Bivy bags? Might be a silly newbie question here... but...

[Alittleruff]

It might be a silly newbie question here. However, I always have thought that it is better to ask the silly question, than to not ask it and remain ignorant of the answer. My question relates to "bivy bags". Does a bivy bag replace a tent? Are they kind of like a very light weight swag, or are they simply a waterproof cover for a down sleeping bag?
I was checking out this- http://www.globewalker.com.au/bivvi-bag/ among other bags and it has occurred to me that Bivy bags are generally found under the 'sleeping bag' sections of most web sites and not in the 'tent and shelters' parts.

Do you slip a sleeping mat inside the bivy like a swag? Or do you place it underneath and tempt the thing to slip from underneath you?

Last edited by Alittleruff on Wed 15 Apr, 2015 12:04 pm, edited 1 time in total.

[Nuts]

There are a lot of different options, waterproof/stand alone shelters (lightweight swags) to water resistant covers designed to keep condensation off your sleeping bag. Most are sized to take a thicker pad inside but size is another option. I'd choose goretex (or event) shell fabric if using it as a stand-alone shelter, even then some form of tarp makes the experience Much more liveable.

[Alittleruff]

What do you think of this Nuts?
http://www.campsaver.com/aurora-bivy

With this bag- http://www.globewalker.com.au/down-slee ... ltralight/

And this mat- http://www.kathmandu.com.au/sleeping-ge ... phite.html

Recipe for disaster? Or would it be ok, for overnight hiking with a group in Spring?

[Franco]

Two words to think about with bivy bags
1) rain
2)bugs

[Nuts]

The Aurora is a good bivy bag. (There's one here for.... $150- viewtopic.php?f=13&t=19091 ) you'll only get a thinner mat in there unless you are quite slim. They do have a bug screen.

I don't have any experience with those sleeping bags or mats.
Honestly, if it does rain.. unless you have it down to a fine art (and even then), you'll likely get other gear wet just getting in to the bivy. The waterproof bivies can also suffer condensation themselves (even if you don't get rain). Unless expecting a dry night in fairly elevated/airy conditions yes.. potentially a recipe for disaster without some additional cover (tarp etc). This is why there are a lot of lighter water-resistant offerings, people use them under lightweight tarps or tarp style tents. They 'breathe' better/ suffer less from condensation and save some weight (over WP bags). I still prefer Waterproof, even under a shelter, deal with some condensation but great piece of mind (in case the tarp blows away or just to sleep in the open on a nice night).

[Alittleruff]

I'm thinking about that Franco.
1. Rain, probably a chance, but more often than not it's not an issue. As long as you stay dry, then equipment can be shaken out and packed for a few hours, until you need it the next night. A tent would have to be packed away wet anyhow, so I'm not sure if a bivy bag would be more convenient (less to pack up in the wet) or less. ummm... maybe a synthetic sleeping bag?
2. Bugs. Hate them. Mosquitos suck. Bushmans, and a bug net would reduce this. I would plan to use my bug net from our pram. It packs down to nothing. Mosquitos get into tents too.
I'm throwing some ideas around. But.. I think that a bivy bag might be a great answer... but I'm in the "thinking about stuff" stage.

I'd love to hear from people who use Bivy bags to give some +'ves and -'ves so that I can weigh it up

[Travis22]

I have the US military MSS bivy and cold sleeping bag. For the money it is hard to beat. The bivy is gortex with heaps of room, bomb proof design and construction (designed for solders to sleep in them weapon, boots and all) so plenty of room for a sleeping mat etc in the bivy. I think i payed less then $50 for mine. It is however nearly 1kg, might have been 800grams but i cannot remember exactly.

It does not have any sort of bug screen and the top just flips over your head and there is a velcro patch should you wish to secure it over your head/ face. Personally ive never had any issues with bugs here in Victoria. Ive used it in the rain also, however ive always been under a small tarp. The bivy has still been wet in the morning from rain blowing in under the tarp but ive never had rain come in through the bivy.

Again, for the money its a great first option, if your really like the method of sleeping outdoors in the bivy then you can always lash out on a much more expensive option later on should you want a smaller and lighter bivy.

http://en.wikipedia.org/wiki/Modular_Sleep_System

Travis.

[andrewa]

Had various bivy bags for years. Slept in them as stand alone shelters only a few times.

Had one good night in summer on the Baw Baw plateau watching the stars; had a bad night on snow on Baw Baw with a full moon, which kept me awake much of the night, and I kept sliding off my sleeping mat - actually it kept sliding out from under me (there wasn't enough room for it inside, unless I lay perfectly straight), and the third time I slept in the snow, and got buried by 6-8" of snow that fell overnight, and it was very hard getting dressed in a bivy bag!

They were useful for sleeping in snow caves.

Wouldn't bother with one now. I cut my current one up a few weeks ago (now an ex-bivy bag), and made a shirt from the fabric.

I prefer to sleep in a tent....or occasionally on an upturned packraft under a tarp.

A

[beean]

I'd get a tent first, maybe a mid or a largish tarp you can make into an enclosed shelter. You'll find that they weigh just a little bit more than a bivvy.

Then get a bivvy when you're more comfortable with your sleep system. They're good for specific purposes.

I'm looking at getting one now, after finding out the hard way my tarp alone isn't adequate for sleeping at the base of climbing routes.

[creeping_moses]

Tent definitely first, however for some styles of walking a bivy is excellent.

I have done a number of trips, all in Tasmania and predominantly in winter, using my bivy as the sole form of shelter. I use the Outdoor Research Advanced bivy, which is roomy enough for a good thermarest mattress and a winter sleeping bag. In winter I haven't been cold but as discussed, rain isn't very fun. You need to cook and eat in the rain (i.e. full rain gear) then quickly get down to thermals/sleep gear and get into the bivy (and also secure your bag in a water proof manner) without getting soaked. This is a fine art. Some rock shelter/tree shelter is very useful and hence bivy caves are very popular.

[slparker]

Two words to think about with bivy bags
1) rain
2)bugs

3) water vapour... because we all know how well membranes 'breathe' when it is humid outside

[Franco]

Alittleruff,

You will find that most bivy user also use a tarp over it .

Now, I see you reasoning about rain but it does not work like that in practice.
If you cannot visualise it , try this the next time it rains outside your door.
make a pretend bivy out of garbage bags (bin liners) .
Two large ones , some tape and a pair of scissors will do.
In the rain, go outside with your pack , get the bivy out and place it, put you mat under or inside, get your sleeping bag out of the pack, put it inside then get into the bivy.. (take you rain gear off first)
You will be wet and remain wet.
How do you get undressed in a closed bivy ?
Where do you put your wet clothes ?

You can see next to my name that I am part of Tarptent so my comments can be taken as self serving , however it just happens that Tarptent was the brand I was using before I became part of it.
If I liked hammocks I would be pimping one of those...

[photohiker]

I've slept in bivvys a bit, have two styles:

1) RAB Ascent Bivi, 629g, made with Event fabric. It has a mossie net of sorts, but once you are inside it's not easy to read a book for instance. If it's raining, you keep dry but the outside of the bivy is wet, wet, wet. You have to be lucky to be able to take off your wet clothes and get into the bivvy dry, and you have to stash your wet clothes somewhere. Can be done, but not fun. If it's dry and there are no bugs about, then everything is great. You can lie back in your bivvy and watch the stars!

2) Katabatic Gear Bristlecone bivy. 215g. Made with water resistant but not waterproof top fabric, silnylon base. Not really suitable for use without a shelter, but if you were certain it isn't going to rain you could chance it. I use mine with a tarp (MLD Trailstar) which is an open mid style fly with no door. This bivvy has a better shape and bug protection, and is very good if you want to read or watch the stars through the fly doorway etc when there are bugs about. A bit of spray from rain is not an issue, and it seems to vent better than the RAB. I have seen condensation in the RAB, but never in the Bristlecone.

How do you get undressed in a closed bivy ?

Outer layers off and stashed, then hop in the Bristlecone. There is room in there to get changed although it requires minor contortions. Is it slower than in a tent? yes. With a tarp, I don't bother changing inside the bivvy. I keep socks under my SB so they dry some from body heat, rest of clothing gets rolled up at one end. Works for me.

[Aidan]

It might be a silly newbie question here. However, I always have thought that it is better to ask the silly question, than to not ask it and remain ignorant of the answer. My question relates to "bivy bags". Does a bivy bag replace a tent? Are they kind of like a very light weight swag, or are they simply a waterproof cover for a down sleeping bag?
I was checking out this- http://www.globewalker.com.au/bivvi-bag/ among other bags and it has occurred to me that Bivy bags are generally found under the 'sleeping bag' sections of most web sites and not in the 'tent and shelters' parts.

Do you slip a sleeping mat inside the bivy like a swag? Or do you place it underneath and tempt the thing to slip from underneath you?

Hi Alittleruff,
I've done some cycle-touring using a bivvybag and tarp with the longest tour being in the vicinity of some months where I biked from Mudgee NSW to Perth, with a months recuperation in Adelaide in between to get over the worst of some fractured ribs from a fall outside Mildura.

Handy for situations where there is a benefit for low bulk ie. my bivvybag/tarp combo take up less room than my only tent of the time which was a Macpac Minaret.

There are different styles of bivvybag, but my one was utilised by placing my sleeping mat underneath, but on top of a groundsheet.
I never found it to slip out or me to roll off that I recall.

In summer I tend to not bother with the tarp but in colder months I use the tarp to hinder frost which freezes moisture on the bivvybag and worsens its susceptibility to condensation and moisture trapping, creating the potential for a damp sleepingbag which isn't what you want in winter.
The tarp gets used if rain is likely in any season so if its grey and cloudy or there is rain forecast, I put up the tarp.

I would generally break camp and head off at dawn to take advantage of the cool and when I break for lunch, I'd hang both the sleeping bag and bivvybag from a tree to dry any potential moisture in either.
I found my lunch break adequate for the task so never needed an alternative.

I tend to camp wild and try to use campgrounds/caravanparks every 3 to 5 days to conserve funds.
After this time has gone past I get pretty desperate for a good shower and using the washing machine.

I also use a tent for some trips and I enjoy both my choices of Macpac Microlight and Minaret.
The benefit of the bivvybag for me is where I can put it down to sleep. It has the advantage of size in that I can put my head down to sleep in places I couldn't pitch a tent. I need only a very small footprint amongst the roadside scrub to grab my sleep and this is especially relevant with regards low overhanging branches which might otherwise damage a tents fly.

Also the bag is less visible which is important for avoiding unwelcome visitors of a human kind closer to towns (or anywhere for that matter)
I've managed to stay in some unusual places without attracting attention and thus avoided needlessly emptying my meagre wallet on camp fees, gaining a much better meal and beverage for my troubles.

The NSW to WA trip saw the demise of my then ancient and very well used Macpac bivvybag and by whingeing in a thread in this forum, the company rep, at the time, Cambell (Blacksheep), kindly found me a brand new one in green which was the sticking point for a purchase.

I've yet to christen the new one but its materials on paper at least appear vastly superior to the old one and I'll be extremely happy if it get the same lifespan out of it. It even appears to have better materials, in the floor at least, than the latest model in that it the same floor panel as Macpacs tents (torrent wear).
It does lack the hoop/pole to keep the fabric off ones face, like my old one but I find a couple of days use quickly overcomes any initial claustrophobic feeling.

I find a bivvybag a worthy addition to compliment my collection of sleeping shelters with its own benefits/strengths and I'm glad to have it.
It can and will replace a tent in certain situations (IMHO) but having both offers the best of all situations.
Its possible now I've bought a bicycle trailer to haul water, that I'll have room to carry my bivvybag as well as my tent to enjoy the best of both worlds.

[Alittleruff]

Thank you so much for all your valued replies. I find the idea of bivvy's liberating. Just roll them out and sleep under the stars. No messing about with guidelines, pegs and ropes. But still, I realize that I may not be "hard core" enough for that kind of roughing it. I think about the loads of people that have done this kind of thing before, without the kind of expensive equipment we all tend to put in the 'must lug around' with us lists. The first Australian settlers would have thought that a Bivvy was "Glamping". But hey, they were tough!

Aiden, your tales of bivvy camping are inspiring and informative. I appreciate your advice on how to dry out sleeping bags and the bivvy between uses. And the variations, between tenting, bivvy and having a tarp set up.

Photohiker, and Travis thank you for your bivvy suggestions. Much appreciated. I will look into these options.

The bit on how to get dressed inside a Bivvy I find quite amusing. As a girl, well.... girls in general are very crafty in getting dressed and undressed without anyone noticing. And, if there is no one around, well, you just get dressed as quickly as possible. It's kind of amusing, because you have to get undressed every time you go to the toilet, in the open... even if it is raining. If raining, I'd probably stand under a tree. I'm not looking at camping in suburbia. However, one of my mates camped in my front yard once. He slept in a swag. He sleeps naked. My poor elderly neighbor got a little bit more than she was expecting in the morning! LOL.

I really like the idea of the Rab ridge master Bivy. But cannot find much in Australia, and what I have found is exy. It still has a few ropes and pegs, but looks like it would be ideal for 1. Postage for such a light item from OS surely can't be much? Or maybe a simpler Bivy like the army one suggested above would do the trick. Thinking this over. I might be over thinking it!

[kitty]

http://www.cotswoldoutdoor.com/au/rab-r ... _colour=98

[Franco]

BTW, my comments were about the type of bivy posted by the OP in the original post, not the tripod bivy like the Rab Ridge Rider
(I have 2 bivys...)

[north-north-west]

The first Australian settlers would have thought that a Bivvy was "Glamping". But hey, they were tough!

They had no choice. Toughing it out was the only way to survive. But clinging on to survival is not why we (I) go bush.

[Nuts]

I tried the RAB nestor/ridgemaster bivy (Alr), similar though with a foot pole and side zip.. (for just a little more weight). 'Hooped' gives a little bit of room to get dressed. Unfortunately that is only an advantage while ever the inside is dry. I was interested in the concept of breathable fabric as even without the poles you should be fine using it as a flat bivy but then it's not likely to collapse and the event didn't seem to handle the condensation well, as well as it does in the Rab Alpine bivy- ended up thinking the fabric needs to be close to your body to 'breath' well & not suffer so badly from condensation inside.

[Franco]

"ended up thinking the fabric needs to be close to your body to 'breath' well & not suffer so badly from condensation inside"

No science at all behind my comment but I think that it has to do with temperature differential.
The internal temperature needs to be significantly higher than the outside one to push water vapour out, so the more air space you have the less likely it will happen.
But again, I am just guessing.

[andrewa]

That's right Franco. That's why the goretex shells on sleeping bags in the 80s were a passing fad. A decent sleeping bag should insulate so well that the outside fabric is at air temperature, so a goretex shell didn't breath well - although it did keep the outside moisture out.

A

[Empty]

I had a gortex bivvy in the 80s and absolutely hated it. I paid a small fortune for it and only used it half a dozen times. They are nothing like a swag in reality (which the pioneers used)- very restrictive.

If you need to get up in the middle of the night to visit the sandbox they are a real pain and mostly you need to carry a tarp in case of rain or snow so you may as well carry a tent.

The other thing which may not have been mentioned is the " kelvinator effect". This is where frost forms on the outside of the bivvy and then a breeze later picks up giving you a real chill because you are essentially coated with a frosty shell.

If you sleep in one you'll soon realise why caterpillars turn into butterflys- to escape that feeling of restriction.

[Orion]

Never mind.

[Nuts]

Ah, Orion, a fine album! (and word..)

Did some reading -about changing dew-point Franco, just the distance allowing thermal gradient/ the vapour to condense too soon (in certain conditions)? The Alpine Bivy can get pretty icey outside but relatively dry inside (by comparison). I wanted to like both of those bivy/tents but my little tent weighs less than either and sleeps two (in a pinch).. so they weren't going to get a lot of use. If you are nimble and 'well managed' and mostly do single nights in good forecasts I can see they are perfect for some even possibly without other shelter. MLD make a very light weight eVent flat bivy.

[Aidan]

I had a gortex bivvy in the 80s and absolutely hated it. I paid a small fortune for it and only used it half a dozen times. They are nothing like a swag in reality (which the pioneers used)- very restrictive.

If you need to get up in the middle of the night to visit the sandbox they are a real pain and mostly you need to carry a tarp in case of rain or snow so you may as well carry a tent.

The other thing which may not have been mentioned is the " kelvinator effect". This is where frost forms on the outside of the bivvy and then a breeze later picks up giving you a real chill because you are essentially coated with a frosty shell.

If you sleep in one you'll soon realise why caterpillars turn into butterflys- to escape that feeling of restriction.

You seem a little down on bivvybags.

I happily acknowledge they are not for everyone but (IMHO) "might as well carry a tent" comments appear to attempt to negate any practicality.

I dispute your "kelvinator"effect which I put down to a sleeping bag which could maybe benefit from either a higher quality or higher gram count of down/fill

[Alittleruff]

So after all that thinking, I finally did buy a bivy bag At 1.3kg I'm rapped that it will lighten the load in my pack. I've tested it out on the lounge room floor... yeah I know, I know. And it fits my mat in comfortably, fits me in comfortably and has a hoop to keep the bag off my face.

I ended up buying it on the spur of a moment while at Aussie disposals, for $100. It's a x-dutch army bag. It's a throw down, done kind of style that I like. No setting up rope lines galore. A small hoop will keep the fabric off my face. I like the idea of basic.

[flywire]

Hey Alittleruff - I'm probably alotruff.

I wanted a tent with a bit of room and settled on a bivy sack. Only a bivy fan would recognise this as the perfect solution!

I used a bivy with a 1.2 x 2.4 m piece of poly tarp cut from a roll for a few months and camped on a horse blanket. (My gear included a 1.5l orange juice water bottle, single pot, pocket knife, spoon and a single set of clothes plus winter underwear.)

I enjoyed the weight but my implementation wasn't good enough with the weather ranging from blazing heat to snow. I'd have loved condensation to be my moisture problem but it wasn't because the sides were only press studs and I pulled the tarp over when it rained. I always got up early, layed the tarp down then bivy (or the other way round) and sleeping bag then rolled them up. Unfortunately my problem was the feathers sucked the moisture through the gortex or off the tarp into the sleeping bag. There were no trees or sticks to lift the tarp where I was.

My idea of being uncomfortable is carrying weight - so I'm still a bivy fan.

1.3kg?

[Oncall]

Used just a bivi bag extensively with a good mat and sleep bag. Great for very fast deployment of shelter and sleep, fast pack up and go, light, small pack size, very durable. Nice and warm even in extremes, but you really need excellent camp discipline in wet weather. If you use with a tarp too then you may as well get a tent as the weight soon adds up. With discipline you can stay dry and warm in a bivi even in the wetest of weather, but it takes practice and discipline. I use my large pack cover and a strong durable bin bag to keep kit dry and cook under if need be. The ones with a hoop are a bit more comfortable, and a bug screen is wise. Gortex is crucial or condensation will ruin your day and night. I also use with synthetic sleep bags only so they stay warm even if damp.

[Alittleruff]

The bivvy worked great! McCallister Springs VIC, very cold night. It did not rain though. I was very happy, with the exception of some zips that were hard to pull. But for $100, I was a happy camper. Easy peeasy.

I may be looking at a tent later though... I wonder if I can reduce the weight from 1.3kg and also increase the capacity to have more people?

[jfullertonharvey]

I may also be asking a silly question.
But with a bivy like an outdoor research bivy. How are you supposed to breathe with all the zips done up?