Bivi Bag Setup

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 glenn0010 05 Feb 2021

Hi All,

Followign several posts about going more light weight, I'm looking at getting some bivi stuff to reduce weight.

What kind of set up works best for you guys?

Hooped bivis - standalone, less faffy? Heavy? Can get a terra nove laser for same weight? Can pitch pretty much anywhere. What about condensation?

Open topped bivi with tarp on top - More breathable, less condesation? More faffy, need practice with tarp and les sutied to wind?  Lighter weight?

Another question is I have a synmat HL winter, it's 9 cm thick. Does this give enough height for sleeping bag inside the bivi?

I've never done this so have no idea of what's important.

Cheers 

 Dark-Cloud 05 Feb 2021
In reply to glenn0010:

Erm, well a TN Laser is £450 so that hardly a comparable alternative!

When and where are you planning on using it ?

Post edited at 09:52
OP glenn0010 05 Feb 2021
In reply to Dark-Cloud:

Yes definetly, it's way too expensive for my taste so that's why I'd perefer a bivi. 

As for where, I'd like to use on the pennine way in the summer for sure. I'd also like to use it on the mountains in snowdonia and possibly beyond. But also would like to use it for winter trips as well, as I try to get out all the time, 

I dream of using it in summer in the alps, but I think that's a bt too far ahead. Biviing seems like an aquired taste so there's only one way to ifnd out really

 artif 05 Feb 2021
In reply to glenn0010:

For a start I would pick up a cheap ex army bag £35 on a well known auction site get a tarp and try it out locally/in the garden, to see if it you like it. 

I added a hoop and bug screen to my army bag for a bit of extra comfort and little cost.

For summer you can get away without the bag, just a tarp, as long as you check the weather forecast.

Go light (expensive) when you know what you need/like

 TobyA 05 Feb 2021
In reply to Dark-Cloud:

Some hooped bivvies are bloomin' expensive! They are also not particularly light, I often wonder why not just get a light tent instead.

 Dark-Cloud 05 Feb 2021
In reply to TobyA:

Agreed, if it was a choice I would go light tent every time over bivy, bivy to me is a luxury for a nice late spring or early autumn evening

 ScraggyGoat 05 Feb 2021
In reply to glenn0010:

Bivying in bad weather is a pain, and is when a hoop is nice to keep the fabric off your face, you also have a better chance of keeping the weather off while still having some ventilation, so is less claustrophobic and less condensation.  Bug net is invaluable if using in summer.

Generally if good weather and you can go high bivvying for a night or two is fine.  If bad weather by the time you have added the weight and faff of a tarp you'd be better off with a tent which will keep you far drier, let you change clothes, and cook ect. Get a cheap bivi for very good weather (unless you plan to bivi on ledges, or behind boulders in poor weather) and a cheap 1 man tent. Current really light weight tents go for a fortune, but the last generation. c. 1.5 kg's can be got second hand for 100-150 quid.

Post edited at 10:38
 TobyA 05 Feb 2021
In reply to glenn0010:

> As for where, I'd like to use on the pennine way in the summer for sure.

Give it a go by all means but bivvying can get miserable fast if it starts raining. Condensation inside the bag wetting your sleeping bag can be quite a major issue, fine for one night out not great on multiple nights. In the summer midges can make bivvying very unpleasant. I've used a tarp quite a lot but in the UK with few trees in upland areas they can be tricky to pitch well, and you have to carry a pole or poles if you don't use walking poles or if you aren't bikepack and can use your bike. If you take a tarp AND a bivvy bag (and possibly even a pole, you may well be at the weight of light tent. If you are somewhere lonely and remote, privacy isn't a big issue but being in a bivvy bag on a campsite, even with a tarp as well, feels a bit weird, but if you are doing a multi week walk, wanting a shower and a proper loo and maybe a washing machine at some point seems quite likely.

I've spent many nights in bivvy bags in all sorts of conditions. Some have been among the best outdoor experiences I've had - but then again if you are sleeping out under a canopy of stars and its heading towards -20 you don't need a bivvy bag - just a good sleeping bag. But some nights in bivvy bags have also been probably the most miserable experiences I can remember!

 TobyA 05 Feb 2021
In reply to glenn0010:

UKC/UKH gear editor Dan will be able to confirm this but I think there might be a UKC/UKH bivvy bag/tent review in the offing. I'm not involved but I think it might be on the schedule - although obviously reviewing stuff for overnights is particularly difficult right now. 

You might be interested in a review I did last summer https://www.ukclimbing.com/gear/camping/tents+bivvys/black_diamond_distance... Is it a tarp? Is it a tent? No! It's super-tarp-tent-bivvy-thingy! Anyway, it gives you the idea that these categories are rather fuzzy on the margins.

 DaveHK 05 Feb 2021
In reply to glenn0010:

Another vote for a light tent over a bivi. Hardly any heavier if not in fact lighter depending on set up and massively more practical/comfortable.

 Basemetal 05 Feb 2021
In reply to glenn0010:

In Scotland I prefer a tent 9 times out of 10. If it's a nice enough night you can sleep outside the tent, and as soon as you add a tarp you lose the sky anyway.

The closest I usually get to bivvying is when I just take the tent flysheet and sleep with the doors tried open. Some tents particularly lend themselves this, eg the  MH Optic.

https://www.trekkinn.com/outdoor-mountain/mountain-hardwear-optic-2.5/13627...

With other tents you can get the weight to match an army bivvy bag & tarp set up.

In reply to TobyA:

Yes Toby's quite right, I'm working on a group test of single person tents and hooped bivvies. It's scheduled for summer publication but I may be able to bring that forward a bit, lockdown and weather permitting.

I'd echo most of what Toby says about hooped bivvies versus tents. Condensation, privacy, warmth, weather protection, midge madness... a bivvy falls short of a tent in a lot of important areas. If I had to pick one or the other then I would go for a tent.

And once you start thinking about adding a tarp then personally you've lost me: that's coming close to a tent in weight and for livability it's never going to beat a decent lightweight tent. I know Toby goes tarp-ing out of choice but I've never been a fan. It's the UK, there will be wind, rain and/or midges more often than not.

Though a bivvy is a very considered choice and not one I would be making in wet or iffy weather, when it's good it is very good. I would save it for mini backpacking missions of a night or two, with a good forecast. Or things like the Cuillin Ridge: albeit I'd go as light as poss there, which likely means a simpler non-hooped bag.

It's worth noting that the very lightest hooped bivvies really are light though. I've got an OR Helium Bivvy here that weighs under 500g. But you get less for your money than with a tent of similar price (c.£200) so you are paying in monetary terms for that weight saving.

  

OP glenn0010 05 Feb 2021
In reply to Dan Bailey - UKHillwalking.com:

So Looks like everyone is reccomending a decent light weight tent. For me less faf is always a huge epsecially in bad weather. 

What reccomendations would people give for a decent light weight tent? I got a Terra Nova Helm 1 which is good for more laid back adventures and quite durable and roomy but at 2kg it's not light. 

Getting something <1 kg would be great, Tera nova laser seems to be a benchmark but it's quite pricy, are there any cheaper alternatives?

I've never used trekking poles so, am not sure about the light weight trekking pole tents either.

Cheers

 Basemetal 05 Feb 2021
In reply to glenn0010:

>I got a Terra Nova Helm 1 which is good for more laid back adventures and quite durable and roomy but at 2kg it's not light. 

Try it without the inner.

What else are you carrying? (the tent might not be the cheapest/easiest weight saving.)

Post edited at 11:46
 Jim Lancs 05 Feb 2021
In reply to glenn0010:

In about 1980, a colleague expanded his small tent / waterproof manufacturing company by buying a Goretex taping machine. It was then open season for everyone to make anything we wanted as a way of generating lots of designs and doing rapid testing. We made everything in Goretex: some were a success (cagoules), some stupid (rucksacs?), some just didn't work (tents) and some, like bivy bags, seemed to be the answer to all our prayers -  light, waterproof, compact, flexible . . .

By the end of that summer we were ready for 'the big lightweight, gear test' - a long bike trip through the Pyrenees and on to the Picos and Costa Verde. Everything had been whittled down to the minimum and jammed into just saddle and handlebar bags, both waterproofed by custom fitted goretex liners!

And then it started to rain. And continued non stop pretty much for the whole time. We had to buy a cheap tarp in a hardware store to cook under, some string for guy lines, picked up tent pegs off the ground in the campsite to help pitch it, then found some plastic sheeting to act as a groundsheet as the bags got filthy and heavy in the mud . . etc.  In the end our 'lightweight bivi gear' weighed more than any tent we had (even a cotton Vango). 

We've still got goretex bivy bags in our camping arsenal, but only for when using a tent is impossible. 

 phizz4 05 Feb 2021
In reply to glenn0010:

I've used a tarp very successfully in the alps, instead of using an overcrowded hut as a base for a peak the next day (Grand Paradiso, Tour Rond, Domes de Miage) but only for one or two nights. The weather was always settled, though (otherwise we wouldn't be heading up high), and an open bivy would have been just as successful. We used to use tarps when on a backpacking weekend, and never got wet even without using a bivy bag, but we knocked that on the head when we became more aware of the prevalence of ticks. Now we use lightweight tents, and mine has a home made white nylon footprint so you can see the blighters crawling towards the tent door. I wouldn't have a problem using a tarp without a bivy bag in Autumn and Spring, if you pitch it correctly you can stay dry, but for no more than 2 nights in a row probably (getting old and I like my comfort). I think a tarp would be great for walking coastal paths.

 Liam P 05 Feb 2021
In reply to glenn0010:

I have an Alpkit Hunka XL which is great and only £65. Military bags are good and cheap, but big and heavy (room for boots & weapon etc).

If you’re going down the hooped bag route then you may as well use a backpacking tent.

Tarps are pretty useless in my opinion. If it’s light rain then a Bivi Bag is enough. If it’s grim then they won’t keep the rain out and you’d be better off in a tent.

My suggestion would be to skip the tarp and buy a light tent and Alpkit Hunka Bivi Bag.

Tent for the Pennine Way/Snowdonia/Scotland in summer. If it’s wet and windy you won’t want to Bivi. If it’s dry and still you won’t want to Bivi (midgies).

Tent for winter plus a Bivi Bag to keep the snow off your sleeping bag. Although, if you can make one, snow holes are 100% more comfortable (will also need a Bivi Bag).

If the freezing level is low then Bivi Bag for the Alps. Light/fast/Milky Way etc.

The Alpkit Kloke was peddled as the upgraded version of the Hunka but I’ve heard the zipped opening is at chest level so it pretty useless!

 Rick Graham 05 Feb 2021
In reply to glenn0010:

> What reccomendations would people give for a decent light weight tent? 

Make sure its big enough. A lot of lightweight tents are sized minimally  to keep the weight down.

Touching the sides or end on a wet night will usually result in a wet sleeping bag.

A light bivi bag is often needed inside a small tent to keep a sleeping bag dry, more weight but often lighter than carrying the water absorbed into a wet bag.

Post edited at 11:51
 Andy Manthorpe 05 Feb 2021
In reply to glenn0010:

Perhaps something like a Trekker Tent Stealth would suit you.

http://www.trekkertent.com/home/17-tents

 nniff 05 Feb 2021
In reply to glenn0010:

 A tent is more civilised.  A bivvi is more robust.  In any temperate zone, a synthetic bag is very, very sensible.  If it rains, roll over to put the opening out of the rain. Mat goes outside the bivi so that you can roll over. 

If you take a tarp, you might as well take a tent.  Cooking in wind and rain can be challenging - keeping dry stuff dry, flame alight, fingers uncooked, cleaning pots etc. Trangia invaluable in this regard - Put a rock on top and leave it to get on with it.

 DaveHK 05 Feb 2021
In reply to Andy Manthorpe:

> Perhaps something like a Trekker Tent Stealth would suit you.

I love mine but you'll wait a looooooong time for one just now. He may actually have stopped taking orders.

 DaveHK 05 Feb 2021
In reply to nniff:

>  Trangia invaluable in this regard - 

But he wanted to save weight.  

 crayefish 05 Feb 2021
In reply to glenn0010:

For years I've used a double hooped bivi made out of eVent... only 600g and I've used it is some winter storms without issue.

Its the Marmot Home Alone bivi.  Can't rate it highly enough due to its light weight and enough room inside not to get claustrophobic.

However, a pertex sleeping bag is handy as in very low temps your breath condenses inside and forms ice.  Knocking the wall causes it all yo drop onto your sleeping bag.

 EdS 05 Feb 2021
In reply to glenn0010:

LanShan 1 3F UL

Popular with the US ultralight / thru hike crowd

https://www.aliexpress.com/item/32974615302.html?src=google&albch=shopp...

Post edited at 13:20
 dread-i 05 Feb 2021
In reply to glenn0010:

> What reccomendations would people give for a decent light weight tent? I got a Terra Nova Helm 1 which is good for more laid back adventures and quite durable and roomy but at 2kg it's not light. 

A lightweight tent, sub 1Kg,  is going to cost you £250+. Is it worth paying that much to save 1Kg?

Are there other sacrifices you could make? Take a water filter and only carry 500ml of water, rather than a liter? Take less food and clothes? Do more press ups, so 1Kg isn't a big deal?

As for a tarp I found this: https://www.amazon.co.uk/dp/B088M2PR2T/?coliid=I2S4BHIMLZ5UZE&colid=QKR...

Condensation would make it be useless as a tent. However, if you were to open it out, you've have a cheap, light tarp. I don't suppose it would be quiet. A couple of bits of string, some pegs and you'd be set. The other one is tyvek wrap, they use in building. Apparently very popular with the light weight bivi types.

 PaulJepson 05 Feb 2021
In reply to glenn0010:

I used a tarptent when I did the Pennine way in 2017. All I can say is that I would have had a f*cking miserable time if I'd been biviing. 

 Basemetal 05 Feb 2021
In reply to glenn0010:

If you don't have much experience you can learn a lot with nights in the back garden (if you have one) or micro-adventures nearby. Even now, or especially now, while the weather is quite entertaining...

 TobyA 05 Feb 2021
In reply to Jim Lancs:

I'm pretty certain that Mountain Hardware had a rucksack made of eVent or Outdry a few years ago - I do remember think WTF? Short of putting a puppy in there, why do you want a breathable rucksack. So great to hear they weren't the first people to try a completely ridiculous idea!  

 LucaC 05 Feb 2021
In reply to glenn0010:

I think I've done overnight trips with just about every combo of bivis apart from with a tarp (not many places to easily hang one in the mountains).

If I'm going for one night and I know it's going to be dry, I think a sleeping bag and mat is the best minimal combination. I'll add a lightweight waterproof bivi bag if I'm worried about the weather/want some more warmth or wind protection/want to protect my thermarest from the ground. 

This setup works for multiple nights but only if it's dry/you can find some natural shelter/can dry your kit in the daytime if necessary.  

Hooped bivis feel like luxury in comparison to a standard bivi, but they're quite a lot heavier without really that much more useful space other than feeling nicer to lie in! It's still hard to get changed in one or cook etc.

I've used a MHW SupermegaUL 2 for loads of 3 season overnight trips, and that for me gives the best of being super lightweight and still a useful space to cook, keep your kit out the rain etc. I think that it was £200ish in the sale and maybe 1.1kg (only slightly heavier than a hooped bivi). 

 TobyA 05 Feb 2021
In reply to nniff:

> If you take a tarp, you might as well take a tent. 

I wouldn't agree with that, at least not 100 percent. Yes there are some ridiculously light tents out there but a) they can be ridiculously expensive and b) they can be laughably small for a supposedly one man or even 2 man tent. My comfy and not too expensive 1 man tent is a shade over 2 kgs all in https://www.ukclimbing.com/gear/camping/tents+bivvys/msr_elixir_1_tent-1139... and my lightest one man 2 layer tent is 1329 g full weight https://www.ukclimbing.com/gear/camping/tents+bivvys/macpac_sololight_1-per... . The Macpac is a great little tent but it is small and in rough weather storing wet gear and so on is tricky. You can see my tarp in the first picture (under it) and in some subsequent pics in this review https://www.ukclimbing.com/gear/camping/sleeping_bags/lightwave_firelight_2... You can also see it packed up with a load of kit in a handlebar mounted bag in one the photos too. The tarps feels palatial compared to a one man tent, but even with pegs and guys and tyvek groundsheet is well below half the weight of the Macpac tent.

I've also used in some relatively rough winter weather, but it definitely takes more experience to pitch well. I've had it for well over a decade, and it was just a cheap one a mate grabbed for me from MEC when he was in Canada, there are definitely lighter and more refined designs around now too.

Post edited at 14:31
 TobyA 05 Feb 2021
In reply to EdS:

Have you bought one Ed? I'm quite tempted but have never bought from Aliexpress before, so not sure do you get charged VAT and import duties when it arrives and so on?

 Jim Lancs 05 Feb 2021
In reply to TobyA:

When a material is so 'miraculous', it's easy to think it will improve almost anything.

When we were away sailing in the late 80s, we were invited to visit with a couple who had recently retired from very senior positions on the medical side of WL Gore. Their boat was chocka with Goretex - they had clearly had free rein in the factory remnants box of materials as well as been given one of every product ever conceived in Goretex for their retirement present. Even the curtains were Goretex.

We were particularly envious of the beautiful fitted Goretex covers on all their bunk and seat cushions. It seemed to make so much sense - the perfect way to keep them dry at sea without the clammy unpleasantness of our PVC covered ones.  

Then nearly 20 years later, another manufacturer started to pitch their version of a semi-permeable membrane upholstery material to the same market. But boy, did they get burnt. It was an expensive option, but after a year or so, the complaints started to roll in. The foam and padding inside these cushions had all started to become a stinking mess of wet, mould ridden, foul smelling decay. Even on the boats that had never been out in rough weather! After a bit of thought it's obvious that when you sleep on these cushions, the warm and humid air between you and the mattress, became the 'driver' to push the moisture through the semipermeable membrane and into the foam. But once there, there was no mechanism for this moisture to get back out of the sealed cushions. The membrane was in effect a one way valve for collecting collecting sweat and body odour.

 olddirtydoggy 05 Feb 2021
In reply to glenn0010:

Only place I'd use a bivi bag is on the Cuillin ridge. When we've successfully complete it, we'll be selling off both our hooped bags and going back to the tent. The most  miserable night I've ever had was in a 'body' bag, never again. Rain causes heaps of condensation.

1
 Run_Ross_Run 05 Feb 2021
In reply to glenn0010:

Just get yourself a lightweight twin skin tent. Save yourself the hassle. 

👍 

 Robert Durran 05 Feb 2021
In reply to glenn0010:

There is a time and a place to bivi and a time and a place to camp.

Biviing is always going to be less comfortable except in good weather and there will always be condensation which is going to make a second night less comfortable unless the weather allows stuff to be dried. Biviing is going to be lighter and more flexible; you can bivi just about anywhere but a tent needs a decent spot to put it

Camping is great but nothing quite beats lying in a bivi in the hills looking straight up at the stars with the fresh air on your face.

 johnzxcv 05 Feb 2021
In reply to glenn0010:

The Book of the Bivvy by Ronald Turnbull is worth a read

 EdS 05 Feb 2021
In reply to TobyA:

I got one 2nd had.

I normally use an old bivi bag - bern closed doesn't bother me d I usually end up with sleeping bags hoid over my face anyway. 

Got it for when the dog comes with me when too cold /damp /midgy for him to sleep in the open

Hard to beat for the price if :

A) you carry poles anyway 

B) seal the seams

 damowilk 05 Feb 2021
In reply to glenn0010:

I’m not adding much that hasn’t been said up-thread, but nowadays I’d only take a bivvy if I anticipate there won’t be somewhere to pitch a tent. That to me is the main (only?) advantage of a Bivvy bag: if you can lie down you can sleep there. I’d still bring a micro tarp for the head end, I always take poles so putting it up is usually not an issue. Once or twice I’ve bivved in a pair and we’ve shared the micro tarp at our head end.

I’ve only ever got on with a highly breathable material: PU lined nylon or pertex(plus) and I’m bathed in sweat a few hours in. Only goretex or eVent seems to work for me, which pushes price and weight up. And here in NZ I’d only go when it’s cold, high or windy enough to avoid sandflies. 

 StevieH 06 Feb 2021
In reply to glenn0010:

Hi Glen, I have used a MacPac microlight for years now. They are not the lightest by any means nowadays but are sturdy when pitched properly. A massive plus for me is there is enough room inside for you and all your kit easily inside. You can fit a bag in the vestibule and still have room to cook in grim weather with care. You can have a solid inner or unzip to a full midge net.you can pitch it as one or just take the outer for your tarp experience.

You can also pick these up pretty cheaply.

my only complaint with modern MacPac tents is they have lost their bomber ground sheets!

 Dr.S at work 06 Feb 2021
In reply to TobyA:

> I'm pretty certain that Mountain Hardware had a rucksack made of eVent or Outdry a few years ago - I do remember think WTF? Short of putting a puppy in there, why do you want a breathable rucksack. So great to hear they weren't the first people to try a completely ridiculous idea!  

I’ve got one - MH scrambler 35 - it’s a really good bag, lightish at 808g, waterproof and bomber. Has those stretchy outside pockets and I’ve used for 3 night trips in summer. Obvs discontinued now.

 Basemetal 06 Feb 2021
In reply to Dr.S at work:

Me too, well, the Scrambler 30 in Outdry.

I figured the thinking for rucksacks was simply 'waterproofing' rather than 'breathability'. Especially from the early days when Gore's membrane or Event's structure was a step change in waterproofness compared to applied proofing and fragile coatings.

 Dr.S at work 06 Feb 2021
In reply to Basemetal:

Yes - the inside looks really robust I’d never really thought about the breathability angle.

 Root1 06 Feb 2021
In reply to glenn0010:

I'd go with a lightweight tent. However the lighter you go the less robust they are,  (e.g. T.N. Laser) and they generally perform less well in the wind. Pyramids such as the Mountain Laurel  Designs Duomid, and Locus work well and are lightweight. A more robust relatively cheap and semi Geodesic tent such as the wechsel Exogen would be a decent choice although you pay in weight for the comfort and stability. (1300g)

Tunnel tents are a good winter option but are difficult to set up on rocky terrain.

Post edited at 12:46
 TobyA 06 Feb 2021
In reply to Basemetal:

I think almost all half decent rucksacks are made from completely waterproof material these days, it's only stitching and zips where water can possibly get in. I of course still pack anything sensitive inside a dry bag (moved on from tesco bags for everything because we don't live in a world of endless plastic carrier bags from the supermarket anymore!) but I don't really remember having problems with water getting into a rucksack in recent years.

 Basemetal 06 Feb 2021
In reply to TobyA:

True, stuff has moved on a bit, and even MH have moved on from Outdry now.

 bouldery bits 06 Feb 2021
In reply to glenn0010:

On the occasion that I bivvy, I use an ex army GTX bag I got for very little money many years ago. It ain't perfect but relatively bomb proof and, being a shorty, I can stuff my kit in the foot end before putting me in.

I see bivvying as more of an experience than a practical thing. I might think, 'Oh, it's nice. I'll go for a bivvy!' If I'm doing a trip with a particular aim or training target it's always tent.

 tehmarks 07 Feb 2021
In reply to glenn0010:

Everyone seem to have covered the obvious points in this thread, but one thing that no one ever manages to convey in words is just how miserable bivying in shit weather is. Even if you do stay perfectly dry you'll be constantly paranoid that your sleeping bag is soaking through because it's impossible to tell the difference between the sensation of cold from water on the outside of your bivi bag and the sensation of cold water actually wetting things through. You won't sleep, and you'll vow the next day to never do it again (before promptly forgetting). It's a great activity if you need to build your character, but as an enjoyable pastime it's utterly poo.

https://www.ukhillwalking.com/forums/hill_talk/your_worst_sleeping_experience-...

For me, a bivi bag is for when it's important to be lightweight and the forecast supports it. Occasionally, despite best efforts, you'll still have a shit time. Hooped bivis are a fallacy in my view — they offer little of the weight advantages of a minimal bivi bag, and little of the advantages of a tent. They're a poor middle ground.

In comparison to all of that, a lightweight tent will see you existing in relative comfort and luxury.

 Jim Lancs 07 Feb 2021

In reply to tehmarks:

> For me, a bivi bag is for when it's important to be lightweight and the forecast supports it. 

> Hooped bivis are a fallacy in my view — they offer little of the weight advantages of a minimal bivi bag, and little of the advantages of a tent. They're a poor middle ground.

I think you're probably right. And the other irony is that if the forecast suggests it might be a perfect night for sleeping out with an uninterrupted view of the night sky - you don't need a bivi at all.

So your real choice is small tent or no tent.

Post edited at 14:42
 tehmarks 07 Feb 2021
In reply to Jim Lancs:

Totally agree, but I have found out to my cost more than once that forecasts are just that — forecasts.

Post edited at 14:47
 GCO 07 Feb 2021

Back in about 1985 (I think) I was solo trekking in Garwhal and had opted for super lightweight. I spent a small fortune on an all gore tex bivvibag and was just further up the hill from Gangotri where I had apparently eaten something dodgy.

Anyway, long story cut short:

beware of difficulties escaping a simple bivvibag in a desperate hurry when you’ve been tossing and turning and somehow the zip and Velcro opening had migrated underneath you.

if I’d had a knife with me, I would have cut the thing open to get out. Thankfully, I did manage to escape. Just!
But lesson learnt.

 tehmarks 07 Feb 2021
In reply to GCO:

> beware of difficulties escaping a simple bivvibag in a desperate hurry when you’ve been tossing and turning and somehow the zip and Velcro opening had migrated underneath you.

Similarly, though self-inflicted and more easily avoided: beware of difficulties escaping a tent when you're too drunk to find the zip and too incapable to find your headtorch.

And beware of going climbing with serving personnel.

 Robert Durran 07 Feb 2021
In reply to tehmarks:

> Hooped bivis are a fallacy in my view — they offer little of the weight advantages of a minimal bivi bag, and little of the advantages of a tent. They're a poor middle ground.

I pretty frequently bivi for a single night on a mountain top for photography reasons, often in places where I feel there is no guarantee I would get a tent up. I love it, but I find the main issue is condensation from breathing and from dew around the top of my sleeping bag (I don't really like the claustrophobic effect of having my head inside the bivi bag). I have been considering getting a hooped bivi to get around this problem. Would it do so? 

 JB 07 Feb 2021
In reply to GCO:

Bivvied out in NZ years back...as it got dark a number of possum appeared to investigate and make a nuisance of themselves. 

After a restless few hours I drifted off only to wake up in the middle of the night to become aware of something warm and hairy inside my bag...panicked for c. 30 seconds before I realized it wasn't a possum but rather my own arm which was pinned under my chest and had gone numb. 

 Rick Graham 07 Feb 2021
In reply to Robert Durran:

Yes, remember it well. Every breath causing more and more damp .

I think a hooped bivi would just spread the problem over all your bag not just the bit by your head, unless the breathabilty can cope. I doubt it especially in heavy rain.

The only time I have stayed dry in heavy rain is not breathing into the bag and with a small tarp to protect the head.

I now use a sleeping bag cover and either a small tarp or a home made  separate cowl.

NB none of these options is midge proof.

Post edited at 17:06
 tehmarks 07 Feb 2021
In reply to Robert Durran:

I can't say I speak from a position of great experience. Science would suggest that you've made the volume larger and thus reduced the relative humidity inside — but I'd be surprised if the air doesn't still end up fully saturated, at which point condensation will form I'd expect. It'll just take a bit longer.

 Robert Durran 07 Feb 2021
In reply to tehmarks:

> I can't say I speak from a position of great experience. Science would suggest that you've made the volume larger and thus reduced the relative humidity inside — but I'd be surprised if the air doesn't still end up fully saturated, at which point condensation will form I'd expect. It'll just take a bit longer.

But presumably the dew/frost situation will be improved. I'd be happy as long as there is not wet fabric in my face!

 tehmarks 07 Feb 2021
In reply to Robert Durran:

You need a woolly balaclava, laddie

Honestly? I wouldn't like to speculate. I assume you'll see immediate improvement from not having your sleeping bag in contact with the damp (dewy) ground, if I'm picturing what you mean correctly. I think Rick is probably correct though that you'll end up with a more evenly damp bag from condensation instead. Which may well be an improvement.

 damowilk 08 Feb 2021
In reply to JB:

My partner got freaked out on her first night Bivvying when a Kea landed on her bag, squawking it’s call. Her second attempt had her waking in a panic unable to find the zip to get out. There hasn’t been a third time to date! 

 Sean Kelly 08 Feb 2021
In reply to glenn0010:

I once witnessed a guy under a tarp near Glencoe and the midges were desperate. Tent every time but outside the midge season and in the relative dry a bivvy can be rewarding.

 Mudflap 08 Feb 2021
In reply to Robert Durran:

> I pretty frequently bivi for a single night on a mountain top for photography reasons, often in places where I feel there is no guarantee I would get a tent up. I love it, but I find the main issue is condensation from breathing and from dew around the top of my sleeping bag (I don't really like the claustrophobic effect of having my head inside the bivi bag). I have been considering getting a hooped bivi to get around this problem. Would it do so? 

Potentially yes.

I use a hooped goretex bivvi bag with a down sleeping bag. Ventilation and liveability are much improved over a hoopless bivvi bag. Condensation is not generally an issue. Never had dew around the top of the sleeping bag.

There's a storm flap around the hoop which enables the entrance zip to be left open a little and the bag to ventilate in any weather.

Great for a single night on a mountain with a fair weather forecast.

 Robert Durran 08 Feb 2021
In reply to Mudflap:

> I use a hooped goretex bivvi bag with a down sleeping bag. Ventilation and liveability are much improved over a hoopless bivvi bag. Condensation is not generally an issue. Never had dew around the top of the sleeping bag.

Thanks.

 ben b 08 Feb 2021
In reply to glenn0010:

Agree with almost all the above (including Ron Turnbull's niche but excellent Book of The Bivvy).

Unless there is a strong reason to bivvy (fab weather, nowhere to put up a tent) then a lightweight tent wins every time for me - better protection, midge/sandfly free, similar weight, less concern re damp sleeping bags. I totally relate to the damp sleeping bag opening issues and similarly dislike having damp goretex slapping me in the face. 

These days my 2 person, 3+ season, two layer, strong and spacious two vestibule tent is only 1.2kg, so I would likely get the 1P version of the same if I needed a 1 person tent - that's about 800g. https://durstongear.com/product/x-mid-1p - the thick Synmat would be fine in there. 

Have fun

b

 ben b 08 Feb 2021
In reply to the OP:

> damp goretex slapping me in the face. 

Perhaps I should register the domain goretexslappers.com - premium subscribers get extra benefits which I shall leave to your fevered imagination.

b

 Dave the Rave 08 Feb 2021
In reply to Mudflap:

I once bivied on the steps of a synagogue in London. I woke up with a heavy dew on me


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