So I just ordered another box of rockwool from the same place as the last box but when I opened the box it was completely different. The new stuff has kind of a greenish color and seem alot less rigid. The first box was a yellowish color and fairly rigid ( you could put the ends on saw horses and it would probably lay flat.) So after looking at pictures I started thinking maybe they sent me 703 the first time by mistake. But with it being so rigid I'm starting to wonder if it could be 705 which would make a difference in how I use it. I just haven't worked with this stuff before so I don't know how to indentify it.

Lance

703 pic


Mineral Wool

Hey thanks for making it simple. The second pic looks like what I just got but I'm not sure my other stuff bends like the first pic. How easy is that bending?

That first pic looks like a ceiling tile with a OC backer about 3/4" thick. The 2" 703 does not bend like that.

Agreed - but the two pics do give you an accurate idea of the colors of the materials.

703 or 705 are called 'rigid fiberglass' and stand up on their own (i.e., are rigid enough to make 'unframed' panel traps with fabric cover but no 'skeleton'), while mineral wool / rockwool is 'floppy' and would need to be in some sort of frame to avoid looking 'droopy' and 'baggy'.

Mineral wool pic I took myself, so my word for it being what it is. The other pic is from Ethan Winer's site & it looks like 1" rigid fiberglass as far as I can tell, the source is pretty reliable too