originalmusician
Well-known member
I notice a lot of people recommend fiberglass insulation for building acoustical products such as bass traps etc. The problem with the stuff is it the glass gets in your skin, lungs, eyes, or whatever and also contains craploads of toxic chemicals like formaldahyde, etc that have been shown to cause cancer with prolonged exposure.
I recall reading a book by F. Alton Everest a decade or so ago where he mentioned having acoustically treated a recording studio (I think it was in Africa) with cotton. If I recall correctly, he said that cotton has superior acoustical absorption compared to fiberglass, but he didn't recommend it because it was not readily available in an acoustically consistent form in the U.S.. Well, I don't know, its been a long time ago, but I remember it going something like that anyways.
You know Alton passed away last year at the ripe ol' age of 95, and since he wrote that book (Master Handbook of Acoustics) a few things have changed. So I went over to The Environmental Home Center in Seattle and picked up some cotton insulation batts. http://www.environmentalhomecenter.com/shop.mv?CatCode=PRODUCT&ProdCode=COTTON_INSULATION
After installing these things in the wall I realized how superior to fiberglass this stuff is. This brand uses Borax as a fire retardant and mold inhibitor, so you should use a mask while you install it (it's powdery), but truthfully the borax is extremely non-toxic. It just gets in the air a little while you work with it. Once it is in place and covered, it stays put.
Edit: This brand is a little spendy: http://www.soundprooffoam.com/quiet-batt-insulation.html Personally, I like my R-21 stuff and it costs a lot less but the site provides some acoustical data on the R-19: http://www.soundprooffoam.com/pdf/Quiet-Batt-Insulation.pdf
From my experience this stuff is superior to fiberglass batts in every way except cutting it. But if you use the recommended tools (or just by the special saw for cutting it) you will have no problems there either. Personally, I just used a regular hand saw, and it worked fine.
Oh, yeah, if you do a web search, you'll find cotton batts are available pretty much everywhere these days.
:grin:
I recall reading a book by F. Alton Everest a decade or so ago where he mentioned having acoustically treated a recording studio (I think it was in Africa) with cotton. If I recall correctly, he said that cotton has superior acoustical absorption compared to fiberglass, but he didn't recommend it because it was not readily available in an acoustically consistent form in the U.S.. Well, I don't know, its been a long time ago, but I remember it going something like that anyways.
You know Alton passed away last year at the ripe ol' age of 95, and since he wrote that book (Master Handbook of Acoustics) a few things have changed. So I went over to The Environmental Home Center in Seattle and picked up some cotton insulation batts. http://www.environmentalhomecenter.com/shop.mv?CatCode=PRODUCT&ProdCode=COTTON_INSULATION
After installing these things in the wall I realized how superior to fiberglass this stuff is. This brand uses Borax as a fire retardant and mold inhibitor, so you should use a mask while you install it (it's powdery), but truthfully the borax is extremely non-toxic. It just gets in the air a little while you work with it. Once it is in place and covered, it stays put.
Edit: This brand is a little spendy: http://www.soundprooffoam.com/quiet-batt-insulation.html Personally, I like my R-21 stuff and it costs a lot less but the site provides some acoustical data on the R-19: http://www.soundprooffoam.com/pdf/Quiet-Batt-Insulation.pdf
From my experience this stuff is superior to fiberglass batts in every way except cutting it. But if you use the recommended tools (or just by the special saw for cutting it) you will have no problems there either. Personally, I just used a regular hand saw, and it worked fine.
Oh, yeah, if you do a web search, you'll find cotton batts are available pretty much everywhere these days.
:grin: