Re: Does Blown in Cellulose work?

[Bob]

Mike,

 From our experience, the blown in cellulose does not work for soundproofing. I have heard some people testify that it helped a little, but was not worth the money invested as opposed to the soundproofing results. It is good for the thermal value, but this material does not have any mass, which is generally needed for good soundproofing.
 Mike, I sure hope this answers your question.
  
BJ Nash
Super Soundproofing .
Ph: (760) 752-3030
URL: www.soundproofing.org
For orders  (888) 942-7723

[john bergstrom]

I don't have any direct experience with cellulose, but I've read that it is analogous to fiberglass batts.  It has absorbtive qualities that will increase the STC value of a wall (by reducing coupled-cavity-resonance) by 3-6 dB.  That is assuming that the wall is constructed properly, with all penetrations and gaps sealed, which is a BIG "if" in existing construction.  And, in bulk, the stuff is pretty cheap, so it's worth a shot.

[Bart]

I was charged $3000 for my wall by a contractor- did'nt notice any diff.  He said to read my fine print of the contract- a magnifying glass reveals no guarantee.

If they won't specify the results, don't do it.

Black Bart

[johnbergstromslc]

Bart:

See, your wall probably didn't have any kind of sealants and had a lot of gaps and penetrations.  That's why it's better to tear off the old work so you can seal the sucker up before putting in the insulation (if you use fiberglass, you can do the work yourself.)  You can also apply 2 layers of drywall or put up resilient channels to really kill some noise.  

It seems a lot of people think you can just throw something in the wall and magically solve your noise problem.  Obviously not.

[supersoundproofing]

Another reason it doesn't work is that much of the sound is transfered through the studding (joists), which normally being wood, conducts sound quite readily.  (Metal is slightly better at blocking sound).  So putting material in that airspace, even sound control material , doesn't do anything.

Idal wall and ceiling assemblies are discussed at
http://www.soundproofing.org/treatments_for_sound_control.htm

BJ Nash

[skip]

FIbre Glass Insullation has been used for  many years as an effective Thermal Barrier. In recent years it has been used as a sound insullation material. Major producers of Fibre Glass have gotton some good results regarding sound in their test labs. However, in the real world; most Fibre Glass installation leave the purchaser expecting better results.

There are now on both the commercial and do it yourself markets newer and better Sound Insullation Materials.

One of them is Ultra Touch a Product manufactured by Bonded Logic.

[joel]

Here's a quote from the latest cellulose try results i've received:
"I live in Staten Island and had dense cellose packing put into the ceiling it did not work.  Can recommend someone in the staten Island area I can talk to. "