Anyone sleep in a Bivy? (US Military Gore Tex Bivy vs. MSR E-Bivy)

Macchina

Macchina

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Hello,
I am looking into ditching the tent this summer, and I think I'm going go the route of the Bivy. No matter which I get, I will sleeping in a Snugpak Softie 9 with a tarp and/or a Thermarest Prolite 3 pad underneath me. I expect temps to get down to around 40 on some of the hikes, but may stay up near 80 on one hike this summer (in which case I'll be using my 50 degree Lafuma bag and sleep out of the bivy unless it rains).

I'm looking for opinions on these two options or any other options under $100:

US Military Gore Tex Bivy: Somewhat heavy and bulky at 2lbs., but 100% waterproof. It is made of Gore Tex and very durable as far I can tell. I think I'd like to go with this one if I knew how it performed in a downpour: will I suffocate with my head sealed inside, how is the condensation? No stuff sack included. Made in the USA!

MSR E-Bivy: Lightweight and compact (which is the only winning factor of this one over the one listed above) and also 100% waterproof. Made of coated silnylon on top which has a strong following in the ultralight circles. From what I've read it performs well when fully closed up with the expected condensation that comes with breathing into a waterproof bag (I have no hopes of no condensation). Comes with a stuff sack. Made in Taiwan.
 
i use to use the army bivy on a regular. it was awesome compared to the options before. hell we would be out doing our thing set up a patrol base and no matter the weather you were good. just pull out the bivy and small bag get in and your good to go.

if you had all 3 bags with you which in germany for training we very often did lol, we use to take our wet clothes off and put them in between the green and black bag and and the gortex on the outside and you slept on them. and for the most part when you woke up the next day your bdu's were pretty dry. smelled a bit musty but still better than running around in soaking wet clothes

never used the other one but i still have my military set up to this day and i love it. you dont have to set up a tarp or anything just get in it pull the flap over you head and sleep lol
 
Thanks for the response. I am leaning towards the military bivy for many reasons. What's it like sleeping all closed up? I am not clusterphobic at all, I'm mainly wondering about getting enough air or if you get soaked by your breath?
 
Look into Eagles nest hammocks as well, just a hammock and a bug net, although you can build your system over time. You probably already have a suitable tarp, and you can use a hammock on the ground if you wish or have to. There are better hammocks, but these give you a lot of bang for the buck. Think of it as a hangable bivy.
 
With a hammock, you NEED a tarp for water proofing (or a cocoon type hammock which is heavier than a lot of solo tents). I thought about going that route, but they are all so expensive and for that price I'd rather invest in a lightweight 2-man tent for the the times my wife goes hiking with me...
 
The GI Bivy is really nice. It's durable, waterproof, if you maintain the coating.

IMO sleeping with the bivy covering your head isn't a good idea with any bivy. Not just because of breath condensation (it will), but I find myself breathing too much CO2 in an enclosed space. You're better off stringing up a tarp or poncho above your head.
 
michaelmcgo said:
Thanks for the response. I am leaning towards the military bivy for many reasons. What's it like sleeping all closed up? I am not clusterphobic at all, I'm mainly wondering about getting enough air or if you get soaked by your breath?
Click to expand...

The USGI sleep system is a mummy bag. There is nothing covering up your face, etc. The system layers nicely, and I never actually had to use both the green and black bag combined. There is a pretty big step up between the heavy black and lighter green bags. The goretex cover is great. Great system, I should buy one. Bulky, but the stuff sack can compact it into the size of a basketball.
 
I've lived in bivy's for months at a time as a mountain guide and for days at a time in the military, so I can give you some insight from those points of view.

Bivy's are usually all waterproof breathable (WPB) like Gore-tex, eVent, Pertex Quantum, EPIC by Nextec, etc. or a hybrid with a WPB top and waterproof non-breathable bottom. Avoid bivy's that are made from all non-breathable materials, as they have all of the problems with few of the benefits. An all WPB bag will ALWAYS have less condensation than the hybrids, no matter what anyone claims. The idea of the hybrid is that you're sleeping on the bottom so it's not going to breathe and the WPBs are really not 100% waterproof (especially when dirty, which the bottom of the bivy will get) so why not save money and use a 100% waterproof bottom and have more waterproofness to boot? This is fine, but they will have more condensation, especially in the temps you're looking at using it (down to the 40's). I prefer to use bivy sacks in sub-freezing temps, which helps to reduce condensation. I also prefer 100% WPB bivies, as I tend to sweat heavy so there's always more condensation with me. !00% WPB bivies are going to be more expensive, and can be heavier than the ultralight models that use silnylon or other such materials on the bottom.

I also prefer to use the most breathable materials possible. Of course when I used them for long lengths of time it was at altitude where it's dry and I didn't have to worry about rain, so ymmv. My preferred materials are eVent, Gore Dryloft and EPIC. Of those materials, only the eVent is fully waterproof, and it's very expensive, but it breathes much much better than Gore-tex (although I haven't used Gore's air-permeable material that is used in some bivies).

You also need to consider if you want one with a hoop, wire, etc. over the face area to keep it off of you, which goes a long long way towards helping you to feel less clausterphobic. I definitely prefer a wire or hoop and no-see-um mesh to keep the bugs away, but this increases weight and cost.

Never sleep in a bivy fully closed (although I heard that the Gore air-permeable material is supposed to make this possible, but don't quote me)! This kills climbers every year and I've lost several friends and colleagues this way. When it's 50 or 60 degrees below 0 it's very tempting to zip up that bag to try to preserve warmth, especially if you're calorically deficient, oxygen starved and exhausted.

I have several bivies, including the military Gore-tex model I was issued. It's actually not a bad model, but it's heavy and bulky, but at least it's all Gore-tex. The seams leak like crazy, but seam sealer takes care of that.

There are great models made by Integral Designs, MontBell, Outdoor Research, MSR, Bibler and Black Diamond, Backpackinglight.com, Oware, and by Big Agnes now.
 
That is exactly what I was wondering. I thought it might have a mesh area or something...
 
I have been using bivy's (among other methods) for many years.

The best I have come across are made by Bibler.
They also make the bivy's for Black Diamond.

I have two made by Black Diamond/Bibler, and they are different, but both top notch.

They are tops for these main reasons:
-inner wicking liner keeps the condensation to a zero. This is a big problem with bivy's.
-bug nets to sleep looking at the stars.
-Sturdy footprint bottom so no additional footprint is needed.
-Extremely lightweight.
-Sturdy seams and zippers.
-Super thick material.
-means of keeping the bivy from your face.

One is a typical Bivy. I used only this for hiking The Sottish Highlands.
Weighs nothing and rolls up small & tight.
The seams are completely sealed.
Copper wire inside allows you to bend the bug net/entry area and hoop it so it doesn't fall on your face, letting the bugs just bite away.

The second is a bivy-tent.
Basically a bivy with two small poles that make for a little hoop about the head.
Three stakes. Also weighs nothing.
Inner pockets and room about the head for minimal storage.

Bivy's have come a long way as of late, esp. with the advent of the bivy-tent and wicking liners....

I don't use them exclusively, but if I were to guide someone up a mountian or through a valley in short time with long hours of hiking and little time for camp prep, I'd grab one.

Coming from an Alaskan mountaineering/outdoors family, I always appreciated bivy's for their ease and weight. Mostly for quick rest and then move on.

However, I find them a bit of a nuisance if the intent is to relax. Or have an extended base camp/kitchen...
Getting in and out of them and keeping them clean.
Bivy-tents allow for much more of this... I'd look into them if this is a consideration. I do love mine and I've put it through some hearty paces.

Choosing a spot with minimal sun exposure is also to be considered as they can very quickly become ovens.
 
Kage and Paleojoe offered-up some great advice.

Bivy sacs are awesome in that they're sooo light, but consider why you want a bivy. Mountaineers use them b/c there often isn't enough space for a tent. Bivy sacs are not the most comfortable "shelter" especially in inclement weather. Also, if you're hiking with mates, you don't have a "social space" ... bring a tarp along and you might as well have a tent. Reading a book, getting changed etc etc [in bad weather] is also difficult. Unlike you, I am claustrophobic, so I usually consider bivy sacs as a necessary evil when climbing. There are lots of really lightweight tents out there which perform better in hot conditions [and are more comfortable - generally]. I'm not saying "buy a tent", but just consider why you want a bivy sac. Additionally, I would imagine a Gore-Tex bivy would be miserable in 80 deg heat.

All that said, I have a Bibler Big Wall Bivy and it's a great design. I've used it in teeming rain on glaciers with the vent about 75% open and have been perfectly dry. It's more than $100, but consider used if you can find one. Another option would be a Bibler Tripod Bivy - a tent/bivy hybrid. Again, more expensive than $100, but used it should be close to your budget. Both use a proprietary breathable fabric. For those who don't know Bibler [now owned by Black Diamond Equipment], their tents/bivy sacs are legendary in the climbing/mountaineering world.

Considering summer use only and light rains, a bivy made of EPIC might be nice as it's highly breathable, tough, and offers just enough protection against rain. Cost effective too.
 
I just bought one of the U.S. Bivy's at a thrift store for $2 three days ago and fell in love. I liked it so much I bought one on "that auction site" yesterday for $40 brand NEW. One for me and one for my girlfriend. For the price, you cannot beat it. Maybe one day I'll spend hundreds for a nicer one. For now, I can carry the extra ounces with glee.
 
My first is a US Marine Corp bivi and I still have it. It works but it is big and heavy. Takes up way too much room. So I switched to the Intergral Designs eVent Crysallis with no regrets whatsoever. The ID Crysallis is considerably lighter, breaths a 1000% better, allows me to use the micro netting in warmer weather and can be zipped up tight for a rough night.

I apprecate the ability to open the high vent to let moisture and air out at night.

I still have the Mil Bivi and it is a loaner for guests.
 
For the last few years, I've been sleeping in a bivy about 100-200 days per year. I like how small they are, how light they are, how fast and easy they are, with basically nothing to set up.

My favorites are the Bibler bivies – for several reasons, but primarily because the have a slightly fuzzy, napped interior, which absorbs condensation, and helps transport it to the outside of the waterproof/breathable material, much more efficiently. Unfortunately, they are outside of your price range. However, if you can find a bivy with a slightly fuzzy interior, within your price range, it's with considering. They are far superior.

Even if the weather is threatening, I generally don't pull the bivy up all the way over me, and zip up, unless precipitation is coming down, or unless I need to, for warmth.

I still have some very nice tents, but I hardly ever use them, anymore. I prefer bivies. Also, I don't recommend the bivies with poles, hoops, etc. They start to approach the weight, size, time to set up, and expense of a tent, but still are not really much roomier in the head area. I do like bivvies with a bendable wire, to keep the fabric off my face.
 
Evolute said:
Also, I don't recommend the bivies with poles, hoops, etc. They start to approach the weight, size, time to set up, and expense of a tent, but still are not really much roomier in the head area.
Click to expand...

I once thought that, but after owning both bivvies and bivy-tents for years, I can vouch for them.

My Black Diamond/Bibler bivy-tent is not much heavier at all.
And is very still small to pack.
The head space provided is way more than any bivy I've tried. I can read in it, store another pack inside, put things in the inner pockets, sit up, and dry clothes on the dome.
The mosquito net is well above head which allows for nice star views.
The pole is very small and it takes very little extra time to setup.

The bendable wires in regular bivvies are only somewhat functional. They don't do the best of a job IMO...

A bivy-tent allows for a step up in comfort, and longer camp setups vs. a regular bivy. Getting in and out is easier. Also a step up if snow or rain is a concern. The trade up is so little in terms of weight and size for what you get. Very minimal, we're talking 2 lbs 10 oz vs. 1 lb 12 oz (the Tarptent ultralight contrail weighs 1.53 lbs. without poles)

I'm a fan of both, but there is a time and place for each, in my experience.
I've tried several times to pick one, just one between the two, and I couldn't do it.

As for the price, I got mine used/returned for half the cost at a local outdoors store.
There are some things I believe in spending on for the amount of quality you receive, I think these sorts of equipment fit that category.
Then again, the use may differ for everyone.
 
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I absolutely love my bivy bag. Swear by it. One of the better investments. So much better than a tent.

Get one of the ones with an open face and string a tarp if it rains... much better option than sleeping all closed up.
 
I've got a Bibler Tripod too (scored it from Black Diamond before it was released), and it has its place in my stable of bivies. It's not a lot lighter than my ultralight tents, but it'll go places my ultralight tents won't go (only a few ounces lighter than my Black Diamond Beta Light, which has considerably more room, but uses trekking poles instead of dedicated poles, which is part of the weight savings). I was climbing in the Northern Japanese Alps when I taiphoon blew through and my Tripod was one of the only standing shelters left at base camp. I rode it out in relative comfort and then helped everyone else to patch poles, find rain flies, etc. I estimate winds probably hit 120+mph for a very short time and sent several tents flying off the mountain. The other thing is that it allows a lot more room for extended stays, vs. my Bibler Big Wall Bivy, and as a mountain guide it allowed me privacy because there's no room for anyone else, which means no sharing a coffin sized 2-man mountaineering tent.

I do wish that Black Diamond had made the EPIC version when I bought the Tripod, as it's lighter, simpler and more breathable.

The beauty of bivies for climbers is that they take up very little real estate, and you can chop a smaller ledge for a bivy sack than a tent. They're also lighter, more compact and small enough you can use it for emergency shelter during a summit bid (I've owned several Montbell Dryloft bivy sacks that weighed around 7 oz. but are basically disposable).

For backpackers, it's weight savings and space in the ultralight pack. If I were just backpacking I would rather use a TarpTent or something similar, which are amazingly lightweight but allow much more room, less condensation when you learn how to compensate for it, full mosquito protection, and room for social calls.

Just food for thought...bivies are not for everyone.
 
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well said kage!

I hear you on the EPIC...
Those Tripods are hearty though! Built for all-weather conditions...

I do love the weight and comfort of those Tarptents. Much more air inside, better for my hot summer climate!
And yes, those social calls!
 
After a lot of searching for a bivy that is inexpensive but has head room, I decided that if you are on a budget: a bivy is not for you! I'm am amazed at the $250 cost of most of these things. Paying for research is one thing, but wallet rape is another!

I think I'm going to go the ultralight tent route. The bivy was going to replace my Eureka Apex 3 tent (I usually carry it and share it with somebody who is carrying the pot/filter/stove). I think I'm going to go with this.
 
Hey Joe! You'd be surprised by how tough BD's EPIC tents are. I've been in the Lighthouse for days of insanely bad driving snow, hoar frost, frozen rain, etc. and it breezed through without a scratch. I was seriously regretting not having a Bibler or Integral Designs, or even better one of my heavy but indestructable Moss tents, and I was seriously thinking the EPIC was going to shred and was starting to fear for our safety, but the BD just laughed back, and all without any condensation. I don't own an EPIC tent, but if I was still guiding I would.

If you want a basic, no-frills bivy Black Diamond's Winter Bivy fits the bill. It doesn't offer mosquito protection or even close up tight, but it's light, breathable (made of EPIC), and cheap (less than $100). For me it's perfect for snow caves, to waterproof an ultralight down bag. It is NOT 100% waterproof! Do wish it came in a bright color, but it only comes in black.
 
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