Owens Corning 703

I am using this material to build out a music room in the basement - I have glued/tacked 1 inch sheets to my open ceiling between floor joists. My designer has suggested covering the ceiling with cloth to use the whole ceiling area as diffusion.

My question is will this keep fiberglass from floating around since there will be approx 5 inch gap between the fiberglass and cloth? I know most applications for bass traps for example, involve adhesion of the cloth to the fiberglass board...thanks.

Your designer is on the right track. However, what you describe results in an absorber, not a diffusor. And, it will be a pretty big one at that. Moreover, it will not likely work at very low frequencies since it is only 1" thick and it is placed against the floor above.

Generally, thicker material is required for bass trapping and it is best to space the material off the room surface.

Further, I'd begin to get a bit concerned about the room becoming too dead sounding....

I don't think you need worry about the fiberglass though.

If you read the Studio description on my website - there's some hints there. Also, feel free to give me a call if you need more help.

Can you add a filler material? That would certainly dampen reflection and achieve your goal.

Thanks for your response and your studio is beautiful - I have viewed it many times as a reference.

The "trap" above me is more for high frequency damping with regards to the 703 on the ceiling - I have several 1" by 5" boards between each joist at 30 degree angles - towards the front of the room which actually act as a diffuser. So I think it accomplishes both objectives - high frequency damping and diffusion.

I am building floor to ceiling bass traps in 4 corners of the room.

My contractor is concerned about the fiberglass, so now he has me thinking!

Thanks for posting your experience with your room - it must sound awesome.

Some trap builders use a sheet of plastic or fine woven cloth over the fiberglass. That does affect the absorbancy to some degree but not sure how much. Then, there's the fire rating...

Is there a health concern? Didn't use to be about asbestos either. Now there are rising concerns about silica (cement). Maybe, breathing air causes cancer.
Good point Ngjockey....whats bad for you today is good for you tomorow and vice versa!
The owenscorning will stay in place unless phsically disrupted . A fabric will look best and would trap any loose particles if for any reason it got disrupted .
thanks maplegrovemusic
Try rock wool instead of fiber glass, products such as Roxul Safe n'Sound. The rock wool is less of an iretant than fiberglass.

As for facing materials, for my bass traps I bought fabric from Ikea and used it to cover the Roxul. Just be sure that the material has a tight weeve.

For my ceiling I do the following, I suspended two layers of insulation between the joists and left an air gap between the insulation and floor above. The first layer looking from below is a 3/4" thick fiberglass ceiling panel which is faced with a thin dimpled sheet of plastic. The plastic provides a clean surface for the ceiling. The second layer is 3" thick Roxul. check out my system picks to see the end result.

This has deadened my room substantially but, my room is small and it needs it.

I hope this helps
Thanks Nick, nice room. i have a large space in my basement, alot of area to treat. 703 is already tacked/glued between the joists - the is a Rives design, hopefully another 30 days it shoud be complete - been working on it since March...
Good luck with completion of the project. I hope you post some pics in your system page when it's done.
I would not hesitate to cover your entire ceiling with cloth to prevent any loose material from falling your way. I have been in the insulation business for over 40 years and you don't want any insulation fibers falling your way. They also make metal rods to help support the insulation. They are inexpensive, probably 20 dollars for your room, and extremely easy to install, just place between the studs and they are made pre cut to almost any size you need. The glue will loose adhesion over time so you should do something more to keep the insulation in its place. Owens Corning 703 is fairly rigid so I believe you will be fine if you cover the ceiling with cloth. Good Luck and make sure to post some pictures when your done.
Thanks Needfreestuff, that will be my plan. will be happy to post pix...if this project ever gets finished!