Insulation, Radiant and Vapor Barriers - attic insulation

I've been re-doing my closet, which is under the roof soffit. When I removed the plaster and lathe on the ceiling part, I was buried under a mass of black and white fiber stuff. I'm told this is a type of blow-in insulation. What, exactly, is this stuff? It was very itchy, and I got a face full of it. The reason I was re-doing the closet, besides trying to improve storage, was to insulate it. I'm only in this house about 6 months, and I've been unable to use the closet all winter because of the cold air coming out of it. I think I can handle insulating the closet, but I was going to insulate the attic crawl space, as well. Should I just add over top of this stuff? Is it adequate by itself? I really don't want remove it. I also have to break through the ceiling to get to the crawl space, so if this fiber stuff is up there, too, should I replace the fiber I remove with fiberglass insulation cut to fit the space of the fiber I removed?

but I was going to insulate the attic crawl space, as well. Should I just add over top of this stuff? Is it adequate by itself? I really don't want remove it.
You can go over what is there . Most of the time they say about 12" deep on the insulation for the attic now. You dont want and paper or V/B on the new insulation you add up there on top.


I also have to break through the ceiling to get to the crawl space, so if this fiber stuff is up there, too, should I replace the fiber I remove with fiberglass insulation cut to fit the space of the fiber I removed?

Yes so its like the rest of the attic. ED ;)