New poster here, but I've visited the forum several times in my research. I've searched through several threads on comparisons between mineral wool and fiber glass, but have a question I wasn't able to find a specific answer to:
I am considering building unframed panels (wrapped in polyester fabric, glued, with bolt/washer and wall hanger attachments (using glue/adhesive around the bolts to bond some rigidity with the fiber glass - maybe a bad idea, but frames are the backup plan).
Is there a difference between mineral wool and (for example), OC 703 - is one or the other easier to work with?
My reason for the question is quite simply the wide range in price:
I can order Owens Corning 703 (2", 2'x4') for about $15/sheet but the same supplier sells 6 sheets of mineral wool board (48sq ft) of 2" mineral wool panels for only $29. Why the large price difference - just the nature of fiber glass vs. mineral wool in general? If mineral wool disintegrates more easily, I would probably go with fiber glass simply for sake of convenience. If there is no difference, price wins.
The mineral wool seems to be 8lb density, where I was mainly looking at 3lb density fiber glass boards. The rep I called was fairly helpful with describing the differences, but wouldn't give their own opinion on the difference.
Thanks!
Mineral Wool vs. Fiber Glass - workability
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kdm
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knightfly
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For some reason (probably manufacturing cost) mineral wool is always cheaper; absorption, given same density, seems to track nearly identical between the two.
However, you're talking about 8 PCF instead of 3 PCF; for all but 90 degree incidence, there's a high probability that the higher density stuff won't absorb as well at higher frequencies; it's too dense, so instead of "soaking in" at an angle, the sound tends to reflect causing a lower absorption coefficient at these higher frequencies.
One way around this (sorta) is to put some NORMAL density fiberglass (or some types of polyester) insulation in FRONT of the 8 lb. rockwool; this gets into a "sandwich" thing though, and makes construction less straightforward.
Handling-wise, the rockwool is usually stiffer (especially 8 PCF) and scratchier, but for frameless mounting it would retain its shape better.
Performance-wise though, I'd try to find some lower density rockwool or do the front cover thing I mentioned - exceptions might be if your room is already dead enough in the high end, then the 8 lb. stuff may be just what you want... Steve
However, you're talking about 8 PCF instead of 3 PCF; for all but 90 degree incidence, there's a high probability that the higher density stuff won't absorb as well at higher frequencies; it's too dense, so instead of "soaking in" at an angle, the sound tends to reflect causing a lower absorption coefficient at these higher frequencies.
One way around this (sorta) is to put some NORMAL density fiberglass (or some types of polyester) insulation in FRONT of the 8 lb. rockwool; this gets into a "sandwich" thing though, and makes construction less straightforward.
Handling-wise, the rockwool is usually stiffer (especially 8 PCF) and scratchier, but for frameless mounting it would retain its shape better.
Performance-wise though, I'd try to find some lower density rockwool or do the front cover thing I mentioned - exceptions might be if your room is already dead enough in the high end, then the 8 lb. stuff may be just what you want... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
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kdm
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- Location: Colorado Springs, CO