I made a silnylon pancho with a Goretex hood from a Quest Outfitters pattern. It is the large style to cover one’s backpack. With side snaps and sealer around the hood it weighs 12 oz. If you hike hot like I do, be wary of silnylon because it does not breathe. I hoped that the GTex hood would be breatheable enough,given the side venting, but it was/is not. I have carried and left it home. Last trip out I used it for a groundsheet with the Ray Jardine inspired silnylon tarp that I sewed years ago. (the tarp still works great.) If I was sleeping out of level, (lots of out of level sleeping on the AT in NC) it was like sleeping on a greased cookie sheet; me and my pad slid right off. It is plenty waterproof, but if you hike sweaty, you’ll get wet under silnylon. Muleskinner.
Muleskinner