Rigid Insulation Questions

[Doowah]

As part of my continuing education since joining this most excellent forum, I've recently come to the realization that I'm gonna need to install some sound treatment in my 12' x 10' x 8' (ceiling height) little box of a spare bedroom home recording studio. So, I've followed all of the recent and past threads on this forum regarding the subject of room treatment, and I've read everything that I could find that was written by Ethan Winer on the Internet. I think that I need to mount several panels of OC703/705 (or equivalents) on my walls to act as absorbers, and build bass traps in the corners of the room using the same materials.

I also see that most folks cover this rigid fiberglass material with some kind of fabric, or build a frame of wood and fabric to put over the fiberglass panels. I'm assuming that the covering is strictly for aesthetic reasons, and that it isn't strictly necessary for the sound treatment to function correctly. Is that a valid assumption, or am I missing some point? If this extra investment in money, time, labor and materials is strictly to make the panels "look good", can I just mount the raw panels in place and forget about it?

Sorry if this is a dumb question, which may very well be the case since the whole concept of room treatment is brand new to me. But if I can get the benefits without fooling around with the fabric covering, it gets me a lot closer to getting this done. (I'm handicapped and physical labor is "difficult", but not impossible.) If I don't care what it looks like, but I can help my room acoustics anyway, that would be super. If I'm nuts, please feel free to let me know (but please take the time to educate me, too).

Thanks!

[Folkcafe]

"I'm assuming that the covering is strictly for aesthetic reasons"
From an acoustic perspective this would be correct but the main reason to cover the fiberglass is to keep the fibers contained. Fiberglass is an irritant, both to your skin and lungs.

I took a audio measurement class at work that involved testing loudspeakers in an anechoic chamber. The chamber environment was exposed rigid fiberglass but keep in mind, I didn't spend hours inside mixing audio. Just set up speakers and measurement equipment.

I used hot melt glue to fasten the fabric when I built my studio but if I were to do it again I would probably go with spray adhesive. I might even try hardening the edges like with the commercial panels I purchased in the past.

Don
Folkcafe

[studiogenocide]

Another thing I might add about the fiber retention of the fabric, is make sure you get some good fabric to cover your panels and traps with. You would be surprised how those little fibers freely come off the insulation with NO air circulation in the room. As I was installing them, I could see them in my overhead lighting- it looked like a dusty old barn with the sunlight shining through the windows... Make sure they are covered well.

[Doowah]

Originally Posted by Folkcafe

"I'm assuming that the covering is strictly for aesthetic reasons"
From an acoustic perspective this would be correct but the main reason to cover the fiberglass is to keep the fibers contained. Fiberglass is an irritant, both to your skin and lungs.

Originally Posted by studiogenocide

Another thing I might add about the fiber retention of the fabric, is make sure you get some good fabric to cover your panels and traps with. You would be surprised how those little fibers freely come off the insulation with NO air circulation in the room. As I was installing them, I could see them in my overhead lighting- it looked like a dusty old barn with the sunlight shining through the windows... Make sure they are covered well.

Hmmm. Not good. I certainly don't want to infest my studio area with a plethora of fiberglass particles floating in the air. That might damage my equipment!

Seriously, I guess that I'll have to make the extra effort to use fabric on my panels to prevent the nasties from propagating. I'll just need to figure an easy way to accomplish this with a minimum of effort. Any suggestions?

Thanks again!

[mixsit]

These guys have ready made bags.

http://www.readyacoustics.com/index....&products_id=4

[Weasel9992]

Originally Posted by Folkcafe

"I'm assuming that the covering is strictly for aesthetic reasons"
From an acoustic perspective this would be correct but the main reason to cover the fiberglass is to keep the fibers contained. Fiberglass is an irritant, both to your skin and lungs.

Yeah, that's the right answer. It's not going to kill or or cause cancer, but man...you don't want fiberglass on your hands, arms, in your nose or your mouth. It itches like crazy.

Frank

[Chili]

Yup, definitely want to put some fabric on them to keep the particles from escaping. Supposedly they're harmless, but they are annoying.

I used lightweight fabric I found at the Walmart $1 bin. It's light polyester blend or something. Look for the stuff you can easily blow through, but not see through. Basically, you want the weave to be smaller than the particles. A lightweight fabric will ensure the sound gets through and absorbed without being reflected back into the room.

I used spray on adhesive. I'm having problems with some coming off 8 months later, but maybe those are the panels where I was running low on adhesive.

Just hanging the stuff up is such a huge improvement. It's the best bang for the buck to improve your mixes. And it doesn't have to be expensive or complicated.

[Weasel9992]

Originally Posted by Chili

And it doesn't have to be expensive or complicated.

Amen.

Frank

[Doowah]

Originally Posted by mixsit

These guys have ready made bags.

http://www.readyacoustics.com/index....&products_id=4

Yeah, I scoped those out. Looks like they solve the "make it easy to do" part of my problem, but they are too expensive for what money I have to spend versus how many panels I'll need. Thanks for the suggestion, though, because it made think a little harder for a solution.

Originally Posted by Weasel9992

Yeah, that's the right answer. It's not going to kill or or cause cancer, but man...you don't want fiberglass on your hands, arms, in your nose or your mouth. It itches like crazy.

Frank

I hear you loud and clear, Frank!

Originally Posted by Chili

I used lightweight fabric I found at the Walmart $1 bin. It's light polyester blend or something. Look for the stuff you can easily blow through, but not see through. Basically, you want the weave to be smaller than the particles. A lightweight fabric will ensure the sound gets through and absorbed without being reflected back into the room.

I used spray on adhesive. I'm having problems with some coming off 8 months later, but maybe those are the panels where I was running low on adhesive.

My girlfriend also suggested Walmart for the fabric, as opposed to a fabric shop, and I'll definitely check them out. I've come up with a simple design that should not take a lot of effort, and I think that I can handle it. I figure that the OC703/705 will be the most expensive part of the bill of materials for the project and I can get that at a reasonable price here in Phoenix. So, it shouldn't be too expensive overall. I'm going for bass traps in all the corners, as well as several high freq absorption panels on the ceiling and walls (making sure to mask the "early reflection points" for the monitors).

Chili, I was planning on using spray adhesive, too. Did you spray it on the entire fiberglass panel (including the front), or just on the back to keep the fabric adhering to the panel? I guess my real question is whether or not the use of spray adhesive on the front of the panel will interfere with its sound-absorbent qualities? I was going to avoid using it all over the panel because I feared that it would cripple the effect. If that is an incorrect assumption, I can simplify my project considerably. Please advise...

Originally Posted by Chili

And it doesn't have to be expensive or complicated.

I believe that was my REAL problem I always tend to over-think, over-analyze, and over-complicate everything!

[dodgeaspen]

Puke-Mart has a lot of sales on fabric. That will be good to keep cost down. Post some pics your done.

[Doowah]

Originally Posted by dodgeaspen

Puke-Mart has a lot of sales on fabric. That will be good to keep cost down. Post some pics your done.

I certainly will post some photos when it's complete!

[Chili]

Originally Posted by Doowah

Chili, I was planning on using spray adhesive, too. Did you spray it on the entire fiberglass panel (including the front), or just on the back to keep the fabric adhering to the panel? I guess my real question is whether or not the use of spray adhesive on the front of the panel will interfere with its sound-absorbent qualities? I was going to avoid using it all over the panel because I feared that it would cripple the effect. If that is an incorrect assumption, I can simplify my project considerably. Please advise...

I started out spraying the complete front and wherever the fabric covered the back. When I started running low, I stopped spraying the front and then maybe not the complete back. That might be the panels I'm having problems with. I suggest getting two or three can of spray-on adhesive. It goes on as such a thin layer, it won't affect the performance of the panel any more so than the fabric.

In regards to the OC703, I suggest you also consider the Johns-Manville Fibreboard also. It is very similar to OC703/705 in size and density, but it's not flaky like 703. I had the opportunity to compare side by side and next time I will only buy the JM stuff.

Buried a few pages down, I have a thread where I showed some pics and discussed the differences. Maybe search this forum for any posts I started. You should be able to find it easily that way.

[Doowah]

Originally Posted by Chili

I started out spraying the complete front and wherever the fabric covered the back. When I started running low, I stopped spraying the front and then maybe not the complete back. That might be the panels I'm having problems with. I suggest getting two or three can of spray-on adhesive. It goes on as such a thin layer, it won't affect the performance of the panel any more so than the fabric.

In regards to the OC703, I suggest you also consider the Johns-Manville Fibreboard also. It is very similar to OC703/705 in size and density, but it's not flaky like 703. I had the opportunity to compare side by side and next time I will only buy the JM stuff.

Buried a few pages down, I have a thread where I showed some pics and discussed the differences. Maybe search this forum for any posts I started. You should be able to find it easily that way.

Thanks for info. Spraying the front of the panel will certainly help the fabric stay "stuck", and it makes for easier construction compared to my original plans. As for the JM substitute material, I will definitely check into it.

Muchas gracias, amigo...