Interesting HH BULA Observation

[Just Jeff]

I set up my HH in the backyard two days ago with the KAQ under it. Then I went for a walk, and while I was gone the dewpoint came around...everything got wet. Not soaked, but still wet. So I left it up and let it dry yesterday.

When I went back out to check it, everything was dry...except a puddle of water in the hammock body. The underquilt underneath the puddle was completely dry, but the hammock was holding a puddle of water!

I know the fabric is breathable, and I'm pretty sure it's not waterproof when it stretches, but I was surprised to see this. Probably wouldn't be of any use to underquilt users since the water would likely come in from outside when in the field, but for pad users it might be a little bit of added protection from windblown rain.

[Youngblood]

Jeff,

I'm not quite sure I'm following everything you're saying. First of all what does BULA mean and second, did you have a tarp over your hammock?

Waterproof and breathable are both relative terms, there are degrees of waterproofness and degrees of breathablity. For instance, in a light misting rain a jacket with a good Durable Water Resistant (DWR) will be waterproof as long as a certain pressure isn't exceeded on its surface. Likewise, even the bugnetting on your HH can act like a vapor barrier as long as a certain differential pressure isn't exceeded on its surface. Air or vapor has to be forced through it, in a light breeze you might not even feel the air moving.

Condensation issues are complex. You can get condensation in a hammock setup from high humidity air cooling to it's dew point, which introduces mositure from the top. You can get condensation from humidity rising from dry ground, which introduces mositure from the bottom. You can get condensation from being in a fog bank which just gets things wet from all over. You can also get condensation from respiration, insensible perspiration and perspiration (sweating) which introduces moisture from the inside of your hammock system.

[Just Jeff]

BULA is Backpacker UltraLite Asym.

No tarp, and I wasn't in the hammock so it wasn't condensation from me.

I wasn't aware that this material had ANY type of DWR on it - maybe it's just such a tight weave. Regardless, it had a puddle of water in the bottom when I walked up to it.

[Youngblood]

That's amazing isn't it... an empty hammock collecting a pool of water because of dew.

I've seen small amounts of water pool in the bottom of my empty hammock when I was testing webbing for water running down it. The hammock was 1.9 oz rip stop nylon with DWR (and maybe calendered). I think it slowly wicked out and dried in an hour or so, but that was an open top hammock without a bugnet in warm weather. What I think happened was that the water wicked from the end knots with the help of gravity to the center of the hammock and somehow pooled on the inside of the hammock. Water can do some weird stuff.