Raining in the Bivy Sack

1SevenZero

Well-Known Member
Joined
Jul 28, 2012
Messages
56
Had to weather a night of heavy rain in my bivy sack the other day. It kept the rain out, but the condensation inside from breathing was enough to make the whole hood of my sleeping bag damp.

What are ya'll doing to combat this?

I was thinking about bringing a small shammy next time and just mopping the hood area throughout the night.
 
If I had to use a bivy it would be something like a integral designs nester, its made of event and breaths very well. You can run it with only the top hoop to lighten it up, But if Im going solo I run a copper spur UL1 at only 2lbs 6 oz its hard to beat. The only down side compared to a bivy is it takes up more room in the pack.
 
If I had to use a bivy it would be something like a integral designs nester, its made of event and breaths very well. You can run it with only the top hoop to lighten it up, But if Im going solo I run a copper spur UL1 at only 2lbs 6 oz its hard to beat. The only down side compared to a bivy is it takes up more room in the pack.

I use the Fly Creek UL1 here in very wet Oregon when solo. It does a great job of keeping the condensation and rain off....and very light too.
 
dont where cloths in the bag strip down to your draws or less

...BVD's

+10. The more you have on (with the fly zipped) the wetter you get. I sleep in a bivy all the time in the summer when I motorcycle camp on my ADV bike. It's paramount to sleep as close to naked as you can get, the more layers of clothing, the more moisture you give off that collects in the inside of the bivy sack.

I always try to sleep with the fly opened up and if no bad weather, the fly off entirely.

By design, they all sweat a little. You perspire and the bivy material is cooler so it condenses.
 
...BVD's

+10. The more you have on (with the fly zipped) the wetter you get. I sleep in a bivy all the time in the summer when I motorcycle camp on my ADV bike. It's paramount to sleep as close to naked as you can get, the more layers of clothing, the more moisture you give off that collects in the inside of the bivy sack.

I always try to sleep with the fly opened up and if no bad weather, the fly off entirely.

By design, they all sweat a little. You perspire and the bivy material is cooler so it condenses.

Very first thing they teach at cold weather survival training
 
...BVD's

+10. The more you have on (with the fly zipped) the wetter you get. I sleep in a bivy all the time in the summer when I motorcycle camp on my ADV bike. It's paramount to sleep as close to naked as you can get, the more layers of clothing, the more moisture you give off that collects in the inside of the bivy sack.

I always try to sleep with the fly opened up and if no bad weather, the fly off entirely.

By design, they all sweat a little. You perspire and the bivy material is cooler so it condenses.

This seems backwards to me, but I'll give it a try. To me it seems like the more layers you have on (within reason) the less perspiration would make it to the bivy cover.
 
Keep your face ,especially your moth and nose out of the sack. If it is too cold to leave your face exposed, wrap your head with a wool scarf.
 
The more you have on (with the fly zipped) the wetter you get. I sleep in a bivy all the time in the summer when I motorcycle camp on my ADV bike. It's paramount to sleep as close to naked as you can get, the more layers of clothing, the more moisture you give off that collects in the inside of the bivy sack.

I always try to sleep with the fly opened up and if no bad weather, the fly off entirely.

First time poster and new to LRH, but I thought I'd comment here. Haven't had cold weather survival training, but have slept a lot in the snow and cold. I don't get the above. While I do try to sleep with as little as possible, for me this is a function of temperature and gear. Traveling light, when it's cold (below freezing), I am wearing everything that I brought when I go to bed. Of course, if you're roasting in a winter bag with all your clothes on, it's too much, but a three-season bag works pretty well in the winter if you have the right clothes on (and is lighter in the end).

Maybe the point is to wear as little as you need in order to not overheat while you sleep.

2KYDS
 
Had to weather a night of heavy rain in my bivy sack the other day. It kept the rain out, but the condensation inside from breathing was enough to make the whole hood of my sleeping bag damp.

What are ya'll doing to combat this?

I was thinking about bringing a small shammy next time and just mopping the hood area throughout the night.

I don't see any good way around this happening, depending upon the design of the bivy. A larger hood can channel the condensation around you but then you have a tent. Being wet in cold weather won't fly. I think that I'd take a small tarp and some cord and make a roof over the bivy and sleep with my head outside. I hunted the Oregon/Washington coast once and almost all the camps that I saw had a tarp rigged over their tents. After enduring the wet, cold conditions and putting on frozen clothes every morning, I saw why they went to the extra effort.
 
I've come to the conclusion I'm going to set up a light tarp like a small tent. This way I can keep my hood atleast partially unzipped.
 
I've come to the conclusion I'm going to set up a light tarp like a small tent. This way I can keep my hood atleast partially unzipped.

Yeah, that will help. How damp is your hood of your bag? On multiday trips with wet weather I've had my bag get progressively wetter. It's somewhat unpleasant, but if it's not too cold and you have a synthetic bag it's not a problem. In cold weather a wet bag could be bad... The flip side is that when it's really cold all the condensation just freezes on the bivy and it's pretty easy to keep the gear dry.

Personally, I'd just deal with the damp bag rather than carry the extra weight of a tarp etc. If you can rig a little hood between some trees that might do the trick. Some bivy sacks have built-in hoods - I don't know if they're meant to stay open in the rain though.

Yeah, there's condensation in the bag when it's zipped tight in a storm, but better than being open to the rain! :)

2KYDS
 
Warning! This thread is more than 11 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top