It is always a bummer to hear about all of the condensation some folks get. I am among that group that has not suffered noticeable condensation with my very limited pad use. Limited, that is, except for the HH Super Shelter(HHSS) with it's open cell foam(aka sponge) pad underneath a space blanket(which is a vapor barrier- VB), which has yet another VB- the sil-nylon under cover- on the outside of both pad and space blanket.
Now this(HHSS) I have used a whole bunch over the years- even set my personal best using it(a mere +6F, us poor southern boys don't get hardly any below zero action). I have never been anything other than bone dry, or worst case a few drops of moisture gathered at the low point of the space blanket. I don't know how many, but I know there are a few other folks here- maybe 1/2 dozen or maybe more- that have had the same experience. In addition, Ducttape and 509 something or other have reported way below zero hangs with no condensation problems, using pads only. However, one of the times that I failed to use the inside VB/space blanket, when I woke up I found my synthetic bag and the HH OCF pad were quite soaked with condensation in the foot area(though still warm, didn't even notice until exiting the hammock). So you see, it is possible for me- like every one else- to get condensation under the right circumstances. Also, on at least one cold weather trip where not one drop of rain or snow ever contacted the shell of my bag, when I got home and measured my 7.5" loft bag(top + bottom layers) was down to less than 6". That was from condensation in the bag.
So the question is: why the difference in the amount of condensation people report? I don't really know, except to say it is tricky business. But here is one factor that plays a part, though I am sure there are others: law of physics = condensation(not to be confused with sweat) occurs on cold surfaces. No one ever sees their breath condense in the air or on their car windshield on a warm day, never. So this may be a clue. When I use the space blanket/VB in the HHSS, it is on the warm side of all of the insulation(OCF pad + whatever unused clothing I might add). So it is kept pretty warm compared to the outside VB that is the under cover. In addition to the fact that I never get any noticeable amount of condensation, it stops any body vapor from making it's way into the cold undercover and condensing there. Bet result: all is dry for me.
I don't know how thick your pad is. (Actually, I do: isn't an auto wind shield pad very thin, with very little insulation/R-value? Isn't it mostly just a VB or space blanket like?) But anything you can do to keep the inner surface of the pad warmer might reduce your condensation. Like a VB hung on the other side of the hammock, to block wind and warm things up a smidgen. Especially if a jacket was placed between that outside VB( sil-nylon, or a space blanket) and the pad. Maybe. Or, maybe if a thicker pad is used? ducttape and 509 have not reported problems, no doubt with thicker pads. I didn't have any at a bit below 20F using a 1" thick Thermarest self inflator on top of a CCF 5/8". (but some one is currently reporting problems with a pad in their Amok hammock, and that is probably a thick pad, so..... )
And don't forget: down quilt users do not escape condensation. They just don't notice it as quickly because it is soaked up in the down. If the trip is short, or they have lots of over fill to help soak it up, or if there is adequate sunshine for drying, they likely won't notice. But I'll bet you if folks weighed their quilts or measured loft, even after a week end trip(depending on temps of course), unless they are using VB clothing or liner, they would realize they had condensation inside their quilts. And if they were out a few more days without sunshine, and packing up every morning, they would have issues. If it is cold enough for the dew point to be even 1/4" inside your outer shell, down or synthetic, you are going to have condensation, guaranteed. You might not notice it for a few days, especially if your quilt is rated 10 or 20 degrees warmer than the coldest temp you encounter, but it will be there. Unless there is adequate sunshine for drying. But I won't get any, thanks to my VB clothing.
Good luck on solving your condensation problem!
Bookmarks