VBL inside sleeping bag and light weight bivi

[Wallstein]

While doing some research for ultralight bivi systems I came across this on Western Mountaineering's website

 

 

Has anyone used a system like this before? At only 127g (4.5oz) and being able to double as an emergency bivi it looks like a cool option.

 

 

Adventure Medical Kits have some what similar products that might also be pretty good for really light bivi setups. Sol Thermal bivy

 

 

I'm thinking about pairing one of the above VB setups with the Mont-bell Spiral Down Hugger which weighs in at a mere 391g (13.8). For a total bivy weight of 499g (17.6oz). This seams like it would be pretty light and versatile system.

 

 

I've also considered using the Spiral Down Hugger as two man blanket system along with a Integral Designs Guide Tarp. This would total 830g (29oz) for a two man bivi.

 

 

 

Any other ultra light bivy system out there?

[layton]

Yo!

 

I've used both the Western Mountaineering and the Adv Medical Kit. The Adv Medical one rips easily and is a 1-2 time use deal. The WM one is much sturdier. I slept very warm in a 16 oz bag with that system in the winter.

 

The tarp on top will soak your sleeping bags, but a double bag with both people in a VBL would be the driest, lightest, and warmest option.

[layton]

also a couple hand warmers tossed in help

[Sol]

Interesting bivy options there Mikey. I was just talking to a patagonia bound friend about lightweight bivy systems and overall, the lack of available options that are out there. Really, where is the ideal two man bivy sack?? It's unfortunate that these systems aren't more profitable as i'm sure we'd see some cool products and innovation.

 

Just some thoughts:

 

MB Down Hugger: seems a waste to bring a full zip quilt style bag up a big alpine objective. It's just not an efficient heat design. I think you'd be much better off taking on 2 more ounces of weight (1 gu pack) and bring a Feathered friends Vireo. Sick bag that besides the fact that its down would seem to be ideal.

[genepires]

I thought feathered friends made a 2 man sleeping bag or bivy sack for a while. May have been a limited production for colin and his kind.

 

I had a friend in bellingham who made his own 2 man bivy with goretex.

Edited October 27, 2011 by genepires

[mattp]

Yup. Colin and "his kind" are bad people. FF woudn't want to be associated with them on any long term basis.

[Dannible]

I've used the Adventure Medical bivy a handful of times years ago and pretty much hated it. A few nights in particular I remember waking up drenched in sweat, but very cold, and having to wait out the rest of the night like that. On one long trip I stopped using it after a few days, so I must have decided that it was worse than nothing. I do sweat more than most people though, and it wasn't paired with a real bag, so maybe it would work fine for you.

 

When trying to be really light I now use a stupid 1 lb synthetic bag that I got for cheap along with a bivy sack or firstlight and rarely get a good night's sleep, so I can't help you. One of these nice light bags is going to be my next big purchase.

[Wallstein]

I've got a custom FF vireo with half zip that I've used a bunch. Its great if it is just me and no wind. Thats what I used on the Devils Thumb traverse. Its also been used as two man setup but its just to tight. Definitely a great bag.

 

But by adding a VBL from Western or the Sol Bivy and using the MB Down Hugger its only 50 grams more than a Vireo but I now have a wind/rain proof bivi.

 

Also like the option of being able to share the Down Hugger with a partner, which is a no go with the viero.

 

I've modified a BD winter bivi to barely fit two but it does very little to reduce the suffer factor. I just bought few yard of 1.3 oz Sil Nylon from Seattle Fabrics and am going to sew up a two man suffer sac.

 

 

 

 

 

 

This was after the first of two REALLY cold shiver bivis on Fitzroy. Some how the decision of bringing a sleeping bag never came up so we didn't bring one. You can see the BD winter bivi around Kate's legs still. The night on top was definitely the coldest night of my life.

 

 

A couple years earlier we brought a bag but only one bag for three people. I've got a custom zippered insert that gives it some room but it was still packed like sardines

 

 

And yes of course chemical heater pacs are a must.

[kurthicks]

FF told me this summer that they still make the "Spoonbill" if you ask for it. I'm planning on getting on this winter.

[Laughingman]

. I just bought few yard of 1.3 oz Sil Nylon from Seattle Fabrics and am going to sew up a two man suffer sac.

 

 

Your in luck a company named Oware sells two variations on the two person bivy (one with zippers one without) at 12oz it seems like a good deal.

 

 

 

Here is the link

 

oware

[Fromage]

Yup. Colin and "his kind" are bad people. FF woudn't want to be associated with them on any long term basis.

 

That's either a joke or you don't know what you're talking about. Hard to catch subtle humor on the interwebs.

[NotMessner]

Have you tried VBL clothing? I'm no expert, but it seems if you add your clothes over VBL clothing, they will not get wet, but if you wear any clothes inside a VBL bag, your clothes will get wet.

[JasonG]

Yo, Cheese Head, surely you jest. Moderators have a sense of humor too....

[NotMessner]

[postER # 1]:

“For all around use, VBL clothing (pants & jacket) has an edge over VBL sleeping bag liners, and a VBL suit would be more versatile.

1. VBL suit can be layered over with down insulating clothes when temps dip very low, but a VBL bag liner would get the insulating clothes wet.

2. VBL clothes can be used during the day to keep insulating layers dry in very cold weather when they are necessary. No concern about keeping effort down to prevent sweating profusely.

3. VBL suit tops and bottoms can be packed separately from each other for ease of storage.

The doomed Scott South Pole attempt saw the men actually having to lay their frozen sleeping bags flat on the man-hauled sledges. Then at night they had to force themselves into the frozen bags which gave them very little warmth retention. In the end they all died of hypothermia before making it back to their base.”

[postER # 2]:

“I agree with you 100%. A Vapor Barrier suit, IMO, is leaps and bounds better then a Vapor Barrier bag liner. The reasons you mentioned nail it right on. Point 1 and 2 are the reason why I switched from a liner to clothing. I also think that the clothing works better as it is closer to your skin. When using a vapor barrier to line your sleeping bag, there is much more space between your skin and the VB and I think (no real data to prove this) that this allows more moisture to build up...that's what I have found anyway. Just in case someone is wondering, I use a brawny rain suit that is seam sealed as VB clothing. One day, I'll make a Cuben version. (Is much moisture lost from the gaps between upper body and lower body, and the gaps at the wrists, neck and ankles?) That would definitely be a "pro" for the bag liner. My VB socks have a cinch cord, as does the hood on my jacket. The waist of the pants and jacket as well as the ankles of the pants have a tight elastic but obviously not air tight. My guess would be that some moisture escapes, but not enough to cause any real damage to your insulation. Maybe a one piece rain suit is the way to go?”

[postER # 3]:

“Stephenson Warmlight makes vapor barrier sleeping bags: http://warmlite.com/vapor-barrier. I think they're useful on extended trips at extreme cold temperatures.

I tried VB clothing - first just a garbage bag on top with arm and neck holes, then a long sleeved shirt and pants I made with VB fabric from Warmlite. I thought regular clothing kept just as warm for the same weight. But I was just doing trips of less than a week with low temperatures in the 20s F. The Warmlite link talks about an artic expedition where their sleeping bags gradually got more and more wet and got less and less warm. In that case a VB liner would be useful. Warmlite makes sleeping bags with VB liners. But, they're very heavy. And they advertise that you can sleep naked in them and stay warm. That doesn't seem useful to me.”

[postER # 4]:

“It's definitely VBL clothing over a base layer for me. I use the Sil-Nylon Brawny Gear rain jacket and pants (I bought almost the last that were made). They double as my rain gear. Rarely does it rain and freeze hard in the same night, so I haven't have to worry about wet rain gear inside my bag. Multipurpose is always good--if it works for you.

If I get too cold in the bag, I can wear my puffy jacket over the VBL layer. This isn't possible with a VBL bag. I certainly wouldn't want to wear down inside a VBL! If it warms up during the night, I have been known to remove the rain jacket and pants. I keep them handy, though, because that usually means it will be raining by morning.”

 

 

 

[NotMessner]

I wore RBH Designs' products on Everest

by Sean Burch

"I have had the opportunity to test handwear and footwear from some of the most popular clothing companies in the U.S. What a surprise to me that the company I chose to keep my hands and feet warm in the world's most harsh conditions was from a little company in West Hartford, Connecticut. RBH Designs simply outperforms their competition. This is why I wore their products on Everest, for my USA speed ascent of Aconcagua, and the North Pole marathon. Kudos to Nancy and Ryan for their creations."

“I was totally impressed with the shirt. Wow!!

I wore it against the skin and did not take it off for the entire 7 day trip in the Alaska range in mid-March (including sleeping at night). I only used two upper body layers the entire week. When moving it was the shirt alone. At a stop, for our training objectives, I added a small puff-ball insulated jacket over the shirt. I had great fun telling the others, as they were getting cool and adding layers (4th and 5th layers), that “Yes, I agree it is cold…I think I will add a second layer.”

They were dumbfounded that I was standing around in sub-zero temps with one layer on. Very impressive.

The Trigg Mitts were almost obnoxiously warm. I really could not wear them while moving. Too warm. I suspect they will prove to be good summit gloves for high altitude.

I leave again for Alaska in two weeks. It probably won’t be cold enough to use the shirt as much as I did in March. We’ll see.”

Take care,

Mike Gibbs

Rigging for Rescue, Ouray, CO

 

“On leaden-sky winter days when zero temperature Canadian air sweeps down from the arctic, across the great Lakes, into the frozen northeast and 50 mph gusts chill the pines of the Pocono Plateau, my RBH Designs' SiliLoft jacket is awesome. While my neighbors dress in multi-layers of insulated underwear, heavy fleeces and bulky outerwear, I don a light sweater and slide into my lightweight SiliLoft jacket and am as "warm as toast". It is almost weightless. You don't even know you are wearing it. Congratulations! Amazing technology." Stuart Thody, Pocono Mountains, Pennsylvania

 

[robpatterson5]

I'm a huge fan of my Bothy bag for emergency bivys - I have an A-frame shaped one from ID, about 13oz and could fit 3 in a pinch - often wondered about that and a small down quilt and a sitting/lying bivy (both people head to toe).

A huge fan of having something to get out of the wind with.

You dont find silinylon too sweaty/wet for a bivy sack?

(I turn my bothy bag inside out a few times in the night)

Edited November 1, 2011 by robpatterson5

[Blake]

Yo Mikey,

 

Scott and I had a single unzipped bivy bag and 2 (~30 degree 20oz) down bags for 5 nights on our pollone trip. Although we didn't have nights as cold as you guys on fitz, it was still chilly and windy and we slept really well and even felt rested after bivy on route. If I did it again i think the ideal setup for something like this which you are describing would be LINK TO SUCH A PRODUCT a basic ( zipperless) sheet of Cuben/cubic Fiber or Silnylon that could be thrown over both climbers. Maybe 7' x 7'? It would maybe just have grommets in the 4 corners, or better yet, just small dabs of seam grip with holes poked through (poor-mans ultralight grommets). Then I'd be a fan of 2 ultralight bags like the montbell 40degreee bag, which weigh about 15oz each, though perhaps a spoonbill equivalent, or a down blanket from western mtneering, would be better. Stick your feet and lower legs in your pack and sleep on the rope, and overall i think it produces a pretty good shelter/sleep system for not much more weight than a full nalgene.

 

I think overal its worth picking the brain of some accomplished long distance hikers for their setups, and checking sites like this one: www.zpacks.com

 

 

It seems like with a VBL inside the bag, your warm air cushion of feathers is going to suffer a lot more convective heat loss due to wind than with a layer on the outside, and of course when it rains, you are hosed.

[layton]

blake's got a good point about the heat loss. i didn't realize this was for an open bivy.

if you can't afford this option, i've used the tarp of a tent and also my betalight sil tarp and had both of us wrap up in it = 1 pound.

[Dane]

MIkey, couple of thoughts for you but please pardon me repeating what you likely already know.

VBLs work best when it is cold, used alone next to your skin in a bag.

A water proof bag (bivy bag of any sort) will get you wet but works well for "ventilated" protection from the elements when things are bad outside.

 

Any unventilated sack over a down bag and the bag will be toast in a short amount of time from moisture. Full Gortex or Event bivy bags or bag covers aren't bad just fragile.

 

These things (below) are really the sheet used in the right way, but they aren't comfortable, a tent or a great place to sleep. I don't care what the picture says And 12 1/2oz (my weigh) for a 2 man version.

 

 

http://brooks-range.com/UltraLite-Alpini-Shelter-200.html

 

I've use VBLs a lot and real bivy bags (like this) a lot.

 

Never used both together because they defeat the purpose as each works to keep you warm.

 

Synthetic bag, VBL line and a bivy bag will work but there are better (lighter and warmer) ways to deal with things generally.

 

I use a custom Vireo with a water proof outer and a removable VBL liner.

But if I need a VBL might as well take a warmer bag generally and or a 2.5# tent.

Bivy tents are a miserable way to climb but they will keep you going with little else besides a stove required.

Half bags were developed in part to keep the majority of the bag out of the sack so it would stay drier.

How dry you stay in the bag and your jacket fairs depends on the amount of ventilation the bivy bag has.

The more ventilation the colder the bag will be inside.

 

 

But one of these, a small stove and the clothes on your back would have likely kept you warm on Fitroy. The idea was proven long ago in the alps on every major north face and likely used on the first ascent of Fitroy.

[Jens]

I want one of those!

[Marko]

Sort of a bothy bag with tie-in pass-thrus, eh? Not as restful as laying down I imagine.

 

http://www.terra-nova.co.uk/Product_Type/Tents/Bivi__Bothy_Bags/Superlite_Bothy_2_Red.html?view=description

 

 

[layton]

should be called the glory hole

[Dane]

Sort of a bothy bag with tie-in pass-thrus, eh?

 

Just a little more sophisticated bothy with vents. As common as trash in the alps.

[Laughingman]

Then I'd be a fan of 2 ultralight bags like the montbell 40degreee bag, which weigh about 15oz each, though perhaps a spoonbill equivalent, or a down blanket from western mountaineering, would be better.

 

PHD (the british company) makes a down blanket weighing 13oz, looks like it may fit the bill for the intended purpose.

 

PHD blanket

 

They also make the "Minim Ultra Down Sleeping Bag" weighing in at a ultralight

345g (12oz)

 

(They make some super cool stuff)

 

 

 

[crackers]

A couple of thoughts...

 

silnylon would be probably be a bit lighter and a LOT more "affordadurable" than a cubic tech fiber for a cover type tarp application. The weights of CTF that are widely used in making tarps will get turned into holey TP in the alpine...or at least that's my experience.

 

If you're into the "little tent thing we can hide in", the Ortik offering is much nicer than Brooks range. http://www.rockexotica.com/ortik/tupek.html is a link to see the thing.

 

And FF is making spoonbills, and the rumor is that they've got ONE (1) unspoken for currently...but of course they won't really work with the bothy tenty thingys...

 

The MSR/Cascade Designs/Thermarest alpine quilt is rad and warm...but not light at all so never mind.

 

Good luck!