It needs to be:


Lightweight

Breathable (Gtx, Event)

Waterproof on bottom

Durable

Mosquito net

Roomy enough to get me in and basic gear.



I already came across this one:

http://www.rab.uk.com/equipment/bivvis/ ... extra_long)---62/

Looks interesting, any other suggestions?

Integral Designs makes very good bivy bags. I've got Salathe, it might not be the lightest one out there, but is absolutely weather-proof and has all the other features you mentioned. The only con: difficult to get in Europe (but is possible).

Get one with eVent, you will be VERY glad you did. It breathes much better than gore tex at lower internal humidity levels, which is very important for a bivy sack.

I have a OR Basic Bivy. It's sort of like the Alpine and Advanced but with no pole. When it is zipped up, you feel like you're seeping in a body bag.

Also, which is annoying, the zipper is only across the front part of the bag, so you have to shimmy into the thing and slide back out on the snow, or wet ground...

How about one that weighs 6 ounces?

http://www.titaniumgoat.com/Bivy.html

Hunka -- £ 33.00 (€ 37.20, $ 53.29)
A simple but waterproof and breathable bivy cover for lightweight camping.

Hunka regular
* Weight: 388g (average of 10 bags)
* Hydrostatic head 10,000mm
* MVP of 10,000g/m2/24hr
* Pack size: 15cm sphere
* Length: 215cm
* Width: 80cm


Waterproof
Yes, the fabric has a hydrostatic head of 10,000mm, basically like your tents groundsheet

Breathable
Yes, the fabric has a moisture vapour permeability (MVP) of 10,000g/m2/24hr

Low weight and bulk
We weighed 10 and the average was 388g

Integral stuff pocket
On the base of the bag is a mesh bag that you stuff the bivvy bag into, so no stuffsack to lose

Dual drawcord
You can close from either side or both so suitable for left and right handers and if you sleep on your front as I do then no toggle to press into your chest bone

Hooded design
Although lighter, some of the more basic bivi bags don't offer quite the same usabilty. The hood design allows you to overlap the opening making it more weather proof, however this design only has a drawcord so in heavy and direct rain you may get wet. The shaped hood is also good in snowy bivis where loose snow tries to get in your bag all the time

FortMental wrote:I use a BD Lighthouse. About 3 lbs. and (barely) big enough for me and winter gear (and you can cook inside!). A bivy sack is good for places where nothing else will fit and where tents are not allowed.

My bivy sack is lighter than your tent. Building a snow cave is lighter than your tent.




BUT.... A tent is more comfortable than my bivy sack.

catullus wrote:How about one that weighs 6 ounces?

http://www.titaniumgoat.com/Bivy.html

And probably has the durability of a heavy garbage sack.


Plus, I have heard that those TiGoat sacks are not really all that weather proof, and in a downpour they leak.

FortMental wrote:

OJ Loenneker wrote:

FortMental wrote:I use a BD Lighthouse. About 3 lbs. and (barely) big enough for me and winter gear (and you can cook inside!). A bivy sack is good for places where nothing else will fit and where tents are not allowed.

My bivy sack is lighter than your tent. Building a snow cave is lighter than your tent.

BUT.... A tent is more comfortable than my bivy sack.

...and dryer than your cave. Maybe. OK, not always. But it's less work. Definitely less work.

And a decently made cave is a LOT more sturdy than a Lighthouse when the weather gets bad. And warmer.

mconnell wrote:
And a decently made cave is a LOT more sturdy than a Lighthouse when the weather gets bad. And warmer.

I've never dug a snow cave without getting totally soaked with sweat in the process. I basically had to carry a separate set of clothes for digging.

OJ Loenneker wrote:

catullus wrote:How about one that weighs 6 ounces?

http://www.titaniumgoat.com/Bivy.html

And probably has the durability of a heavy garbage sack.


Plus, I have heard that those TiGoat sacks are not really all that weather proof, and in a downpour they leak.

I have one of these. Sure, it's not the most weatherproof bivy sack out there, but it doesn't get totally soaked inside during a downpour. Best used while also hiding under a rock:

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Get a firstlight, and a cheap bivy. You'll use the firstlight more often, and the bivy when you plan to.

Bivy sacks are really not that comfortable. Here is the bivy I went with....

http://www.prolitegear.com/rab_ultra_bivy.html

6.7 oz. Welded seams... does the trick when I need it. I mostly take it on summer stuff, when I am trying to keep the weight down.

I just bought an OR Alpine Bivy. I used my friend's on Rainier last year and wanted my own. It's completely waterproof, has a single pole to keep fabric off your head, and has mosquito netting. Pretty much the perfect bivy, in my opinion.

The Integral Designs Unishelter has worked well for me.