Help!

[OO7Ninja]

I'm looking for a light(ish) weight...breathable waterproof material that can bear 300-400lbs but also prevent moisture penetration if it's on the ground. (like a bivy).

My goal is to make a traditional mayan-style hammock with a ridgeline and a zip-up waterproof shell. That way I don't need a tarp, and my hammock can double as a waterproof bivy when I'm grounded.


Also: I'm torn between sewing it as a bivy with gathered ends and doing it all myself.

OR

just buying the Warbonnet blackbird and modifying it by adding zippers for the liner.

But a premade hammock will probably have a bit of extra hammock material I don't need so doing it myself may help me cut down on the weight. (I'm 5'6)

[FLRider]

Personally, I'd go with a non-breathable groundcloth for those times you intend on going to ground.

My reasoning: sooner or later, you're going to snag that on a rock or root. Since it's a load-bearing fabric body, the next time you hang it (if you haven't noticed the snag), you'll wind up being gravity fed to the ground.

If you bring a rectangular or winter-style tarp (one that can be closed at the ends), you'll have the advantage of making a "tent" on the ground with your hiking poles. Keep the groundcloth smaller than the tarp (this can double as your poncho for weight savings), and you'll have a bug bivvy/rain protection all-in-one ready to roll, no matter where you wind up for the night. You'll also likely want to go with a pad rather than an underquilt for bottom insulation, for obvious reasons.

If, however, you're really tied into the use of your hammock as a bivvy, there are several Gore-Tex fabrics out there that might fit your intended usage. Rockywoods has several mediumweight fabrics that are supposedly WP/B. Note that I've not used any of these myself, so I can't comment on actual waterproofing or breathability. However, the 300d+ range should be abrasion resistant enough for your intended use. I honestly wouldn't go lighter than that, personally, for the above noted snagging issues.

I hope it helps!

[OO7Ninja]

Thank you!

First I thought maybe I'd carry an ultralight bivy with the hammock and use the rainfly for both depending on situation. But, being from Alaska, I forget the rest of the world has crazy poisonous bugs.

I'm currently entertaining the idea of an ultralight inner tent/bug screen with bathtub flooring, with a rainfly that I can also use over the hammock.

I'm not sure how well pitching a hammock with a ground tarp would work in windy conditions.

[FLRider]

Thank you!

First I thought maybe I'd carry an ultralight bivy with the hammock and use the rainfly for both depending on situation. But, being from Alaska, I forget the rest of the world has crazy poisonous bugs.

I'm currently entertaining the idea of an ultralight inner tent/bug screen with bathtub flooring, with a rainfly that I can also use over the hammock.

I'm not sure how well pitching a hammock with a ground tarp would work in windy conditions.

I've heard that the mosquitoes up there in AK can be vicious, though. That's really what I was thinking of when I suggested using it as a bug bivy.

If you're going to use both, why not simply use a groundsheet with a tarp? That's what folks the world over have been doing with tarptenting for decades now; the only difference would be the use of the hammock as the bug protection rather than a dedicated bug bivy. It'd save you probably an half-pound or so of fabric--not sure how far you intend on going in a day, or in what conditions, so that might be worth it and then again it might not.

In windy conditions, it wouldn't be any harder to set up an hammock as a bivy than it would be to set the tarp up initially. Which is going to be the issue, really; staking down that tarp nice and tight before trying to set the bivy up inside (be it an hammock or a dedicated bivy). At least, that seems the proper order to me. (Please note: I've never used a bivy/tarp combo in windy conditions. I've tested it with my hammock in my back yard, just to be sure that I could, but I've never had to use it under field conditions.)