I know that the ABS main stack in my home is not rubbing against the floor or attic plywood openings; it is rubbing against the drywall in a interior wall when the pipe expands with the use of hot water. The pipe is 3.5" in diameter and the wall is studded out with 2x4's, so the stud bay is 3.5" as well. With such little room to add felt, I was hoping a product existed that was thinner but would still eliminate the ticking noise.
Does any sheet-like product for this application exist? I was expecting to find some sort of two-piece sheet system that would allow the sliding to occur between the sheets but I have had no luck in finding such an item on the interwebs.