known as cotton.
Andre

I don't think so!tutt

At least here in Finland the Cellulose insulation is made of recycled paper.
I believe it´s exactly the same stuff you have in states.

I getting truckload of this stuff next week for insulating my house.
And I would definitely like to know some FACTS about it's acoustic properties...

[avare]

Originally Posted by vipunen

I don't think so!tutt

At least here in Finland the Cellulose insulation is made of recycled paper.
I believe it´s exactly the same stuff you have in states.

The names used in different parts of the world change. On a different absorbent material the proper term for all of the following is mineral wool:

fiberglass
rockwool
roxul
glas wool
basalt wool

yet in some parts of the world some have different meanings. Making it even more confusing, Roxul sells two products with the same name in Canada and USA!

Green fiber, blown in cellulose, cotton insulation, denim insulation, are all cellulose based insulation.

I getting truckload of this stuff next week for insulating my house.
And I would definitely like to know some FACTS about it's acoustic properties...

company links, density of the material, will all help. If you are putting it in the partitions, then the acoustic properties are not significant. It will work at reducing the sound transmission.

Andre

[vipunen]

Originally Posted by avare

The names used in different parts of the world change. On a different absorbent material the proper term for all of the following is mineral wool:

fiberglass
rockwool
roxul
glas wool
basalt wool

yet in some parts of the world some have different meanings. Making it even more confusing, Roxul sells two products with the same name in Canada and USA!

Green fiber, blown in cellulose, cotton insulation, denim insulation, are all cellulose based insulation.

company links, density of the material, will all help. If you are putting it in the partitions, then the acoustic properties are not significant. It will work at reducing the sound transmission.

Andre

Oh, OK... I thought cotton wool is made of cotton!!!

I don't want any more of glass/rock wool in my house, doesn't matter what it's called! (I have old log house, and I wan't to keep it breathable).
+ I'm into ecological materials...
But if it's only reasonable solution for bass traps, I might use it there.

In Finland we have at least 3 companies selling cellulose wool. I believe all brands has exactly the same product.
Density is around 35kg/m3. But with this stuff you can easily double it by just pressing it tighter.
I Think when building basstraps or similar you can pretty much get exactly the density you want...
Airflow is 90 - 135.
http://www.selluvilla.net/txt/sertifikaatti.pdf

By "partition" do you mean the space between the wood frames???
(...sorry, I'm not native english speaker...)
I have that kind of constuction in second floor, where my homestudio is going from our living room.(thank god!!!
All walls are wood panel.
In front and back walls there's 8 inches of glass wool (recycled).
Behind that again wood and then 2-6 feet airspace. then theres only angled tile roof before outdoor.
Side walls are 6 inches of cellulose.
The room is quite low, only 7,38 feet. roof is again wood panel and behind that theres 1.5 feet of cellulose.
Other dimensions are W = 14, L = 20,24 ...I just realized that width is about double the hight and lenght is close to triple the hight!!! not good, right???

btw,
What you think, does the bass frequencies bounce from 1 inch wood panel, or does they go right through?
What if there's holes in wood panel?