I am currently working on demoing our kitchen and am not sure how to proceed. I recently did our bathroom and for the floor I left the old backerboard, chiseled remaining thinset, applied a self-leveling compound. For the kitchen there was a lot of thinset that didn't come off with the tiles so I was thinking of just replacing the backerboard.
However, there is this material between the backerboard and the subfloor that I'm concerned about.
Does anyone know what this is? It seems like it's some kind of fiber. Could it be a mat, felt, thinset, or adhesive? My main concern is that it contains asbestos.
Some more info: The house was built in the 1930s. The kitchen seems to have been remodeled somewhat recently (the tile I ripped out can be found at Home Depot). I'm not sure if the material is some kind of mat to reduce creaking or if it's really old and the previous owner left it there and just covered it with backerboard.
Any insights or suggestions on how to proceed would be greatly appreciated!