Bivy Bag Questions

[daddymac]

So I like the theory, but just how good are bivy bags? I am considering a bivy bag for lightweight solo camping instead of a tent. My concerns are staying dry and not baking in the thing. Do you get much condensation? Material suggestions?

Thanks for your input,
j

 

[skammer]

They get very hot in summer. For winter and or fall spring they work well.

For summer I use a silnylon tarp and bug net for a breeze.

Make sure its made out of the best breathable gortex type.

Condensation does build up depending on temps out.

It is a good pice of kit though just realize its not for the heat of the summer.

Skam

 

[Erasmus]

I got the Outdoor Research Standard bivy. 7 years ago, they were the best one (for me), @ $200. Now, who knows. Search over at rei.com and see what is current.

Mine has been great for high altitudes in the Sierra Nevadas, in Summer.

 

[mckrob]

They get very hot in summer. For winter and or fall spring they work well.

For summer I use a silnylon tarp and bug net for a breeze.

Make sure its made out of the best breathable gortex type.

Condensation does build up depending on temps out.

It is a good pice of kit though just realize its not for the heat of the summer.

Skam

Well said.

I have a high quality goretex bivy (for 10-12 years now) and quite like it, in hindsite though I would have got one with a hoop to give a bit of head-room, if I am forced to zip up the bug net in the summer when the mosquitos are thick, the net eventually ends up on may face and the bugs will try to bite through waking me up constantly. A hooped model would raise the net up enough to avoid this problem.

I use my bivy sack mostly in the winter when sleeping in quonsets or igloos, my MEC goretex bivy is super waterproof and breathable, but I daily (weather permitting) hang the bivy with my bag inside in the sun to dry out.

In the summer it is very hot and I will use it with only my cotton sleeping bag liner (basically a bed sheet with a zipper).

 

[bikerider]

I have used the REI minimalist bivy on the channel islands in summer and the Sierra's in the fall. It did not develop much in the way of condensation. I've had worse condensation problems in some tents I use it in conjunction with a sil tarp if I'm going for more than an overnighter. It is big enough to put a therma rest inside, so you can't roll off it. Wait for a sale and you can pick them up for $60.

 

[Evolute]

I use a bivy bag often.

The secret to avoiding condensation is getting a bivy with a thin fuzzy lining laminated to the waterproof/breathable material, to help disperse the moisture more effectively, and help wick the moisture to the outside of the material, instead of one with smooth gore tex on the inside, where the moisture collects in beads that run down to the bottom and form a puddle.

 

[kr1]

They get very hot in summer. For winter and or fall spring they work well.

For summer I use a silnylon tarp and bug net for a breeze.

Make sure its made out of the best breathable gortex type.

Condensation does build up depending on temps out.

It is a good pice of kit though just realize its not for the heat of the summer.

Skam

Get hot my arse. You could melt lead inside that thing. I had the OR loop bivy when they came out several years ago and it tried to kill me more than once. In the summer if you have to batten it down because of heavy rain it will immediately go to 130 degrees or so inside. In the winter you must run it open at least a little or you will get sick/(die?) from carbon dioxide poisoning. I had the opening in the winter close twice from a heavy wet snowfall and awoke with such a headache. Hell, I was glad I woke at all. The only thing the piece of crap needs is handles and it would be a perfect body bag.

I got rid of mine a long time ago. Using a tarp or other options are much better.

Just one persons opinion.

YMMV,
KR

 

[Pritch]

I have a high quality goretex bivy (for 10-12 years now) and quite like it, in hindsite though I would have got one with a hoop to give a bit of head-room, if I am forced to zip up the bug net in the summer when the mosquitos are thick, the net eventually ends up on may face and the bugs will try to bite through waking me up constantly. A hooped model would raise the net up enough to avoid this problem.

mckrob, I recently read something by an ultralight hiker that had an interesting solution to keep the screen off her face without having to pack a heavy hoop. She carried a few of those baloons that clowns/mimes/Canadians use to make baloon animals. She would inflate one into a long hoop and it was sufficient to hold the screen or bivy off of her and weighed almost nothing. Apparently this is a one-time use kind of an item.

-- FLIX

 

[jarlaxle]

they are probably just as bad in summer as winter. In cold weather camping you want something that will let moisture escape. 1 person will will breath out about 1 pint of water a night, when that moisture cant escape it will freeze and make the internal temp drop.

 

[Evolute]

mckrob,

my bivy has a loop of fabric running across, just above the shoulders for a replaceable piece of light gauge copper wire. The wire serves as a hoop to keep the fabric off your face, without the size, weight, and cost penalties of a hoop. It weighs nothing, crumples down into nothing, and is replaceable easily and for dirt cheap. Perhaps you can make a wire work in yours.

 

[mckrob]

Truthfully, the netting in the face/mosquito issue has only been a problem for one trip on one night, if I have some time I will see if I can't rig something up, maybe just a couple of sewn on pockets on the inside left and right of my head to accomodate a bent twig to raise the netting. The baloon thing sounds interesting

99% of the time I have used the bivy sack it has been when there have been no bugs (fall and winter camping) when I can leave the zipper open and myself well ventilated. I have slept in dry comfort in pouring rain with it done up, again this was late fall and around +5C, there was a fair bit of moisture inside, but not enough to seriously affect the sleeping bag's performance, although it would be an issue with sustained days of rain and no daytime sun to dry the bag.

Sleeping in a quonset, even at -35C outside, it can get quite wet inside, a couple of candles will quite easily keep a properly constructed quonset above freezing, there will be lots of dripping from the melting snow on the ceiling, the goretex does a great job of keeping this off your sleeping bag.

 

[Sound Idea]

Truthfully, the netting in the face/mosquito issue has only been a problem for one trip on one night, if I have some time I will see if I can't rig something up, maybe just a couple of sewn on pockets on the inside left and right of my head to accomodate a bent twig to raise the netting. The baloon thing sounds interesting

Wear a ball-cap while you sleep, the bill keeps the net off your face. Cheep and cheerful, and a rolled-up cap can double as a sunglasses-case if you don't like wearing one during the day.

 

[runningboar]

The only bivy bag I have any experience with is the current issue USGI goretex bivy and I really like it. It has kept me warm and dry in some pretty bad weather, however, I would never rely on it alone. I will always have a tarp or at the very least my poncho, being zipped up in a bivy in 90 degree rainy weather would be torture. Chris

 

[Bumppo]

They can be difficult to pee in, in the middle of the rainy, cold, windy night. Just a consideration to ponder.

 

[desmobob]

I spent some dough on an Integral Designs Salathe bivy. It rarely gets used. I do carry it as an emergency shelter though.

They seem like a great idea for saving weight on a backpacking trip, but the lack of convenience makes them less desirable than a good solo tent to me (I have a Big Agnes Seedhouse 1 solo tent that I think is just about perfect).

Stay sharp,
desmobob

 

[kgd]

How about these hammocks?
Hennessy Expedition Hammock - 1.2 kg total wt (a lighter version availble for 0.8 kg). You don't require a sleeping pad saving you additional weight over a bivy. As long as you can find 2 trees 20' apart you are in good shape. The suspended tarp will keep those bugs away and help with ventillation.

I don't own one but have been seriously thinking about it. Here is a review:

http://outdoors-magazine.com/s_article.php?id_article=170

 

[beef]

you still need to use a sleeping pad or underquilt. The bottom of your sleeping bag gets compressed under you and provides very little insulation.

 

[kgd]

you still need to use a sleeping pad or underquilt. The bottom of your sleeping bag gets compressed under you and provides very little insulation.

You are correct. Here is what it says in the MEC catalogue (who I find unlike other sellers usually give respectable advice based on member experience).

Since the hammock holds you above the cold, hard ground, in warmer weather you need only a thin sleeping pad (if any) for insulation and cushioning – thus potentially saving even more weight and space in your pack.

 

[Rich_S]

I have an Integral Designs South Col bivy. I like it. I still use a tarp over it, particularly if expecting rain.

 

[ilbruche]

I use a bivy bag often.

The secret to avoiding condensation is getting a bivy with a thin fuzzy lining laminated to the waterproof/breathable material, to help disperse the moisture more effectively, and help wick the moisture to the outside of the material, instead of one with smooth gore tex on the inside, where the moisture collects in beads that run down to the bottom and form a puddle.

I have the Integral designs Unishelter XP. It has the same fabric. It is way better than gore-tex which is the most over hyped material on the planet.

In summer I have a light one man tent if I have to worry about bugs. If no bugs I go with a 5' X 8' silnylon tarp that weighs 7 ounces.

The bivy isn't really designed for summer use or regular backpacking. The strength of the bivy is its waterproofness and its ability to fit in small spaces. If your climbing mountains in winter a bivy is ideal. For summer use there is no way I'd bring my bivy.