+1 on heetsheets. Here's a review I posted a few years back:

"I used a Heetsheets single under my sleeping bag for the week. I paid no attention to the various twigs, stickers, pebbles, etc. on the ground before laying it down. There were numerous pinholes by the end of the week, but no other problems resulted. I did not rig it as a fly, though.

On the first night I managed to tear a hole in it by grinding my boot heel into it while putting on boots and gaiters. I intentionally ignored it, though, and left it unpatched. It did not tear or spread a bit.

It was also rather breezy at night and I saw the edges flap and move about quite a bit, but there was no noise from it. I'm extremely pleased with how well the HeetSheet held up to a full week's rough use."
Gear review