Hey folks,
I am experiencing a problem that seems to be mounting worse and worse as the season gets colder here. Hopefully someone here can tell me exactly what is happening and what I need to do to correct it.
I am using my new high peak simex panda hammock. Which for those that have not read that thread is basically a hammock with sleeping bag permanently attached. The outer shell of the panda is a DWR coated ripstop nylon. Outside of this is another layer of DWR nylon that runs full length and serves as a pad pocket. The insulation for the hammock is synthetic and is inside the hammock. (Yes you compress it when you lay on it).
Inside the hammock I am using 2 parts of the US ARMY standard issue Gortex version partrol bag. (3 piece bivy/bag combo) - I got from Take-a-knee. Against the inner shell fabric of the panda hammock I am using the waterproof synthetic bag from that set. Inside of that I am using the black inner bag which is breathable. This will simulate a cut-away cross section view of how my layers are stacked:
P = pad pocket sleeve on panda hammock (DWR coated ripstop - not insulated, not using any pads)
X = panda hammock bag (synthetic insulation .... this is the problem layer getting soaked on bottom only)
0 = army outer bag (DWR coated ripstop synthetic insulated)
U = army inner bag (breathable nylon, synthetic insulated)
XXXXXXXXXXXXXXXXXXX
X 000000000000000 X
X 0UUUUUUUUUUUUU0 X
X 0UUUUUUUUUUUUU0 X
X 000000000000000 X
XXXXXXXXXXXXXXXXXXX <--------- This is the problem layer right now
PPPPPPPPPPPPPPPPPPP
Here is the problem. When I wake up in the morning, I am getting major!! condensation between the insulation layer of the panda hammock and the outer layer of the DWR army outer bag. I honestly thought someone was playing a joke on me. It was as if someone dumped a large container of water into the hammock. It was in two places. A large circle 20" dia that was roughly from my hips to my shoulders, then a bare dry patch, and a smaller aprox 10 dia circle about where my feet were.
Using the above diagram will help explain better. Layer PPPPPPPP is bone dry. One layer up from that XXXXXXXXXXXXX is absolutely soaking wet by morning. I would estimate a pint of water or more this morning, drenching the bag. One layer up the bottom layer 00000000000000 stayed dry because it was DWR ripstop. I am not currently using any CCF pads in the pad pocket of the hammock.
I am trying to establish how low I can get this setup before I have to add pads to the bottom insulation, and better calculate how much warmth one layer of 3/8" CCF will add.
here were my weather conditions for last night:
-2 deg C, 50km/h wind, 80% humidity. Light rain/freezing rain during day.
One hour rain storm at aprox 11pm. No precip beyond midnight.
Worth mentioning. I did not sweat at all during the night. I was at perfect sleeping comfort, breathing outside of bag, and aprox 1/4 unzipped for ventilation. In past weekends I noticed this moisture, but chalked it up to my own sweat, and overheating myself in
the night. I know now for sure this is not the case.
So ..... what is causing my serious condensation issue?
How am I getting that first bottom layer of insulation so thoroughly soaking
wet, and yet no visible signs of moisture anywhere else. I think it has something to do with the pad pocket and the fact that I am not using a pad in it. Can anyone explain to me what is happening ?
I would have thought that the inside of the pad sleeve would have been wet. And I certainly expected the DWR nylon on the outer shell of the US army outer bag to be slick with moisture, yet it was completely dry. But somehow my bottom and first insulation layer which is the hammock layer is getting wetter and wetter as night time temps drop, and I add layers to my system.
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