down or synthetic for trekking in uttaranchal/himachal/ladakh/sikkim/arunachal ?

rajnag · Jul 5th, 2008, 01:34

Hi All,
I am wondering whether to buy down or synthetic sleeping bag for north and north east india treks ?
Should i get one down for dry cold areas like ladakh and one synthetic for wet areas like lower elevations and north eastern states ?
What temperature ratings should I go for ? what temperatures ranges will need to be planned for for autumn and winter treks ?
TO All knowledgeable folks : please put in your two cents.

bruce · Jul 5th, 2008, 04:17

I say it is a waste to get two bags for the same temperature. Since you will encounter wet weather in most above places, get a synthetic. A synthetic will do just fine in dry areas such as ladakh, it is just slightly heavier and less compressible. For 3 seasons a -10 degrees(+- a few) should be good and you can get warmer by adding a liner or putting on more clothes while you sleep.

Winter (and late autumn and early spring) is a different story. In high elevations it will be bitterly cold and any precipitation will be in form of dry snow so you don't have to worry too much about getting your down bag wet. Most people who climb in higher elevations go for at least a -30 degree down bag. Again you can add a liner or a vapor barrier liner to your bag to keep warmer.

Just my 2 cents!

rajnag · Jul 5th, 2008, 21:24

Bruce,
Thanks for your advice ! I was planning on doing treks both lower and higher altitude. I was looking at Nol's equipment list and basing myself off that.
http://www.nols.edu/courses/location...himalaya.shtml

I do not want to get a -30 degree bag simply because I do not plan to scale peaks. Just trek high altitude passes and such. After all the required acclimatization etc of course.
Also I cannot use such a bag anywhere else.
Down lasts a lot longer than synthetics do.
I was reading some scientific studies done and the gist of it is that after a few compression cycles, synth's loose about 30 % of their loft and stabilise. So a -20 bag will be comfortable probably around 0 to -5 and after loosing loft etc might be comfortable only to 15-20 degrees F aka 3 season camping weather.

Now maybe I need to get an exclusively cold weather bag -20 degree down, atleast with a 1 kg of down in them.
I am basing this off some good trekking agencies that state their equipment requirements.
http://www.project-himalaya.com/jtre...ar-winter.html
http://www.project-himalaya.com/trek...ploratory.html

bruce · Jul 6th, 2008, 04:23

I just realized you are in NY. To be clear, I was convering bag ratings to centigrade. So I was recommending a 20F synthetic bag for 3 seasons.

I agree with you about the -30 bag. But if you want to do winter trekking in high altitude I think you will need something like that. I don't think you can find one bag that does it all. Another option is to get the "reactor" sleeping bag liner that is basically fleece and adds like 15 degrees to your bag(or similar products).

People are different in what they need in a sleeping bag. Some people sleep cold and some sleep warm. Also the whole bag rating is notoriously unreliable since there are no standards governing them. I picked up a 20 degree synthetic last year and I was choking in it after an hour in a 27F night. I had to strip down to a short sleeve and fully unzip the tent door to get some cold air in. And I am not a warm sleeper.

If you have some time to decide, you might want to rent a few sleeping bags from REI and test them in cold weather to get an idea of what you need. Nothing like experience to help you figure out what to buy.

Good luck

kmalik · Jul 6th, 2008, 04:58

I'd say synthetic. Down, depending upon the bird donating the feather, can be warmer. However, it does not mix well with water - and with exception of Ladakh, other areas you mention might have rain. Also, while down lasts longer, it does lose warmth as feathers get compressed and the amount of air trapped (that leads to its superior warmth) goes down. In comforters, you can have the feather cleaned and fluffed to restore the warmth (only makes sense if you have high-quality down comforter) - but I haven't seen people do that often. My guess is synthetics might hold on to their insulating power better.

Larsuld · Jul 6th, 2008, 14:38

Quote:

Originally Posted by bruce

Also the whole bag rating is notoriously unreliable since there are no standards governing them.

There are attempts at introducing common standards, though I wouldn't be able to say much about them, because the standards organizations seem to want to finance themselves by selling their documents at rates above the reservation prices of most consumers, me at least. (Or am I just poor at googling!?:-))

There is ISO 11079 (last update 2007) - "Ergonomics of the thermal environment"
and
EN 13537:2002 "Requirements for Sleeping Bags"
Which is a common European standard for laboratory tests, which specifies a separate 'comfort temperature range' for men and women and an extreme temperature which is defined as avoiding hypothermia in a couple of hours. (I know you're in U.S). These days in Denmark, almost all sleeping bags conform to this latter standard, or claim they do anyway. I'm not sure if it's compulsory or not. But a few years back there were no references to standards on the bags.

You're right in your objections as to the large variability in our night time temperature preferences, but I believe a standard is certainly better than each manufacturer more or less claiming whatever they feel like. Perhaps we will be a bit better off if each of us is able to 'calibrate' our own experience to the standard... so maybe the second sleeping bag we buy will have the right temperature range.

Last little thing. Sleeping bag prices have really plummeted in Denmark. A lot of 'discount' sleeping bags by lesser known manufacturers which seem to score quite well on the standards tests have appeared in warehouses and supermarkets. Perhaps the standardization will remove some of the monopoly power of the large brand names. I just got myself a synthetic filled sleeping bag with an alleged comfort range between 13 deg to -6 deg C (55 to 21 deg F) to and extreme temperature -23 deg. (-9F) for just 70 US$. The weight is only 1,9 kg. That's extremely cheap for Danish conditions, and I've even seen similar bags for sale for just 30US$. A few years back this would have been 150-200US$ minimum.

Well, stay warm and sleep tight

Lars

ashutosh69 · Jul 6th, 2008, 17:32

1. If you are gunning for treks in the range of 15000 till 20000, there are areas you can go to in early summer and late autumn. These are periods when precipitations arent that pronounced. These are also places and times when early morning temps dip as low as -25 deg C (I have experienced that more than once). My down jacket and sleeping bag have been faithful even in bivouac camps in high passes in mid november

2. If one is attempting some of the higher reaches in monsoons (as is recommended for many destinations) I would rather prepare well with water proof liners and covers.

3. To maintain the fluff and warmth of the feathers one needs to be careful on storage and packing of such material.. for example you never roll a down bag while packing...you just stuff it in randomly

However, if there are synthetics that match the thermal properties and yet are hydrophobic and are light on the wallet, why not??

rajnag · Jul 6th, 2008, 22:47

Thanks ashutosh for that clarifications. It was nice talking to you on the phone as well.
Here are a few links that talk about insulating materials in a more empirical manner.
http://www.backpackinglight.com/cgi-...378/index.html

great site for High altitude stuff:
http://www.psychovertical.com/?gear

Other threads that are very useful; they compare various jackets/sleepin bags and estimate the warmth.
http://www.backpackinglight.com/cgi-...=94914 #94914
http://www.backpackinglight.com/cgi-...=99184 #99184
http://www.backpackinglight.com/cgi-...0138 1#101381
http://www.backpackinglight.com/cgi-...=90389 #90389

http://www.backpackinglight.com/cgi-...=96186 #96186
http://www.backpackinglight.com/cgi-...=86824 #86824
http://www.backpackinglight.com/cgi-...=75054 #75054
http://www.backpackinglight.com/cgi-...=74290 #74290
http://www.backpackinglight.com/cgi-...=74014 #74014

This person is an acknowledged expert in such things and I follow his postings avidly:
http://www.backpackinglight.com/cgi-...l?u=richard295

Highly thought of manufacturers:
western mountaineering
feathered friends
mont-bell
patagonia
integral designs
mountain hardware
wild things
bozeman stoveworks aka BPL's ultralight stuff
Rab
Arc'teryx
REI
MEC
and some others that I don't remember.

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Jul 5th, 2008, 01:34	#1
rajnag Member Join Date: Jan 2007 Location: NY Posts: 75	down or synthetic for trekking in uttaranchal/himachal/ladakh/sikkim/arunachal ? Hi All, I am wondering whether to buy down or synthetic sleeping bag for north and north east india treks ? Should i get one down for dry cold areas like ladakh and one synthetic for wet areas like lower elevations and north eastern states ? What temperature ratings should I go for ? what temperatures ranges will need to be planned for for autumn and winter treks ? TO All knowledgeable folks : please put in your two cents.

Jul 5th, 2008, 04:17	#2
bruce Member Join Date: Sep 2007 Location: USA Posts: 32	I say it is a waste to get two bags for the same temperature. Since you will encounter wet weather in most above places, get a synthetic. A synthetic will do just fine in dry areas such as ladakh, it is just slightly heavier and less compressible. For 3 seasons a -10 degrees(+- a few) should be good and you can get warmer by adding a liner or putting on more clothes while you sleep. Winter (and late autumn and early spring) is a different story. In high elevations it will be bitterly cold and any precipitation will be in form of dry snow so you don't have to worry too much about getting your down bag wet. Most people who climb in higher elevations go for at least a -30 degree down bag. Again you can add a liner or a vapor barrier liner to your bag to keep warmer. Just my 2 cents!

Jul 5th, 2008, 21:24	#3
rajnag Member Join Date: Jan 2007 Location: NY Posts: 75	Bruce, Thanks for your advice ! I was planning on doing treks both lower and higher altitude. I was looking at Nol's equipment list and basing myself off that. http://www.nols.edu/courses/location...himalaya.shtml I do not want to get a -30 degree bag simply because I do not plan to scale peaks. Just trek high altitude passes and such. After all the required acclimatization etc of course. Also I cannot use such a bag anywhere else. Down lasts a lot longer than synthetics do. I was reading some scientific studies done and the gist of it is that after a few compression cycles, synth's loose about 30 % of their loft and stabilise. So a -20 bag will be comfortable probably around 0 to -5 and after loosing loft etc might be comfortable only to 15-20 degrees F aka 3 season camping weather. Now maybe I need to get an exclusively cold weather bag -20 degree down, atleast with a 1 kg of down in them. I am basing this off some good trekking agencies that state their equipment requirements. http://www.project-himalaya.com/jtre...ar-winter.html http://www.project-himalaya.com/trek...ploratory.html

Jul 6th, 2008, 04:23	#4
bruce Member Join Date: Sep 2007 Location: USA Posts: 32	I just realized you are in NY. To be clear, I was convering bag ratings to centigrade. So I was recommending a 20F synthetic bag for 3 seasons. I agree with you about the -30 bag. But if you want to do winter trekking in high altitude I think you will need something like that. I don't think you can find one bag that does it all. Another option is to get the "reactor" sleeping bag liner that is basically fleece and adds like 15 degrees to your bag(or similar products). People are different in what they need in a sleeping bag. Some people sleep cold and some sleep warm. Also the whole bag rating is notoriously unreliable since there are no standards governing them. I picked up a 20 degree synthetic last year and I was choking in it after an hour in a 27F night. I had to strip down to a short sleeve and fully unzip the tent door to get some cold air in. And I am not a warm sleeper. If you have some time to decide, you might want to rent a few sleeping bags from REI and test them in cold weather to get an idea of what you need. Nothing like experience to help you figure out what to buy. Good luck

Jul 6th, 2008, 04:58	#5
kmalik Senior Member Join Date: Dec 2006 Location: Ohio Posts: 446	I'd say synthetic. Down, depending upon the bird donating the feather, can be warmer. However, it does not mix well with water - and with exception of Ladakh, other areas you mention might have rain. Also, while down lasts longer, it does lose warmth as feathers get compressed and the amount of air trapped (that leads to its superior warmth) goes down. In comforters, you can have the feather cleaned and fluffed to restore the warmth (only makes sense if you have high-quality down comforter) - but I haven't seen people do that often. My guess is synthetics might hold on to their insulating power better.

Jul 6th, 2008, 17:32	#7
ashutosh69 Senior Member Join Date: Nov 2007 Location: Delhi Posts: 121	another half cent for a Down Bag for Very High Alti 1. If you are gunning for treks in the range of 15000 till 20000, there are areas you can go to in early summer and late autumn. These are periods when precipitations arent that pronounced. These are also places and times when early morning temps dip as low as -25 deg C (I have experienced that more than once). My down jacket and sleeping bag have been faithful even in bivouac camps in high passes in mid november 2. If one is attempting some of the higher reaches in monsoons (as is recommended for many destinations) I would rather prepare well with water proof liners and covers. 3. To maintain the fluff and warmth of the feathers one needs to be careful on storage and packing of such material.. for example you never roll a down bag while packing...you just stuff it in randomly However, if there are synthetics that match the thermal properties and yet are hydrophobic and are light on the wallet, why not??

Jul 6th, 2008, 22:47	#8
rajnag Member Join Date: Jan 2007 Location: NY Posts: 75	Thanks ashutosh for that clarifications. It was nice talking to you on the phone as well. Here are a few links that talk about insulating materials in a more empirical manner. http://www.backpackinglight.com/cgi-...378/index.html great site for High altitude stuff: http://www.psychovertical.com/?gear Other threads that are very useful; they compare various jackets/sleepin bags and estimate the warmth. http://www.backpackinglight.com/cgi-...=94914 #94914 http://www.backpackinglight.com/cgi-...=99184 #99184 http://www.backpackinglight.com/cgi-...0138 1#101381 http://www.backpackinglight.com/cgi-...=90389 #90389 http://www.backpackinglight.com/cgi-...=96186 #96186 http://www.backpackinglight.com/cgi-...=86824 #86824 http://www.backpackinglight.com/cgi-...=75054 #75054 http://www.backpackinglight.com/cgi-...=74290 #74290 http://www.backpackinglight.com/cgi-...=74014 #74014 This person is an acknowledged expert in such things and I follow his postings avidly: http://www.backpackinglight.com/cgi-...l?u=richard295 Highly thought of manufacturers: western mountaineering feathered friends mont-bell patagonia integral designs mountain hardware wild things bozeman stoveworks aka BPL's ultralight stuff Rab Arc'teryx REI MEC and some others that I don't remember.

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