Bivies…I want to love them…but…

Craig- I think w/ a bag it’s a little less value, with a quilt it just about eliminates draft issues- in addition you get a ground cloth built in (that’s worth and ounce or two in of itself) and if windy (bag or quilt) there is some definitely some value; mine is oversized to accommodate a 2.5″ pad- so it helps keep everything together (including my pillow); if you were lucky enough to get just a minor sprinkle, it would certainly be helpful for that (talking water resistant/breathable bivy here)

as far as boosting sleep system temps, my experience is that it probably does a little (you get an additional boundary of warm air), but not significantly- hard to put a number on it, but maybe 5 degrees

Mike

To be clear, I’ve slept out without a bivy (bag alone) more times than I can count.  Easily over 100, I know that much.  With a bivy (of the lightweight DWR type discussed here), at least two dozen times.  So I’m relatively less experienced with the bivy, but have been out enough.

The worst that’s ever happened to me in a bag is dampness that never quite got bad enough to get through the shell, or dampness that then froze over and never really effected loft.

The worst that’s happened in a bivy is far worse; completely trapped moisture, resulting in really wetting out badly…as experienced on this last trip.  I would’ve been curious to have seen what would’ve happened to a bag alone under those conditions.  I suspect it actually would have been better as the moisture could have frozen, preventing it from soaking in.  As it was, being trapped between the bag and bivy, it never froze, only accumulated and saturated everything.  The inside of the bivy was far wetter than the outside of the bivy, leaving me to believe a bag alone would’ve handled it better.

I definitely agree that the bivy boosts warmth.  But for reference, my bivy weighs 6oz.  That’s nearly the difference between my 35 degree bag and my 20 degree bag (the 20 being good down to 15 IME).  So If it’s a matter of simply boosting warmth, I’m not sure the bivy does much for you that a heavier bag doesn’t.  I have WM bags and have found their shells as wind-proof as any bivy I’ve used.

The aspect I like the most about the bivy is the self-contained nature of the system;pad, groundsheet, and insulation all integrated into a package.  Last hunting season I spent two nights on a ridge tucked between some bushes in a very narrow patch where this seemed to come in handy.  But I could’ve managed with a groundsheet/pad/bag…it just seems the bivy keeps the system a bit “cleaner” both literally and figuratively.  That’s what appeals to me about them.

Maybe for my purposes, a mesh-top bivy would be the answer; it solves the issues with condensation but ties the sleep system together into a nice, clean package for camping in the scrub.

@awhite4777

Curious why you’d consider switching from Hex Solo to Hex Pocket. Just to save a couple of ounces?

I am going with a Hexamid Solo Tarp + S2S Net/Polycro this year for the High Sierra.

FWIW, I recently purchased a Borah DCF bivy but immediately sold it after realizing it would not be a good fit under the Hex Solo, as the tarp wall is too close to my face to be able to suspend the head of the bivy in a manner that it doesn’t just loosely lay over the sides of my face, which I found irritating. The S2S, as you probably know, can be weighted/staked at the corners, allowing a decently taught angle of netting that creates a little more livability. Still, I wouldn’t want to do much more than just sit up briefly under the S2S net, but thats true for the tarp by itself also. I found the side zip bivy to be just as fiddly and annoying to get into and out of as the S2S net, maybe worse even. The S2S+Polycro weighs the same and costs about 1/3 of what a DCF bivy goes for.

Craig- our experience I believe was due to very heavy dew (and quite possibly some condensation added to it).  With the temps as they were, you may have been better without the bivy- less soaking, more freezing- it (the lwt bivy) certainly didn’t help in that situation and possibly added to it

With your use of the bivy described above (not needing it for some additional protection from rain/snow w/ a smaller tent)- a bivy w/ a mesh top, might be the ticket.

Mike

Mike

We might all be on similar pages of the book. in the circumstances most of you are describing I have been using a custom UL Gamut from Nunatak using 7d Robic, but it isn’t a bivvy or sleeping bag cover as it is open on the bottom and I need a groundsheet under the pad. The 7d Robic certainly isn’t waterproof but it does allow quite a bit of vapour transmission and it shakes off dew etc reasonably well

A D said:

Curious why you’d consider switching from Hex Solo to Hex Pocket. Just to save a couple of ounces?

I mention it primarily because ZPacks discontinued the Hexamid with the exception of the pocket version. My Hexamid Solo tarp is six years old, and getting long in the tooth (i.e., small holes in a few spots), but for others considering this route, the pocket tarp is the only Hexamid option.

Also–for short good-weather trips, or long dayhikes/runs, buying a pocket Hexamid would save wear* on my now irreplaceable Hexamid Solo, and save weight and volume in my pack. I would almost certainly not pitch it, but would prefer to have a shelter if surprising conditions occur. To go back to the roots of this thread–the pocket Hexamid would make a great “pitch only when needed to manage condensation” shelter.

I don’t usually suspend my bivy inside my Hexamid–I just wear a baseball cap (sometimes sideways if I’m side sleeping) to elevate the netting/bivy material off my face when zipped up. So maybe a Borah bivy wouldn’t be so bad? But I usually leave the bivy unzipped, unless bugs are about, or I’m looking for the last iota of warmth in my sleep system.

I’ve used the Hexamid + S2S + polycro. Definitely a light option, and I do the same thing–weight or stake the corners of the S2S, and hang the apex from the internal apex loop in the Hexamid. Quite nice! In general, I find the S2S slightly more fiddly than a bivy (due to the paragraph above). In extremely buggy weather (a likely descriptor of much of this summer), the S2S netting has the distinct advantage of being easily pitchable any time you stop for a break. Whereas, I know nobody that wants to climb into a bivy midday during a break. When the skeeters are really swarming, it can be nice to have an easily-pitchable respite. In those cases, regardless of whether or not one brings a bivy, the S2S netting can be a worthwhile addition.

I’m not particularly fond of this approach in severe or extended poor weather–the Hexamid is small, and now you need to manage your netting and your groundsheet, minding wind, splatter, etc.

No free lunches!

* where “wear” is due to friction in my pack–I think this is probably the dominant mechanism for wear on my Hexamid, or so the multiple friction-induced holes in the stuff sack would suggest

^ I think that might be on my list to try- not sure if I want to go down or apex, but am thinking about his option of Robic at the head and foot- this would give me some splash protection and possibly eliminate the need for a bivy under a tarp

I live in the Los Padres National Forest area of Southern California and tend to do most of my hiking in So Cal or maybe the Sierras. I have an Equinox bivy. It is waterproof silnylon on the bottom and not waterproof taffeta on the top. Those properties make it entirely useless as any kind of back-up or emergency or standalone shelter of any kind. The only purpose it serves is to make up for deficiencies of some other kind of shelter.

My understanding is that a bivy is necessary if it rains to protect you from rain splashing on your sleeping bag while sleeping under a tarp. I think the only person I have ever seen sleeping in the rain under a tarp didn’t have a bivy. He looked drier than I was, and I had slept in my tent. Rain fell on me in the night, or rather rain dumped condensation from my tent on me in a fine mist that felt like rain. His tarp was not a poncho, it was large tarp. He was able to lay there in his sleeping bag in the rain under his tarp, fire up his stove and make hot chocolate for breakfast, while I had to stuff a sopping wet coffin of a tent into my pack and hike away hoping to dry out later.

I’ve heard people say a bivy can add maybe 5 degrees of warmth or possibly prevent drafts. I have noticed no such effect. Drafts are still there and I’m still cold. I think it if is cold and I have a bivy with me, the best way to use it is to use it inside my sleeping bag. I think that’s the only way it stands a chance of helping me keep warm. But when attempting this, the warmth has been minimal and the entanglement has been maximal.

You know what really adds warmth? A tarp or a tent. You’d think a tarp wouldn’t make much difference but it really does make a lot of difference. Almost as much as a tent. I have an 8×10 tarp. I can’t imagine rain would ever splash on my sleeping bag nestled way into this tarp. I can save the 6 oz or whatever the Equinox bivy I have weighs by leaving it at home. I would imagine even a poncho tarp plus a bivy weighs as much or more as a big 8×10 tarp,.

I’ve thought maybe the bivy would help in dry and windy conditions to help provide a little cocoon in which you can array some of the things you might need during the night without worrying that those things will blow away in the wind. But if your whole bed flies away, that might be a minimal benefit. I have had my whole bed fly away in wind. I’ve considered sewing tie-downs into the bivy for this purpose but have never gotten around to it.

I think the one time that the bivy actually served me was one time I went hiking on PCT section C in July. That’s the part that starts near the windfarm near Cabazon. It was 105 degrees at the trailhead at 7pm. (Side note: This is a dumb idea, don’t do it, I was dropping off someone that I had to rescue the next day.) We hiked into the night and decided to sleep on the trail. It was still in the high 90s when we decided to sleep. It was hard to sleep in such heat with any kind of sleeping bag. I don’t know about you, but lying on the ground with absolutely nothing on top of you is hard to sleep. First of all, some kind of flying insects kept buzzing my bare legs. They did not bit or sting, but they were large and buzzy and tickling me and it was bothersome. Second, just lying there with no blanket of any kind, staring up at so many stars, I felt like I’d fall off the earth into the night sky. I needed some kind of blanket to hold me down. The bivy to the rescue! I could only barely stand to have it laying over my lower legs, but that was enough to allow me to fall asleep. A few hours later I woke up cold and could use my sleeping bag.

I am planning a trip for May and I think I’m going to use my tarp. I have an 8×10 tarp and I sewed a bug net tent to go with it. I’ve only used my tarp on one trip in the past. I don’t think it was better either in weight or in general awesomeness than a decent tent, but I have it and want to use it so that’s what I’m going to do. But I really don’t think the bivy is necessary at all.

May I suggest looking at Ryan’s new review of the Tarptent AEON?

First this is an exhaustively comprehensive review with a video and stills.

Second the single wall AEON appears, at 16 oz. WITH an attached netting door and Dyneema floor, to be about the best designed Dyneema solo tent extant.

IMHO all it lacks is the option of a green or brown fly color.

GCraig- our experience I believe was due to very heavy dew (and quite possibly some condensation added to it).  With the temps as they were, you may have been better without the bivy- less soaking, more freezing- it (the lwt bivy) certainly didn’t help in that situation and possibly added to it

I have been doing high desert trips almost every November and December for the past 42 years, where the overnight lows are predictably in the mid to low 30s. With a very “breathable” bivy I always got condensation and a wet bag. When I stopped using the bivy and cowboy camped, I would sometimes get a litttle condensation on my bag or quilt, but not to the point of a wet bag. Below are pictures from two different December trips with lows around freezing, no bivy, and no wet sleeping bag in the morning. Also notice that there is a bit of water next to my campsites.

On the first trip, away from water, I slept under this large tarp due to the threat of rain. I didn’t rain but the underside of the tarp was very wet in the morning.

The next night had clear skies and the lake has a few trillion gallons of water in it. Bag was completely dry in the morning.

The one below is in Black Canyon along the Colorado River. In the morning my drinking water was partially frozen, but the quilt was dry.

You guys had more vegetation around you, but my experience is your bags would have not gotten soaked if you had not used bivies. Invest in a extra 8 ounces of down to stay warm and dry. I have mostly cowboy camped for the past 50+ years — without a soaked bag — except for most of the trips when I used a bivy in colder weather.

May I suggest looking at Ryan’s new review of the Tarptent AEON?

Some of use prefer stars as a roof instead of cloth or plastic :-)

There are a couple options/alternatives:

The SOL Escape/lite bivies or using polypropylene fabric, whether woven or nonwoven.  Nonwoven is not super strong or durable, but if gotten at the right (heavier) weight and one is at least semi careful, it works well and lasts long enough. Black is best, bit more UV resistant.

Ime it’s hard to find lightweight, woven PP fabrics though. What I have done, is buy lightweight PP baselayers (like Terramar brand) in the largest sizes I can find, cut them up carefully, and use these, though I haven’t made a bivy out same yet.

But yes, any of these make excellent bivy materials, as they have permanent DWR, are less thermally conductive, fairly to HIGHLY breathable, dry fast, and in the case of the Sol Escape bivy–reflect IR back to you which also decreases wet out.

A coffin offers better splash and wind protection than a bivy for the same ‘living’ space. Get your future pall bearers to carry it.

And yes, I prefer a tent. I’m finicky about bugs and mice and weather.

mice scamper over me occasionally, no big deal

I was sleeping and Doug said he saw a Racoon get close to me.  That’s a bit more worrying.

I’ve had a red squirrel, several mice (a couple species), and a coyote sniffing on me at one time or another. They usually run like hell when I move…lucky to see the butt end. ‘Coons are a bit worrisome…I have had them wander through camp but never under my tarp. Something to look forward to…

at Cape Dissapointment state park in southwest Washington the racoons are very agressive

I chased some away and then turned around and saw another starting into my car

They aren’t bothered by just chasing, you have to hit them with a rock or a stick.  (gently, no racoons hurt, they’re actually better off because if they get too friendly they’ll have to be dealt with more aggressively : )

The raccoons at Cape Dissapointment are easily the worst I’ve encountered out of several states. They have gumption and little regard for social mores.

I had a pair of racoons force me off of their sidewalk once near where I live. And they howl like mad if they get into a fight.

At Little Yosemite Valley for a while there was a raccoon working in tandem with a bear. The raccoon would go on ahead into a campsite or tent and the bear would amble behind if anything good presented itself. I hiked for a while one morning with a guy who’d had that same raccoon step on him during the night. Then we came on a mother bear and her cubs just outside of the campsite.

wonder why there are two c’s in raccoon.

My worst night with mice was in an area with warnings for mice that carried hanta virus. After that I decided I liked a tent with netting.

we used to have raccoons around the house.  Attracted by the cat food we left out.  All the outside cats got killed by cars or coyotes so we quit doing that.

There were raccoons.  Then they started having this weird stumbling behavior.  Then they all died, distemper I believe.  Then they developed the property behind me.  That and no cat food resulted in no more raccoons.

I once pitched my tarp (unknowingly) right over porcupine highway.  No bivy this night.  I had little baby porcupines nearly all night long coming to check me out–cute little things.  And then I heard some noise turned on my flashlight to see what was causing it….and I saw Momma Porcupine…she was bigger than a 125 pound Labrador!

HA, ha…yeah. Porkies can seem huge when they bristle up, especially at night. I stumbled across one out fishing one time. I poked with a 5′ fishing rod to get her to bristle up for me. Kinda funny to watch her antics…she was not aggressive at all, just defensive and kept turning her tail and back to me while trying to keep her head in position to see me. I walked back in the stream…not sure how she took it…

Another time I had camped on a lake and kept hearing chunk, chunk chunk chunk chunk and silence, over and over. It sort’a sounded like metal being scraped. Eventually, I had enough and wandered out to see what the hell. Turns out there was an old aluminum boat out there that someone had tarred the bottom… I caught sight of a porky waddling off and it turns out the boat was flat…I mean FLAT! They had eaten the tar and aluminum leaving the just the outer shell laid out on the ground, neat as a pin. Apparently, it would stand on the boat bottom and scrape away with it’s teeth…chunk, chunk, chunk, chunk, chunk, … At least it became a non-threat…

There were raccoons.  …  Then they developed the property behind me.  That and no cat food resulted in no more raccoons.

So…they spent all their money on the property and had nothing left to buy food?

Do eVent WPB bivys condense as much as GTX bivys?

I’d think not given that eVent directly vents water vapor W/O needing to wet the membrane as with most types of GTX.

Assuming you mean Gortex by writing GTX I don’t see much difference between the two fabrics, overall.

Generally eVent is lighter because it is made with no outer covering to keep it clean. But, you have to wash it with regular laundry and avoid fine dust & oils (it can also “plug up” with water slowing breathing.) A light fabric (like Gortex core,) it can be delicate to handle. So, it is usually laminated with a couple layers for strength. Seams are a bitch. They leak easily (though not as bad as Gortex) and are difficult to seal due to the lamination. It all ends up rather heavy, even though touted as light weight.

Reqular Gortex, having an inner/outer membrane, stays cleaner longer and doesn’t require much maintenance. For example you find it a lot on shoes/boots that don’t get laundered a lot. It is warmer since it is three somewhat thicker layers (“self” cleaning film inside/outside and Gortex layer, plus fabric laminates.) And it requires more heat to drive moisture through it. Usually a minimum four layer construction, it is quite durable, but you pay for the durability with weight. Again, due to the films, it is difficult to seal seams with tape and really needs liquid sealers to penetrate the stitching/seams to seal the compound membrane.

In both cases the two can stretch oddly when sandwiched. Both can micro-rip slightly if over stressed, being thin films. This means they have finite lifetimes. They go bad after a month to 6-7 years depending on use & care. Indeed packing, unpacking, wearing can degrade either material over rather short time periods, depending on the laminates and user. Pokes can cause micro tears in either. Using a rain jacket as a ground cloth is not recommended. It is usually sandwiched with nylon but nylon can stretch, and the thickness can over stretch the thin membrane in sharp bends. Poly stretches, too, and is heavier for the same strength, actually worse since it is thicker. Lighter means more stretch, but this is where you have problems with pokes & pulls to the membrane (along with seam sealing.) The ultra fine micro-holes of the manufacture eventually open up into larger holes and leak due to mechanical damage. Not worth the dollars in either case, in my estimation. Very popular with new hikers, though.

Offhand, I would say that eVent would be a better bivy, provided you keep it maintained. It is lighter. But maintenance can be difficult on a long two week outing or a thru hike. It is less water proof, breaths better, has less fabric to force micro-tears (from creasing,) but, it can degrade quickly in use from dirt and oils. It will breath slightly better, but, is usually heavier where any use dictates a stronger fabric.

(Interesting to look at 7D nylon reinforced with spectra grid, nothing on the market. It won’t eliminate the creasing problem but help a bit, but will mostly eliminate pokes, stretches and punctures.)

For both fabrics, I remain ambivalent. I see them as non-permanent, expensive and heavy. I think the only place I use either is on my shoes and on a stuff sack.

Eric, the short answer is yes.  Because eVent does not have the additional PU membrane, like Goretex, to help keep oils and dirt from compromising the WPB layer, it does breath better.  As to keeping it clean, a bivy is not like a rain jacket in that you are wearing and getting it dirty and such.  It just lays over the top of your clean sleeping bag/quilt so I have never worried about the need to clean it.