I have always carried a Tyvek sheet and put it under the Serenity. I have never even questioned why I do it – I just always have. I was just looking over my gear list and saw the weight I carry for it and decided to pose the question to y'all.
Do you do the same? Is it worth the 4.6 ounces? Is the serenity bottom waterproof on its own? If you think a ground sheet is indeed a good idea, do you know a lighter and just as durable option?

