but did you notice if it was happening over a wide area or did you by chance just see dripping from certain places, like near seams?
It was happening over a wide area on both of our tarps. I don't think these are silnylon. Per mosquito hammock's website "Made of waterproof Nylon Tafta (210T)". Like I said, it took a while before it started leaking. It wasn't pouring under the tarp, but if I was in the wilderness, it would have caused us problems because things were starting to get wet.