Well, like I said before I shouldn't be able to find any sili-nylon so that idea's out.

I've camped in a hammock a lot and yeah, the usual deciding factor for staying warm is what pads to bring and how many, to put inside the hammock.

But, I reached a point where pads were not enough to keep me warm so I had to put a fleece liner inside my sleeping bag and that cranked the heat up enough for me to be comfortable.

If it gets seriously cold though, like below 10F, I can't see a simple fix other than dishing out for a new bag or trying out a tent or something. I don't want to do either, but if it stays pretty cold on the mountain I don't see any other choices.