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I'm sure there must be loads of info about this, but I tried a quick google and forum search to no avail.
Honestly, (ie not catalogue hype) how much warmer does a silk liner make a sleeping bag?
The bag is a rab quantum 400, in case it helps.
Cheers, ally
Honestly, (ie not catalogue hype) how much warmer does a silk liner make a sleeping bag?
The bag is a rab quantum 400, in case it helps.
Cheers, ally
In reply to Alasdair Fulton: It is said it adds upto a season onto your bag...
I really feel the cold and the addition of a silk liner makes me toasty warm
I really feel the cold and the addition of a silk liner makes me toasty warm
In reply to Alasdair Fulton:
It depends. Really it just reduces the volume of air you have to heat, though it will have some warmth value in itself.
It'll boost it a bit.
I know that doesn't seem much help but folks opinions will vary from 'adds a season' to 'does nowt' with very little more than personal experience (at best) or second hand/hearsay.
It depends. Really it just reduces the volume of air you have to heat, though it will have some warmth value in itself.
It'll boost it a bit.
I know that doesn't seem much help but folks opinions will vary from 'adds a season' to 'does nowt' with very little more than personal experience (at best) or second hand/hearsay.
In reply to Alasdair Fulton:
can't say I really notice that much difference in terms of warmth, but for keeping the bag clean and smell-free they're great. Far easier washing the liner than the bag...
can't say I really notice that much difference in terms of warmth, but for keeping the bag clean and smell-free they're great. Far easier washing the liner than the bag...
In reply to Alasdair Fulton:
As you can see, no definitive scientific answer. But just get one. One of my favourite bits of kit.
As you can see, no definitive scientific answer. But just get one. One of my favourite bits of kit.
1
In reply to Alasdair Fulton: Regardless of the (slight) extra warmth, it's worth it purely in terms of not needing to wash your sleeping bag very much.
So, to sum up, most actual users say there's not a great deal of warmth gain, however most non-users follow the myth of +1 season.
I got my bag on discount (£185), but am now wishing I maybe got the 600, as i'm planning to use it in scotland this winter.
I started another thread about this the other day but,
I've got a 2 season (Barely 2 season) snugpack softie 3 and any camping I do this winter I think i should be able to cope with carrying the extra 800grammes, but will it be worth it insulation-wise? (3 season bag inside 2 season)
The rab is rated at -5c (i know the ratings are only guides) but how much colder will be comfortable (roughly) using the 2 season over the rab bag?
Cheers, ally.
I got my bag on discount (£185), but am now wishing I maybe got the 600, as i'm planning to use it in scotland this winter.
I started another thread about this the other day but,
I've got a 2 season (Barely 2 season) snugpack softie 3 and any camping I do this winter I think i should be able to cope with carrying the extra 800grammes, but will it be worth it insulation-wise? (3 season bag inside 2 season)
The rab is rated at -5c (i know the ratings are only guides) but how much colder will be comfortable (roughly) using the 2 season over the rab bag?
Cheers, ally.
In reply to Alasdair Fulton: I have used a Softie 9 inside an army sleeping bag, in a Canadian winter, in the Rockies. It was super warm, the combo was huge and wieght & volume ment it was no use hiking far from the car. My advise would be try it in bad conditions where a quick exit is handy.
Cheers Dave
Cheers Dave
In reply to Alasdair Fulton:
I find it makes my sleeping bag a bit warmer but I get myself all tangled up in it when I'm asleep so it only gets used if it's likely to be very cold. .
I find it makes my sleeping bag a bit warmer but I get myself all tangled up in it when I'm asleep so it only gets used if it's likely to be very cold. .
In reply to Alasdair Fulton:
The other thing you can try is something like a Meraklon liner - definitely adds an extra season in my experience. A quick google brings em up at £20-30 so its even cheaper than silk ...
The other thing you can try is something like a Meraklon liner - definitely adds an extra season in my experience. A quick google brings em up at £20-30 so its even cheaper than silk ...
In reply to Alasdair Fulton:
I can't say that I notice much differenc in my bag but then it is warm as toast anyway. Of course the other reason for a liner is that it is a lot easier to clean than the bag itself.
I can't say that I notice much differenc in my bag but then it is warm as toast anyway. Of course the other reason for a liner is that it is a lot easier to clean than the bag itself.
In reply to marie:
I knew a Scotsman who came in tartan, but a story for another audience
> (In reply to Kenny) They come in pretty colours too.
>
>
I knew a Scotsman who came in tartan, but a story for another audience
In reply to Alasdair Fulton: Seems to improve the bag rating by about 10 degC compared to none at all and about 5 deg C compared to a microfleece one.
In reply to Horse:
ANother reason, not THE other reason. I actually use mine a lot more as a sort of indoors sleeping bag / easily portable sheet, than I do as an actual liner. They pack down so small, you can just stick them in the bottom of your camera bag or whatever and if you end up staying over at a mate's, they don't have to rustle up a skanky old blanket and you don't have to sleep in your clothes to avoid skanking up their sofa or whatever.
> (In reply to Alasdair Fulton)
>
Of course the other reason for a liner is that it is a lot easier to clean than the bag itself.
>
ANother reason, not THE other reason. I actually use mine a lot more as a sort of indoors sleeping bag / easily portable sheet, than I do as an actual liner. They pack down so small, you can just stick them in the bottom of your camera bag or whatever and if you end up staying over at a mate's, they don't have to rustle up a skanky old blanket and you don't have to sleep in your clothes to avoid skanking up their sofa or whatever.
In reply to Alasdair Fulton: over several years i have tried silk,micro fleece,merkalon liners.in my opinion they dont make your bag any warmer at all in fact i find they might even make you colder,or feel colder at least,the only conclusion i can come to why this happens at least to me is that you are heating up the liner not the bag,now ok its all extra insulation so you should feel warmer but maybe its the feel of a warm liner against you rather than a warm thick bag,i havent used one for ages and in fact i feel warmer the less i wear in my bag aswell,hope this helps although it probrably wont!....cliff
In reply to Alasdair Fulton:
A bit off the topic but how durable and washable is silk? I want a sheet slpng bag for travelling with and am thinking of getting a silk one but i will be using it a lot on its own, possibly on floors and manky matresses, so it needs to be tough and easily washable. most of the ones i've seen are white (which doesn't help the dirtiness) and i hear silk's a pain to take care of and catches on stuff easily so it get loops etc. is this right?
Which one wld you reccd getting? I like the look of the Rab Endura big square heavy duty one but it seems a bit pricey (£45+). I'd prefer a square, not mummy-/sleeping bag-shaped one as i probly won't be using it as a liner. Ta.
A bit off the topic but how durable and washable is silk? I want a sheet slpng bag for travelling with and am thinking of getting a silk one but i will be using it a lot on its own, possibly on floors and manky matresses, so it needs to be tough and easily washable. most of the ones i've seen are white (which doesn't help the dirtiness) and i hear silk's a pain to take care of and catches on stuff easily so it get loops etc. is this right?
Which one wld you reccd getting? I like the look of the Rab Endura big square heavy duty one but it seems a bit pricey (£45+). I'd prefer a square, not mummy-/sleeping bag-shaped one as i probly won't be using it as a liner. Ta.
In reply to Judderman:
The silk ones also come in black, although a black silk sb liner always feels slightly "Penthouse" for some unexplainable reason.
OK on manky matresses but probably don't stand up to bothy floors too well (but then what does?)
I think mine is by a company called Tea-Tree or something like that (that could be a complete figment of my imagination), I think it's British made as it has a little Union Jack on the stuff bag. I seem to remember buying it in Slush and Rubble at some extortionate price about 4 years ago - it's still going strong though and gets used all the time. It's pretty lightweight, stuffs down to a tennis ball size.
The silk ones also come in black, although a black silk sb liner always feels slightly "Penthouse" for some unexplainable reason.
OK on manky matresses but probably don't stand up to bothy floors too well (but then what does?)
I think mine is by a company called Tea-Tree or something like that (that could be a complete figment of my imagination), I think it's British made as it has a little Union Jack on the stuff bag. I seem to remember buying it in Slush and Rubble at some extortionate price about 4 years ago - it's still going strong though and gets used all the time. It's pretty lightweight, stuffs down to a tennis ball size.
In reply to Judderman:
Don't buy Rab silk liners. They're not made by Rab. They're made by http://www.jagbags.co.nz who will sell directly to you at a much cheaper price. The prices on the site include p&p to the UK too.
Don't buy Rab silk liners. They're not made by Rab. They're made by http://www.jagbags.co.nz who will sell directly to you at a much cheaper price. The prices on the site include p&p to the UK too.
In reply to Alasdair Fulton:
my pig fur liner raised the ambient temperature within my doss bag by 0.884 degrees C.
Save money - pull a skinny bird
my pig fur liner raised the ambient temperature within my doss bag by 0.884 degrees C.
Save money - pull a skinny bird
In reply to Nevis-the-cat: Now there's an idea, take the girlfriend along as a mini-heater, doubt she'll go though, no shops nearby ;@)
In reply to Alasdair Fulton:
mine is presnetly en route to Slush and Rubble to buy yet another tent.....
The Imelda Marcos of the tent world that one.
mine is presnetly en route to Slush and Rubble to buy yet another tent.....
The Imelda Marcos of the tent world that one.
In reply to Jiffy:
you know that for a fact?
> (In reply to Judderman)
>
> Don't buy Rab silk liners. They're not made by Rab. They're made by http://www.jagbags.co.nz
>
> Don't buy Rab silk liners. They're not made by Rab. They're made by http://www.jagbags.co.nz
you know that for a fact?
In reply to Alasdair Fulton: not just the warmth factor, also think of using one as helping your bag stay fresher for longer as you can wash the silk liner easily and will stop your bag from stinking.
i went to a company in nz - quick delivery and much cheaper than shops here. get one.
i went to a company in nz - quick delivery and much cheaper than shops here. get one.
In reply to Nevis-the-cat:
You must pull some right mingers if they work out cheaper than a silk liner
> Save money - pull a skinny bird
You must pull some right mingers if they work out cheaper than a silk liner
In reply to epik:
Yep, my 'Rab' silk liner came with a big Jagbags label stitched to it! I was a bit annoyed since I'd paid extra for the Rab one thinking it would be superior.
Yep, my 'Rab' silk liner came with a big Jagbags label stitched to it! I was a bit annoyed since I'd paid extra for the Rab one thinking it would be superior.
In reply to Alasdair Fulton:
Alasdair - a liner is a great thing, mostly to keep your bag clean. As for warmth, I objectively feel a bit warmer in mine. You get a tad more insulation and an extra thingimy to stop cold drafts and air moving inside your bag. But if you're really concerned about being chilly in your bag throw in an extra base layer, that way the insulation you're carrying goes exactly where it is needed. And ignore the zillion posts that are sure to follow about how it's warmer to sleep with nothing on inside your bag - there is no science and very faulty logic behind that. Also drape your belay jacket over the top of your bag and pack some warm socks (or little booties) and a hat - between these you can easily add a sesaon to a bag.
Alasdair - a liner is a great thing, mostly to keep your bag clean. As for warmth, I objectively feel a bit warmer in mine. You get a tad more insulation and an extra thingimy to stop cold drafts and air moving inside your bag. But if you're really concerned about being chilly in your bag throw in an extra base layer, that way the insulation you're carrying goes exactly where it is needed. And ignore the zillion posts that are sure to follow about how it's warmer to sleep with nothing on inside your bag - there is no science and very faulty logic behind that. Also drape your belay jacket over the top of your bag and pack some warm socks (or little booties) and a hat - between these you can easily add a sesaon to a bag.
In reply to epik:
It's true. They have the Jagbag labels.
> (In reply to Jiffy)
> [...]
>
> you know that for a fact?
> [...]
>
> you know that for a fact?
It's true. They have the Jagbag labels.
In reply to Dave Hunter, Rock + Run:
what current ones? as in ones made since Rab was taken over? not questioning it just curious!
> (In reply to epik)
> [...]
>
>
> It's true. They have the Jagbag labels.
> [...]
>
>
> It's true. They have the Jagbag labels.
what current ones? as in ones made since Rab was taken over? not questioning it just curious!
In reply to Jiffy:
you'd think someone would have the idea of atleast re-labelling them
> (In reply to epik)
>
> Yep, my 'Rab' silk liner came with a big Jagbags label stitched to it! I was a bit annoyed since I'd paid extra for the Rab one thinking it would be superior.
>
> Yep, my 'Rab' silk liner came with a big Jagbags label stitched to it! I was a bit annoyed since I'd paid extra for the Rab one thinking it would be superior.
you'd think someone would have the idea of atleast re-labelling them
In reply to papajon:
post 1 of zillions!
why is it very faulty logic?
Your sleeping bag is a better insulator than your clothes. Your clothes insulate the individual part of the body they cover. As you get cold your body removes blood circulation from the extremities making them cold. Other parts of your body produce/let off more heat than your extremities so it makes sense to allow that heat to warm the sleeping bag as a whole in order to keep your extremities warmer. sleeping naked in a good sleeping bag will keep you warm and feeling warm as all parts of your bady are kept at a comfortable level. It is not a case of naked is warmer as your core body temp will be higher with clothes but naked you will feel warmer and in extreme situations the chances of frostbite will be less though obviously in extreme situations comfort might be substituted for a hihger core temp.
Personally i find if i wear clothes my feet will always be cold, if im naked i always end up having to stick my feet out of bag as they are too hot!
> And ignore the zillion posts that are sure to follow about how it's warmer to sleep with nothing on inside your bag - there is no science and very faulty logic behind that.
post 1 of zillions!
why is it very faulty logic?
Your sleeping bag is a better insulator than your clothes. Your clothes insulate the individual part of the body they cover. As you get cold your body removes blood circulation from the extremities making them cold. Other parts of your body produce/let off more heat than your extremities so it makes sense to allow that heat to warm the sleeping bag as a whole in order to keep your extremities warmer. sleeping naked in a good sleeping bag will keep you warm and feeling warm as all parts of your bady are kept at a comfortable level. It is not a case of naked is warmer as your core body temp will be higher with clothes but naked you will feel warmer and in extreme situations the chances of frostbite will be less though obviously in extreme situations comfort might be substituted for a hihger core temp.
Personally i find if i wear clothes my feet will always be cold, if im naked i always end up having to stick my feet out of bag as they are too hot!
In reply to epik:
Yay - an argument! (I'm not really a troll, promise)
You make a good point, and I've noticed that it often seems warmer to sleep naked in a bag. But insulation is cumulative, so adding a sleeping bag to the outside of yourself is like adding a super-duper additional layer on top of whatever you already have. Admittedly, as you point out, your feet will shed warmth faster than the rest of you.
But there are two ways to share the heat from the rest of your body with your slowly freezing toes.
The one way that you suggest is to strip down inside your bag and warm all the air in the bag, thus warming your toes. The problem with that is if it's cold enough, and your bag isn't well insulated enough then you can't keep adding heat to the bag fast enough to offset the heat that's being lost to the outside world.
The other way is to share the heat internally - by keeping your core body temperature high enough that it doesn't shut down the flow to the extremities. I saw a telly show once where they put an electric vest on some chaps and then sent them to a freezer and measured how long it took their ungloved hands to cool. They were able to sit there very happily with warm hands so long as heat was applied to their chests and sholders. The control group was a bunch of people without the extra warmth being applied and their hands froze pretty quickly, even where they were given gloves. The lesson is that a warm core keeps your body shunting warm blood to the extremities, and the best way to keep your core warm is to slow heat loss.
As an aside, I now keep a pair of booties on cold trips, and they seem to help stop my toes chilling faster than the rest of me (and I sleep pretty cold).
Yay - an argument! (I'm not really a troll, promise)
You make a good point, and I've noticed that it often seems warmer to sleep naked in a bag. But insulation is cumulative, so adding a sleeping bag to the outside of yourself is like adding a super-duper additional layer on top of whatever you already have. Admittedly, as you point out, your feet will shed warmth faster than the rest of you.
But there are two ways to share the heat from the rest of your body with your slowly freezing toes.
The one way that you suggest is to strip down inside your bag and warm all the air in the bag, thus warming your toes. The problem with that is if it's cold enough, and your bag isn't well insulated enough then you can't keep adding heat to the bag fast enough to offset the heat that's being lost to the outside world.
The other way is to share the heat internally - by keeping your core body temperature high enough that it doesn't shut down the flow to the extremities. I saw a telly show once where they put an electric vest on some chaps and then sent them to a freezer and measured how long it took their ungloved hands to cool. They were able to sit there very happily with warm hands so long as heat was applied to their chests and sholders. The control group was a bunch of people without the extra warmth being applied and their hands froze pretty quickly, even where they were given gloves. The lesson is that a warm core keeps your body shunting warm blood to the extremities, and the best way to keep your core warm is to slow heat loss.
As an aside, I now keep a pair of booties on cold trips, and they seem to help stop my toes chilling faster than the rest of me (and I sleep pretty cold).
> [...]
>
> post 1 of zillions!
>
> why is it very faulty logic?
>
> As you get cold your body removes blood circulation from the extremities making them cold. Other parts of your body produce/let off more heat than your extremities so it makes sense to allow that heat to warm the sleeping bag as a whole in order to keep your extremities warmer. sleeping naked in a good sleeping bag will keep you warm and feeling warm as all parts of your bady are kept at a comfortable level. It is not a case of naked is warmer as your core body temp will be higher with clothes but naked you will feel warmer and in extreme situations the chances of frostbite will be less though obviously in extreme situations comfort might be substituted for a hihger core temp.
>
> Personally i find if i wear clothes my feet will always be cold, if im naked i always end up having to stick my feet out of bag as they are too hot!
>
> post 1 of zillions!
>
> why is it very faulty logic?
>
> As you get cold your body removes blood circulation from the extremities making them cold. Other parts of your body produce/let off more heat than your extremities so it makes sense to allow that heat to warm the sleeping bag as a whole in order to keep your extremities warmer. sleeping naked in a good sleeping bag will keep you warm and feeling warm as all parts of your bady are kept at a comfortable level. It is not a case of naked is warmer as your core body temp will be higher with clothes but naked you will feel warmer and in extreme situations the chances of frostbite will be less though obviously in extreme situations comfort might be substituted for a hihger core temp.
>
> Personally i find if i wear clothes my feet will always be cold, if im naked i always end up having to stick my feet out of bag as they are too hot!
In reply to Alasdair Fulton:
have you thought about a fleece liner? I made one cause the bought ones either had zips!? also the fleece I bought was much cosier and cost about £6, I suppose it's a bit bulky but worth it if I have room. Oh yeah and wearing a down jacket also helps
have you thought about a fleece liner? I made one cause the bought ones either had zips!? also the fleece I bought was much cosier and cost about £6, I suppose it's a bit bulky but worth it if I have room. Oh yeah and wearing a down jacket also helps
In reply to Alasdair Fulton:
I'm getting one but can't decide which. The poshest/most expensive are about £40+ but there are much cheaper ones, from £15. Here are some of the cheap-ish ones i've found (prices inc postage):
http://www.nznature.co.nz/mshop/spi//5_SIL_851
£20 - from NZ
£15 - from global.backpacker on ebay (in Singapore, 5 day delivery)
http://www.nomadtravel.co.uk/store/customer/product.php?productid=19590
£27.50
http://www.gear-zone.co.uk/eshop/Sleeping-Bag-Liners.html
£25 (not inc postage) - Sea to Summit ones
Then there's Rab ones, of course, incl a £50 heavy duty travel one with square bottom. And loads more - do a google.
I'm not sure whether to go with the cheapest or get a branded one.
I'm getting one but can't decide which. The poshest/most expensive are about £40+ but there are much cheaper ones, from £15. Here are some of the cheap-ish ones i've found (prices inc postage):
http://www.nznature.co.nz/mshop/spi//5_SIL_851
£20 - from NZ
£15 - from global.backpacker on ebay (in Singapore, 5 day delivery)
http://www.nomadtravel.co.uk/store/customer/product.php?productid=19590
£27.50
http://www.gear-zone.co.uk/eshop/Sleeping-Bag-Liners.html
£25 (not inc postage) - Sea to Summit ones
Then there's Rab ones, of course, incl a £50 heavy duty travel one with square bottom. And loads more - do a google.
I'm not sure whether to go with the cheapest or get a branded one.
In reply to Alasdair Fulton:
Just get a summit 1000 + liner + wear your down jacket inside = anywhere very cold,you will be too hot !
Just get a summit 1000 + liner + wear your down jacket inside = anywhere very cold,you will be too hot !
In reply to papajon:
ok mr troll? i have nothing better to do so in answer to your post.
Your experiment is fatally flawed but cant be bother to say why but basically if you are cold naked in your sleeping bag - buy a better sleeping bag. a heavier sleeping bag will be more efficient than the same weight of clothes so leave your night clothes at home and take the heavier sleeping bag.
simple. a couple of 100g in a fleece liner or added clothes will be better used as a couple of 100g of added down.
ok mr troll? i have nothing better to do so in answer to your post.
Your experiment is fatally flawed but cant be bother to say why but basically if you are cold naked in your sleeping bag - buy a better sleeping bag. a heavier sleeping bag will be more efficient than the same weight of clothes so leave your night clothes at home and take the heavier sleeping bag.
simple. a couple of 100g in a fleece liner or added clothes will be better used as a couple of 100g of added down.
In reply to epik:
>simple. a couple of 100g in a fleece liner or added clothes will be better used as a couple of 100g of added down.
What are you saying, that it is better than down or not as good as another 100g of down?
If you think extra down is better then consider this. When your superfilled down bag is wet you will be cold but with a fleece liner you will have something that MAY help you keep warm. Sometimes a consideration people forget.
>simple. a couple of 100g in a fleece liner or added clothes will be better used as a couple of 100g of added down.
What are you saying, that it is better than down or not as good as another 100g of down?
If you think extra down is better then consider this. When your superfilled down bag is wet you will be cold but with a fleece liner you will have something that MAY help you keep warm. Sometimes a consideration people forget.
In reply to sutty:
im saying 100g of down will be warmer than a 100g of fleece!
People often buy "lightweight" sleeping bags to cut weight and then take extra clothes or a liner because they are too cold whihc finally will make them heavier than just buying a warmer sleeping bag.
be interesting to test the TOG rating of a soaking sleeping bag as apposed to a layer of fleece. i wouldnt be suprised if 100g of wet down is still warmer than fleece and 100g of synthetic will definetely be better than fleece. be interesting to do the test some time though currently i have no figures.
will agree that a liner can add versitility especially when on a budget but i would still sleep naked as apposed to taking extra clothes. just to clarify i like liners just dont like sleeping in clothes.
im saying 100g of down will be warmer than a 100g of fleece!
People often buy "lightweight" sleeping bags to cut weight and then take extra clothes or a liner because they are too cold whihc finally will make them heavier than just buying a warmer sleeping bag.
be interesting to test the TOG rating of a soaking sleeping bag as apposed to a layer of fleece. i wouldnt be suprised if 100g of wet down is still warmer than fleece and 100g of synthetic will definetely be better than fleece. be interesting to do the test some time though currently i have no figures.
will agree that a liner can add versitility especially when on a budget but i would still sleep naked as apposed to taking extra clothes. just to clarify i like liners just dont like sleeping in clothes.
In reply to epik:
Yes I agree that dry down is thermally more efficient, but in the real world clothes are more use as they serve a "dual" purpose - ie you can wear them during the day as well. Extra weight in a maggot is effectively dead weight if you have to carry it round.
> (In reply to papajon)
>
> Your experiment is fatally flawed but cant be bother to say why but basically if you are cold naked in your sleeping bag - buy a better sleeping bag. a heavier sleeping bag will be more efficient than the same weight of clothes so leave your night clothes at home and take the heavier sleeping bag.
>
> simple. a couple of 100g in a fleece liner or added clothes will be better used as a couple of 100g of added down.
>
> Your experiment is fatally flawed but cant be bother to say why but basically if you are cold naked in your sleeping bag - buy a better sleeping bag. a heavier sleeping bag will be more efficient than the same weight of clothes so leave your night clothes at home and take the heavier sleeping bag.
>
> simple. a couple of 100g in a fleece liner or added clothes will be better used as a couple of 100g of added down.
Yes I agree that dry down is thermally more efficient, but in the real world clothes are more use as they serve a "dual" purpose - ie you can wear them during the day as well. Extra weight in a maggot is effectively dead weight if you have to carry it round.
In reply to MJH:
True but unfortunately damp clothes cool you down when sleeping and any clothes you wear in the day will have sweat in them thus are not the best things to sleep in thus my comment about the night set of clothes. Also working on your principle can be very dangerous.
i know a number of groups that have taken light sleeping bags on expedition in the idea they will sleep in their clothes but then their clothes get wet or even just damp and then are forced to either sleep in damp cltohes or sleep in a sleeping bag that is no-where near warm enough for the conditions. either way you are in for a rough night.
when i have tried to travel light in the past i take one set of clothes and a warm sleeping bag then clothes get wet in day so i take them off and leave them in tent porch to avoid getting dampness in tent. then sleep naked in sleeping bag and get good night sleep. then in morning put wet clothes back on. repeated for rest of expedition and perfectly lightweight enough for me but whatever you feel comfortable with! personally i find sleeping in day clothes minging and i suffer tangle-itus with liners but thats just me.
> Yes I agree that dry down is thermally more efficient, but in the real world clothes are more use as they serve a "dual" purpose - ie you can wear them during the day as well. Extra weight in a maggot is effectively dead weight if you have to carry it round.
True but unfortunately damp clothes cool you down when sleeping and any clothes you wear in the day will have sweat in them thus are not the best things to sleep in thus my comment about the night set of clothes. Also working on your principle can be very dangerous.
i know a number of groups that have taken light sleeping bags on expedition in the idea they will sleep in their clothes but then their clothes get wet or even just damp and then are forced to either sleep in damp cltohes or sleep in a sleeping bag that is no-where near warm enough for the conditions. either way you are in for a rough night.
when i have tried to travel light in the past i take one set of clothes and a warm sleeping bag then clothes get wet in day so i take them off and leave them in tent porch to avoid getting dampness in tent. then sleep naked in sleeping bag and get good night sleep. then in morning put wet clothes back on. repeated for rest of expedition and perfectly lightweight enough for me but whatever you feel comfortable with! personally i find sleeping in day clothes minging and i suffer tangle-itus with liners but thats just me.
In reply to Alasdair Fulton: i think there are a lot of extra variables that have been added to the OP original question. However valid they may be in 'real life' i think you need to isolate and simplify.
You have a sleeping bag. Assuming you are sleeping naked, all the zips are done up, will adding a silk liner keep you warmer than if you were not using that silk liner, and if so by how much in proportion to the bags quoted tog rating.
You have a sleeping bag. Assuming you are sleeping naked, all the zips are done up, will adding a silk liner keep you warmer than if you were not using that silk liner, and if so by how much in proportion to the bags quoted tog rating.
In reply to Alasdair Fulton:
Lidl selling their silk liners for £10 from Monday:
http://www.lidl.co.uk/gb/home.nsf/pages/c.o.20050905.index
In some areas, anyway...
Lidl selling their silk liners for £10 from Monday:
http://www.lidl.co.uk/gb/home.nsf/pages/c.o.20050905.index
In some areas, anyway...
In reply to alpkid:
Since we seem to all be going in lovely circles I asked the nice folks at RAB and Alpkit for their views on these matters, figuring that bag designers know more than we plebs.
Rab says that a silk liner probably adds 1 to 2 degrees to the warmth of a bag, but have no hard data to back this up.
On the question of sleeping naked, both Rab and Alpkit say wearing more keeps you warmer.
Rab said:
Regarding clothing, I think there is no doubt that wearing thermal underwear or a microfleece type top increases your warmth in the bag. However wearing too much can have a negative effect by compressing the layers of insulation, and even the bag itself, and this is to be avoided
Apkit figure:
In short the idea that you would be warmer at minus -25 in say a -15 Down Bag .....naked, rather than with some clothes is a complete load of.....tosh.
Since we seem to all be going in lovely circles I asked the nice folks at RAB and Alpkit for their views on these matters, figuring that bag designers know more than we plebs.
Rab says that a silk liner probably adds 1 to 2 degrees to the warmth of a bag, but have no hard data to back this up.
On the question of sleeping naked, both Rab and Alpkit say wearing more keeps you warmer.
Rab said:
Regarding clothing, I think there is no doubt that wearing thermal underwear or a microfleece type top increases your warmth in the bag. However wearing too much can have a negative effect by compressing the layers of insulation, and even the bag itself, and this is to be avoided
Apkit figure:
In short the idea that you would be warmer at minus -25 in say a -15 Down Bag .....naked, rather than with some clothes is a complete load of.....tosh.
In reply to papajon:I have heard that you would be warmer naked in your old bag than in clothes,however my mate told me this after drinking vintage westons cider ! Though I would say layering thin clothes would be best as you can strip off the layers when you get too hot.
Did I mention my summit 1000 bag ?
Did I mention my summit 1000 bag ?
In reply to papajon:
i feel everso slightly like i have been stiched up here! wouldnt be so kind to mention which "bag designer" you spoke to? Sounds like Neil at Rab and Nick at Alpkit?
Maybe you can ask alpkit which would be the lightest for warmth?
a) -25 in a -25 bag naked
or
b) -25 in a -15 bag and enough clothes to make up the extra -10 needed?
option a will be lightest for warmth and i doubt any sleeping bag manufacture is going to be silly enough to pretend it isn't.
You are missing my point that down IS the best insulator for weight available in the market (if it wasn't we would make sleeping bags out of purely fleece - which we dont) so gram for gram you are better taking an appropriately seasoned bag than taking extra clothes (or infact a liner)to make up the difference in rating.
is your troll over now? commited effort though to email them
i feel everso slightly like i have been stiched up here! wouldnt be so kind to mention which "bag designer" you spoke to? Sounds like Neil at Rab and Nick at Alpkit?
Maybe you can ask alpkit which would be the lightest for warmth?
a) -25 in a -25 bag naked
or
b) -25 in a -15 bag and enough clothes to make up the extra -10 needed?
option a will be lightest for warmth and i doubt any sleeping bag manufacture is going to be silly enough to pretend it isn't.
You are missing my point that down IS the best insulator for weight available in the market (if it wasn't we would make sleeping bags out of purely fleece - which we dont) so gram for gram you are better taking an appropriately seasoned bag than taking extra clothes (or infact a liner)to make up the difference in rating.
is your troll over now? commited effort though to email them
In reply to epik:
I think it's taken for granted that most people will take some form of clothing into the hills with them. Put simply, if you don't need to wear your clothes at night, then you're probabally carrying too much sleeping bag. Also, I would't fancy the getting up in the morning bit very much if I wasn't wearing anything!
Mark
> Maybe you can ask alpkit which would be the lightest for warmth?
>
> a) -25 in a -25 bag naked
> b) -25 in a -15 bag and enough clothes to make up the extra -10 needed?
>
> a) -25 in a -25 bag naked
> b) -25 in a -15 bag and enough clothes to make up the extra -10 needed?
> option a will be lightest for warmth ...
I think it's taken for granted that most people will take some form of clothing into the hills with them. Put simply, if you don't need to wear your clothes at night, then you're probabally carrying too much sleeping bag. Also, I would't fancy the getting up in the morning bit very much if I wasn't wearing anything!
Mark
In reply to epik:
We "only" answered the question ....is it warmer with or with out clothing. Same bag - Same "outside" temp.
The best way to explain to those committed to the idea that it is warmer to sleep naked is pose the following senerio....
"it is -25 and you are sleeping in a -15 bag you have the option of being given a thermal top to wear"
I know what i would do.
Cheers
Nick
We "only" answered the question ....is it warmer with or with out clothing. Same bag - Same "outside" temp.
The best way to explain to those committed to the idea that it is warmer to sleep naked is pose the following senerio....
"it is -25 and you are sleeping in a -15 bag you have the option of being given a thermal top to wear"
I know what i would do.
Cheers
Nick
In reply to Anonymous:
good guess i thought i might be you but sounded very neil esque!
> (In reply to epik)
>
> Oh sorry; just saw your bit about not carrying extra clothes.
>
> Mark
>
> Oh sorry; just saw your bit about not carrying extra clothes.
>
> Mark
good guess i thought i might be you but sounded very neil esque!
In reply to Anonymous:
if you are already wearing your clothes when you get up and its cold, you dont have anything extra to put on, while you pack up, and therefore get cold, its better to sleep in max 1 thin layer or no clothing, with your clothes in the bag reducing the air space, and staying warm so you have warm clothes to put on when you have to get up, its different rule for +10 camping than it is for -10 camping, and most people carry too much bag anyway, because they wont shell out on a decent one to save weight
> (In reply to epik)
>
> [...]
>
> [...]
>
> I think it's taken for granted that most people will take some form of clothing into the hills with them. Put simply, if you don't need to wear your clothes at night, then you're probabally carrying too much sleeping bag. Also, I would't fancy the getting up in the morning bit very much if I wasn't wearing anything!
>
> Mark
>
> [...]
>
> [...]
>
> I think it's taken for granted that most people will take some form of clothing into the hills with them. Put simply, if you don't need to wear your clothes at night, then you're probabally carrying too much sleeping bag. Also, I would't fancy the getting up in the morning bit very much if I wasn't wearing anything!
>
> Mark
if you are already wearing your clothes when you get up and its cold, you dont have anything extra to put on, while you pack up, and therefore get cold, its better to sleep in max 1 thin layer or no clothing, with your clothes in the bag reducing the air space, and staying warm so you have warm clothes to put on when you have to get up, its different rule for +10 camping than it is for -10 camping, and most people carry too much bag anyway, because they wont shell out on a decent one to save weight
Another thought: If silk liners really did add a season to your sleeping bag, would it not be very easy (and cheap) to make a 4 season sleeping bag out of silk liners? It would be much lighter than down...
Mark
In reply to gear boy:
I can see your point, but I've never found that to be true. If I'm hot when I wake up, the getting out of the bag bit doesn't seem to bother me (even if I don't have spare clothes), wheras if I'm cold, having spare clothes seems to do nothing. Each to their own I suppose.
Mark
> if you are already wearing your clothes when you get up and its cold, you dont have anything extra to put on, while you pack up, and therefore get cold, its better to sleep in max 1 thin layer or no clothing, with your clothes in the bag reducing the air space, and staying warm so you have warm clothes to put on when you have to get up...
I can see your point, but I've never found that to be true. If I'm hot when I wake up, the getting out of the bag bit doesn't seem to bother me (even if I don't have spare clothes), wheras if I'm cold, having spare clothes seems to do nothing. Each to their own I suppose.
Mark
In reply to Alasdair Fulton: as to one companies answer on silk temp adding, try www.cocoon.at
In reply to Anonymous: as for me i dont use a liner, get twisted in them, sleep in the buff or very little, usually wrap down jkt round feet if cold, dont usually get cold, in uk and have a -9 bag i have used at -16 so each to their own! i find getting up early on alpine routes easier, if i can put some clothes on before moving, and the chill of the air wakes me as i put on a brew
In reply to Anonymous:
And it would be ohh so nice on your skin must be a reason why no-one does that?
>
> Another thought: If silk liners really did add a season to your sleeping bag, would it not be very easy (and cheap) to make a 4 season sleeping bag out of silk liners? It would be much lighter than down...
> Another thought: If silk liners really did add a season to your sleeping bag, would it not be very easy (and cheap) to make a 4 season sleeping bag out of silk liners? It would be much lighter than down...
And it would be ohh so nice on your skin must be a reason why no-one does that?
In reply to Alpnick:
? ok i have a query which none of us can prove or disprove as we dont have figures but
temp ratings are based on personal surveys carried out in BS case by the Army. comfort rating is a temp at whihc big strong army type blokes said they felt fine and comfortable and extreme temp ratings are the temp at which it can become dangerous.
so comfort rating is a subjective figure whereas extreme is a scientific figure based on core temp dropping/hypothermia onset and death.
i would bet that if doing that survey again of the thousands of men you would find
in clothes a man would give a comfort rating of say -10 and an extreme on say -20.
if you were naked i would bet that although the extreme temp would go down to maybe -17 your comfort survey would have gone up to -12.
May even go as far as saying you would have less chance of ever reaching an extreme temp if your body was comfortable but that would be way harder to prove. none of us know but it would be interesting to do. though totally off thread now so appologies one and all!
p.s. if you offered me the thermal top i would take it but only to wrap my feet in it and sleep with a naked torso and i bet i get a better nights sleep than you
? ok i have a query which none of us can prove or disprove as we dont have figures but
temp ratings are based on personal surveys carried out in BS case by the Army. comfort rating is a temp at whihc big strong army type blokes said they felt fine and comfortable and extreme temp ratings are the temp at which it can become dangerous.
so comfort rating is a subjective figure whereas extreme is a scientific figure based on core temp dropping/hypothermia onset and death.
i would bet that if doing that survey again of the thousands of men you would find
in clothes a man would give a comfort rating of say -10 and an extreme on say -20.
if you were naked i would bet that although the extreme temp would go down to maybe -17 your comfort survey would have gone up to -12.
May even go as far as saying you would have less chance of ever reaching an extreme temp if your body was comfortable but that would be way harder to prove. none of us know but it would be interesting to do. though totally off thread now so appologies one and all!
p.s. if you offered me the thermal top i would take it but only to wrap my feet in it and sleep with a naked torso and i bet i get a better nights sleep than you
In reply to epik: i dont think there has been any stitching up anywhere. No one has questioned that down IS the best insulator on the market. The question was would a silk liner (or as it has now been widened: clothes) add to the warmth of the sleeping bag. Which it would. The reasons why someone would want to take a silk liner instead of a warmer bag are I imagine that they already have a sleeping bag and dont want to buy a new one and/or like the convenience of a liner to keep the bag clean.
Everything else should be addressed in a different question, no?
Everything else should be addressed in a different question, no?
In reply to Anonymous: from what i read the consensus was 1 or 2 degrees - hardly adds a season rating. I would think most of this warmth is gained by trapping air since the air inside a bag is hardly moving anyway.
In reply to epik:
No intention to stich up, dude. Appologies if that's how it came across. And yes, I do agree with your point that down is the best insulator for weight. No argument there. Only point I was making in suggesting wearing cloths in bed (in response to an original question) is that if you've got a bag that's not entirely up to the job that's the best way of making do.
No intention to stich up, dude. Appologies if that's how it came across. And yes, I do agree with your point that down is the best insulator for weight. No argument there. Only point I was making in suggesting wearing cloths in bed (in response to an original question) is that if you've got a bag that's not entirely up to the job that's the best way of making do.
In reply to papajon:
no probs just found it funny the two "experts" you chose to ask prior history and all that!
however i will still stand by my statement that clothes are not the best way of making do as you put it and can cause a reduction in comfort temp rating!
liners are good and undoubtadly add temp but clothes do not always help. bizarre logic? well what about the fact that people think if you took a 1200g bag and added another 1200g of down to it it would be way warmer? (most shells are the same size throughout a bag range) sound correct logic? might sound logical but most good bag designers will accept that there is a level at which adding down to a shell will no longer add warmth and will infact start to detract from the temp rating. reason being that you begin to compress the down and effect its thermal resistance as you squeeze the air out. (infact if you work out the size of baffles for a given amount of down to get perfection you would be surprised how big the baffles would be). so bizarre logic is not always wrong.
i've slept in a 3 man tent with two mates who both had almost identical bags. i worn nothing apart from clean on dry socks. they wore clothes (fleece, tracksuit bottoms, socks, tshirt) in the night the 1L bottle of water in teh tent froze but in the morning i was warm and had slept fine though my two mates (although both claimed to have sweaty armpits due to teh fleece) didnt get a seconds sleep due to shivering in one case and the other said his feet were too cold to sleep. Im happy with my logic and your happy with yours but i'd suggest you experiment with your system and see what works best with an open mind and maybe one day someone will do a full study and find the science to prove the facts. until then i'll stick with the power of down and sharing heat
no probs just found it funny the two "experts" you chose to ask prior history and all that!
however i will still stand by my statement that clothes are not the best way of making do as you put it and can cause a reduction in comfort temp rating!
liners are good and undoubtadly add temp but clothes do not always help. bizarre logic? well what about the fact that people think if you took a 1200g bag and added another 1200g of down to it it would be way warmer? (most shells are the same size throughout a bag range) sound correct logic? might sound logical but most good bag designers will accept that there is a level at which adding down to a shell will no longer add warmth and will infact start to detract from the temp rating. reason being that you begin to compress the down and effect its thermal resistance as you squeeze the air out. (infact if you work out the size of baffles for a given amount of down to get perfection you would be surprised how big the baffles would be). so bizarre logic is not always wrong.
i've slept in a 3 man tent with two mates who both had almost identical bags. i worn nothing apart from clean on dry socks. they wore clothes (fleece, tracksuit bottoms, socks, tshirt) in the night the 1L bottle of water in teh tent froze but in the morning i was warm and had slept fine though my two mates (although both claimed to have sweaty armpits due to teh fleece) didnt get a seconds sleep due to shivering in one case and the other said his feet were too cold to sleep. Im happy with my logic and your happy with yours but i'd suggest you experiment with your system and see what works best with an open mind and maybe one day someone will do a full study and find the science to prove the facts. until then i'll stick with the power of down and sharing heat
In reply to alpkid:
hi k, so you would accept that a liner works better than clothes? "this warmth is gained by trapping air" something a sleeping bag does well, something a liner also does well, something clothes do not do any where near as well.
p.s. so we do agree that gram for gram naked in a suitable bag is better than clothes in an unsuitable bag. atleast we all agree on one thing
> (In reply to Anonymous) from what i read the consensus was 1 or 2 degrees - hardly adds a season rating. I would think most of this warmth is gained by trapping air since the air inside a bag is hardly moving anyway.
hi k, so you would accept that a liner works better than clothes? "this warmth is gained by trapping air" something a sleeping bag does well, something a liner also does well, something clothes do not do any where near as well.
p.s. so we do agree that gram for gram naked in a suitable bag is better than clothes in an unsuitable bag. atleast we all agree on one thing
In reply to epik: ciao p, well depends what you are wearing of course. i have cut back on the pies lately so can wear my down jacket in my bag without compressing the down of the bag. I would say that this would be warmer than both a silk liner or thermal underwear. I know what i would rather be wearing when i need to go for a pee in the middle of the night
p.s. yes
p.s. yes
In reply to alpkid:
i like how you use the example of a down jacket whilst nick mentions a thermal top. not saying this bears any relation to your current physical statures
> i have cut back on the pies lately so can wear my down jacket in my bag without compressing the down of the bag.
i like how you use the example of a down jacket whilst nick mentions a thermal top. not saying this bears any relation to your current physical statures
In reply to alpkid:
sure anonymous (being the Rab expert that made the original reply) realises this think he was proving the point!
> (In reply to Anonymous) from what i read the consensus was 1 or 2 degrees - hardly adds a season rating.
sure anonymous (being the Rab expert that made the original reply) realises this think he was proving the point!
Thanks for the input everyone, very interesting, what i've worked out so far : -
I prob should have got a bag with more down, as it's the lightest insulator, but, I got it cheap, so it's all i've got.
If I'm stuck somewhere really cold, a silk liner is only going to add a couple of degrees max, not much for £30 (however it will keep the bag cleaner)
Any thoughts on my dual-bag idea?
(for those who didn't read that bit - what rating (roughly the "comfort temp") do yo think a quantum 400 bag, with a snugpag softie 3 (very thin 2 season synthetic) on top would be?
Ally.
I prob should have got a bag with more down, as it's the lightest insulator, but, I got it cheap, so it's all i've got.
If I'm stuck somewhere really cold, a silk liner is only going to add a couple of degrees max, not much for £30 (however it will keep the bag cleaner)
Any thoughts on my dual-bag idea?
(for those who didn't read that bit - what rating (roughly the "comfort temp") do yo think a quantum 400 bag, with a snugpag softie 3 (very thin 2 season synthetic) on top would be?
Ally.
Just a thought, someone mentioned that the shell on different weight bags in the same range is the same. Can you get additional down added into a bag?
In reply to alpkid:
In cold conditions, there is only one way to pee at night - use a pee bottle! Any other approach looses too much heat from your core.
It's also worth mentioning in this thread (not obviously seen this mentioned as I've scanned down the thread) that the quality of down used in a bag is also *very* important. Certainly (AFAIK), some reputable companies recently (within the last year or three?) had problems with the quality of down being used by their Chinese "manufacturers".
In cold conditions, there is only one way to pee at night - use a pee bottle! Any other approach looses too much heat from your core.
It's also worth mentioning in this thread (not obviously seen this mentioned as I've scanned down the thread) that the quality of down used in a bag is also *very* important. Certainly (AFAIK), some reputable companies recently (within the last year or three?) had problems with the quality of down being used by their Chinese "manufacturers".
In reply to epik:
The thing that makes me question things with comfort and extreme ratings are : the two bags I have are comfort -3/-25 and extreme -7/-30,now the difference is only 4-5 degrees,not much is it ?
the Rab bag I have says that it is wider at the top so you can wear your down jacket inside (god forbid you are still cold!)Though I have never tried ,i'm guessing it would be very hot indeed,also on the subject of Rab,in their catalouge it states that the summit 800 and 1000 have the same pack size of 29x16 for an extra 200g which bag would you choice ?
As for the liner,I use one,not for extra warmth but to keep the bag clean and to sleep in in the trek in as a full on winter bag is to hot
The thing that makes me question things with comfort and extreme ratings are : the two bags I have are comfort -3/-25 and extreme -7/-30,now the difference is only 4-5 degrees,not much is it ?
the Rab bag I have says that it is wider at the top so you can wear your down jacket inside (god forbid you are still cold!)Though I have never tried ,i'm guessing it would be very hot indeed,also on the subject of Rab,in their catalouge it states that the summit 800 and 1000 have the same pack size of 29x16 for an extra 200g which bag would you choice ?
As for the liner,I use one,not for extra warmth but to keep the bag clean and to sleep in in the trek in as a full on winter bag is to hot
In reply to Alasdair Fulton:
Well theoretically we can add the two thermal resistances of the two bags and give you a temp rating for the two put together however this is based on you find a way to put them together without crushing down and also relies on you being able to close both bags.
Assuming both companies use BS temp rating charts which is a massive assumption and i almost guarantee neither do but we have to assume this to be able to work it out so.....
Q400 rated to -5 so thermal resistance of aprox 1.220
softie 3 rated to -10 (anybody else see the problem with this temp rating?) so thermal resitance of approx 1.380
so combined they would have a thermal resistance of 2.600 but unfortunately the BS chart stops at 1.540 which is -15.2C so we would have to guess but it will bebetter than -15C though all this is theory based on data so in practice it might not be the same but i would say it could be equivelent to a -20bag
p.s. if you could work out some way of sleeping on top of the doubled up synthetic bag but put the doubled up down bag on top of you this would be better than sleeping in both at once but i suspect you will have to sleep in teh Q400 and put the synth over teh top.
> Any thoughts on my dual-bag idea?
>
> (for those who didn't read that bit - what rating (roughly the "comfort temp") do yo think a quantum 400 bag, with a snugpag softie 3 (very thin 2 season synthetic) on top would be?
>
> (for those who didn't read that bit - what rating (roughly the "comfort temp") do yo think a quantum 400 bag, with a snugpag softie 3 (very thin 2 season synthetic) on top would be?
Well theoretically we can add the two thermal resistances of the two bags and give you a temp rating for the two put together however this is based on you find a way to put them together without crushing down and also relies on you being able to close both bags.
Assuming both companies use BS temp rating charts which is a massive assumption and i almost guarantee neither do but we have to assume this to be able to work it out so.....
Q400 rated to -5 so thermal resistance of aprox 1.220
softie 3 rated to -10 (anybody else see the problem with this temp rating?) so thermal resitance of approx 1.380
so combined they would have a thermal resistance of 2.600 but unfortunately the BS chart stops at 1.540 which is -15.2C so we would have to guess but it will bebetter than -15C though all this is theory based on data so in practice it might not be the same but i would say it could be equivelent to a -20bag
p.s. if you could work out some way of sleeping on top of the doubled up synthetic bag but put the doubled up down bag on top of you this would be better than sleeping in both at once but i suspect you will have to sleep in teh Q400 and put the synth over teh top.
In reply to anonymoss:
Could be an issue in future as bird flu once again destroys down stock and makes it even harder for chinese factories to fulfill there orders for top end down bags? must be tempting when pushed on price from both sides to make the down last longer (mix it, under fill etc) but i am sure they would never contemplate it
> Certainly (AFAIK), some reputable companies recently (within the last year or three?) had problems with the quality of down being used by their Chinese "manufacturers".
Could be an issue in future as bird flu once again destroys down stock and makes it even harder for chinese factories to fulfill there orders for top end down bags? must be tempting when pushed on price from both sides to make the down last longer (mix it, under fill etc) but i am sure they would never contemplate it
In reply to epik:
ALMOST identical bags. So not identical, then.
TWO MATES. Who no doubt have different physiologies, as we all do. Had you all eaten and drunk the same amount before going to bed? Were you all the same temperature before you got into your bags? Are you all the same size and bodyweight? Maybe you sleep hot, and they don't.
I agree that if you wear so much clothing that you compress the down in the bag, it can't work. However, since I'm not a fat pie eater, there's plenty of room inside my bags to wear quite a bit of insulating clothing. And I suspect that is the case for most people.
I also agree that simply adding more down to a bag can be counter-productive, as the down can't loft fully, and dead air space becomes filled with more conductive down fibres.
The only argument I've seen for sleeping naked is that the down in the bag requires body heat to loft fully and achieve its full insulating properties. If you wear insulating clothing, this heat may not reach the bag, so it is less effective. It's not an entirely convincing argument, as, in order for you to feel cold, you MUST be losing heat to the system (outside the bag), more heat than you would if the bag were working correctly. Why then does this higher heat flux not warm the down?
It may be that clothing traps insensible perspiration closer to the body, which somehow makes you feel colder. With no clothing, the perspiration may pass into the bag, and this might make you feel more comfortable.
> i've slept in a 3 man tent with two mates who both had almost identical bags
ALMOST identical bags. So not identical, then.
TWO MATES. Who no doubt have different physiologies, as we all do. Had you all eaten and drunk the same amount before going to bed? Were you all the same temperature before you got into your bags? Are you all the same size and bodyweight? Maybe you sleep hot, and they don't.
I agree that if you wear so much clothing that you compress the down in the bag, it can't work. However, since I'm not a fat pie eater, there's plenty of room inside my bags to wear quite a bit of insulating clothing. And I suspect that is the case for most people.
I also agree that simply adding more down to a bag can be counter-productive, as the down can't loft fully, and dead air space becomes filled with more conductive down fibres.
The only argument I've seen for sleeping naked is that the down in the bag requires body heat to loft fully and achieve its full insulating properties. If you wear insulating clothing, this heat may not reach the bag, so it is less effective. It's not an entirely convincing argument, as, in order for you to feel cold, you MUST be losing heat to the system (outside the bag), more heat than you would if the bag were working correctly. Why then does this higher heat flux not warm the down?
It may be that clothing traps insensible perspiration closer to the body, which somehow makes you feel colder. With no clothing, the perspiration may pass into the bag, and this might make you feel more comfortable.
In reply to Alasdair Fulton:
Get a £10 Lidl one, then... next Monday.
For dual bag systems, put the down inside, and the synthetic outside, so the dewpoint falls in the synthetic. And make sure the outer bag is big enough not to compress the down.
> a silk liner is only going to add a couple of degrees max, not much for £30
Get a £10 Lidl one, then... next Monday.
For dual bag systems, put the down inside, and the synthetic outside, so the dewpoint falls in the synthetic. And make sure the outer bag is big enough not to compress the down.
In reply to captain paranoia:
this thread is getting quite long so in short (ish),
2 of us had identical bags, 1 had another model though same make and same temp rating. we were all same build and had all lived identical lives for the 3 days of the trip not that it really matters as it was an example rather than a scientific prover!
As regards the rest of your thread please see my earlier comments about comfort vs extreme temp ratings and how they are devised and by your own words you admit you may be more comfortable naked thus the comfort rating would be better though no-one is argueing the extreme temp would follow this trend.
This is never going to be proven by us. i have spoke to a few of my mates at Rab and amoungst us we are all of mixed oppinion about it. some agree with me and some do not but then that is always the way
would be an interesting subject for a PhD maybe i will email an extreme cold user and ask his advice some time!
this thread is getting quite long so in short (ish),
2 of us had identical bags, 1 had another model though same make and same temp rating. we were all same build and had all lived identical lives for the 3 days of the trip not that it really matters as it was an example rather than a scientific prover!
As regards the rest of your thread please see my earlier comments about comfort vs extreme temp ratings and how they are devised and by your own words you admit you may be more comfortable naked thus the comfort rating would be better though no-one is argueing the extreme temp would follow this trend.
This is never going to be proven by us. i have spoke to a few of my mates at Rab and amoungst us we are all of mixed oppinion about it. some agree with me and some do not but then that is always the way
would be an interesting subject for a PhD maybe i will email an extreme cold user and ask his advice some time!
In reply to Alasdair Fulton:
Probably not as good as a hot cup of tea before bed,but we may never know
Probably not as good as a hot cup of tea before bed,but we may never know
In reply to epik: Thanks for the scientific approach.
One point, the softie 3 is rated to +5 deg c, so how does that effect your model?
One point, the softie 3 is rated to +5 deg c, so how does that effect your model?
In reply to Alasdair Fulton:
ahh, i must admit when i looked on their website i thought a softie 3 seemed strange to have a -10 so i must have read it wrong. +5 would change the rating and i would be able to give a more accurate temp rating but i dont have the BS chart to hand any more as i am not at home so sorry have to pass on that one.
> (In reply to epik) Thanks for the scientific approach.
>
> One point, the softie 3 is rated to +5 deg c, so how does that effect your model?
>
> One point, the softie 3 is rated to +5 deg c, so how does that effect your model?
ahh, i must admit when i looked on their website i thought a softie 3 seemed strange to have a -10 so i must have read it wrong. +5 would change the rating and i would be able to give a more accurate temp rating but i dont have the BS chart to hand any more as i am not at home so sorry have to pass on that one.
In reply to epik:
Morning
Q400 rated to -5 so thermal resistance of aprox 1.220
softie 3 rated to -10 thermal resitance of approx 1.380
what measure of thermal resisitance are you using?
Cheers
Nick
Morning
Q400 rated to -5 so thermal resistance of aprox 1.220
softie 3 rated to -10 thermal resitance of approx 1.380
what measure of thermal resisitance are you using?
Cheers
Nick
In reply to Alpnick: Bit late joining this particular argument, but my (black) silk liner definitely makes me appreciably warmer in my Snugpack Softie bag. It can make the difference between an uncomfortable night due to being cold, and a comfortable night due to being warm. And the only item of clothing I usually wear inside either is a pair of warm socks as my feet seem to control my body temperature: if I can keep them warm, the rest of me is generally fine.
Jo
Jo
In reply to Alasdair Fulton:
rab can add down into bags as could mountaineering designs, but cost may be high, if you do, i would only put it in the top and foot area, as its compressed under your body, and as sais earlier, too much will have a negative effect
> Just a thought, someone mentioned that the shell on different weight bags in the same range is the same. Can you get additional down added into a bag?
rab can add down into bags as could mountaineering designs, but cost may be high, if you do, i would only put it in the top and foot area, as its compressed under your body, and as sais earlier, too much will have a negative effect
In reply to man_in_the_alps:
also their summit 300 is 40x23!!??
i am guessing they have the pack sizes upside down ,looking at them
> (In reply to epik)
> also on the subject of Rab,in their catalouge it states that the summit 800 and 1000 have the same pack size of 29x16 for an extra 200g which bag would you choice ?
> also on the subject of Rab,in their catalouge it states that the summit 800 and 1000 have the same pack size of 29x16 for an extra 200g which bag would you choice ?
also their summit 300 is 40x23!!??
i am guessing they have the pack sizes upside down ,looking at them
In reply to man_in_the_alps:
I have to agree that sleeping in a bag naked feels much warmer. I was unconvinced, until one very cold weeked in Kielder. First night spent wearing clothes, very cold, second night a friend convinced me to try naked and slept really well and warm. Plently of room in bag before you all say thats because I compressed the down etc.
I'm converted and I'm staying that way!
I have to agree that sleeping in a bag naked feels much warmer. I was unconvinced, until one very cold weeked in Kielder. First night spent wearing clothes, very cold, second night a friend convinced me to try naked and slept really well and warm. Plently of room in bag before you all say thats because I compressed the down etc.
I'm converted and I'm staying that way!
In reply to Alasdair Fulton: more against the naked is warmer myth..
"It seems that the popular saying is incorrect. There is more heat loss if
you bring the heat source (warm body) closer to the heat sink (cold air or
ground). With the clothes off, the only barrier to the transfer of heat
from the body to the outside is the sleeping bag wall. Addition of cloths
can only increase this resistance and lead to lower heat loss."
http://www.newton.dep.anl.gov/askasci/gen01/gen01182.htm
"The way you dress can also make a difference in how warmly you sleep. It's a myth that you sleep warmer when naked in your bag. Clothing is insulation, provided it's dry. So bring a spare set of undies to sleep in."
http://www.sierradesigns.com/bags.warm.html
"It seems that the popular saying is incorrect. There is more heat loss if
you bring the heat source (warm body) closer to the heat sink (cold air or
ground). With the clothes off, the only barrier to the transfer of heat
from the body to the outside is the sleeping bag wall. Addition of cloths
can only increase this resistance and lead to lower heat loss."
http://www.newton.dep.anl.gov/askasci/gen01/gen01182.htm
"The way you dress can also make a difference in how warmly you sleep. It's a myth that you sleep warmer when naked in your bag. Clothing is insulation, provided it's dry. So bring a spare set of undies to sleep in."
http://www.sierradesigns.com/bags.warm.html
In reply to gear boy: Oh year,never noticed that !
I got the pack size down on my summit 1000 by using a compression sack over the standard stuff sac,it may be slightly wider,but is a lot shorter
I got the pack size down on my summit 1000 by using a compression sack over the standard stuff sac,it may be slightly wider,but is a lot shorter
In reply to man_in_the_alps:
personnally i wouldnt recommend compresion sacs with down bags, as over compression of the down doesnt help, i prefer to use a suitable sized stuff sac, and by the time i have put stuff in my sac, it flattens out to available space, i found using compression sacs a bit like trying to pack footballs, end up with loads of dead space to try and fill
> I got the pack size down on my summit 1000 by using a compression sack over the standard stuff sac
personnally i wouldnt recommend compresion sacs with down bags, as over compression of the down doesnt help, i prefer to use a suitable sized stuff sac, and by the time i have put stuff in my sac, it flattens out to available space, i found using compression sacs a bit like trying to pack footballs, end up with loads of dead space to try and fill
In reply to gear boy:
I store my bag out of any sac,the only reason i have a compression sac is to fit in my duffle for trips as every bit of space counts,like next week when i'm off to Nepal : 0 )
I store my bag out of any sac,the only reason i have a compression sac is to fit in my duffle for trips as every bit of space counts,like next week when i'm off to Nepal : 0 )
In reply to Alpnick:
Morning,
I could tell you but i would have to kill you!
epik
p.s. its from the BS Standard (cant remember number) but you didnt hear that from me right
> what measure of thermal resisitance are you using?
Morning,
I could tell you but i would have to kill you!
epik
p.s. its from the BS Standard (cant remember number) but you didnt hear that from me right
In reply to epik:
Come on epik....you start questioning the so called experts, get praised for making the debate all scientific yet cant give the exact unit your using.
I know it's friday but i'll have a restless weekend if you dont tell me
Come on epik....you start questioning the so called experts, get praised for making the debate all scientific yet cant give the exact unit your using.
I know it's friday but i'll have a restless weekend if you dont tell me
In reply to epik: my new favourite thread. educational, bickering, and humourous. perfect.
epik well done i salute you and your commarades.
epik well done i salute you and your commarades.
In reply to Alpnick:
Dear Alpkit Sleepingbag Expert,
i just told you it's from the BS standard and the units used are at the top of the page in the left hand column of the chart but im not at home so cant tell you what it says as dont have a photographic memory and dont have a copy to hand but.....
being a sleeping bag manufacturer you must have a copy of the BS EN Standard to hand so can you do me a favour and look in the top left hand column of the chart and tell us all exactly what it says?
epik
> Come on epik....you start questioning the so called experts, get praised for making the debate all scientific yet cant give the exact unit your using.
>
> I know it's friday but i'll have a restless weekend if you dont tell me
>
> I know it's friday but i'll have a restless weekend if you dont tell me
Dear Alpkit Sleepingbag Expert,
i just told you it's from the BS standard and the units used are at the top of the page in the left hand column of the chart but im not at home so cant tell you what it says as dont have a photographic memory and dont have a copy to hand but.....
being a sleeping bag manufacturer you must have a copy of the BS EN Standard to hand so can you do me a favour and look in the top left hand column of the chart and tell us all exactly what it says?
epik
In reply to Adders:
well thankyou, we do our best
> (In reply to epik) my new favourite thread. educational, bickering, and humourous. perfect.
>
> epik well done i salute you and your commarades.
>
> epik well done i salute you and your commarades.
well thankyou, we do our best
In reply to epik: why dont you just phone leeds and him if he has tested with and without liners?
In reply to gear boy:
BS temp ratings are concearned with thermal resistance readings (or TOG) and then simply compair these readings to a chart with a thermal resistance number and a extreme temp, upper comfort and lower comfort (male/female) number all inline with that resistance reading. They will only be able to tell you a resistance point of view and the more layers the more resistance!
The comfort rating was done by the army who asked men when they were comfortable and as such all men wore the same items of clothing or not as the case may be. so that data is set though does change as it gets updated occasionally.
the comfort temp question i am posing is a more medical arguement so leeds will not be able to help. the body has very complicated ways of dealing with its thermostats being cold and it is this thats in question (as far as i am concearned anyway). i have heard army studies that found a man could be stopped sweating by dipping his wrists in cold water even though the temp in room was extremely high showing the wrists have a large effect of your body. (dont try this at home as it could be very dangerous) this is why you can feel very cold even with a down jacket on if your wrists are exposed, so could teh wrist and ankles also have a large effect on the comfort rating of a bag being that it is a purely adjective rating with no science behind it. Are you comfortable? yes or no? right thats your comfort rating! so does naked help keep teh thermostats in your wrists and ankles warm and thus more comfortable?
sorry a very long winded way of saying no!
> (In reply to epik) why dont you just phone leeds and him if he has tested with and without liners?
BS temp ratings are concearned with thermal resistance readings (or TOG) and then simply compair these readings to a chart with a thermal resistance number and a extreme temp, upper comfort and lower comfort (male/female) number all inline with that resistance reading. They will only be able to tell you a resistance point of view and the more layers the more resistance!
The comfort rating was done by the army who asked men when they were comfortable and as such all men wore the same items of clothing or not as the case may be. so that data is set though does change as it gets updated occasionally.
the comfort temp question i am posing is a more medical arguement so leeds will not be able to help. the body has very complicated ways of dealing with its thermostats being cold and it is this thats in question (as far as i am concearned anyway). i have heard army studies that found a man could be stopped sweating by dipping his wrists in cold water even though the temp in room was extremely high showing the wrists have a large effect of your body. (dont try this at home as it could be very dangerous) this is why you can feel very cold even with a down jacket on if your wrists are exposed, so could teh wrist and ankles also have a large effect on the comfort rating of a bag being that it is a purely adjective rating with no science behind it. Are you comfortable? yes or no? right thats your comfort rating! so does naked help keep teh thermostats in your wrists and ankles warm and thus more comfortable?
sorry a very long winded way of saying no!
In reply to gear boy:
p.s if you just want the TOG rating of a liner Rab has the TOG value of a single layer of pertex (from the top bag base when they were tested) but i cant remember it!
> (In reply to epik) why dont you just phone leeds and him if he has tested with and without liners?
p.s if you just want the TOG rating of a liner Rab has the TOG value of a single layer of pertex (from the top bag base when they were tested) but i cant remember it!
Silk liners are brilliant. They make a bag much warmer, as they seem to reduce cold spots, but they also make a bag less sticky when the weather warms up. Want one cheap (£9.99) then get to Lidl http://www.lidl.co.uk/gb/home.nsf/pages/c.o.20050905.index
get there early though because stock doesn't last long.
get there early though because stock doesn't last long.
In reply to epik:
Ditto, and I carry a lightweight set of winter weight wicking long johns and vest so that a) there is something dry to put on if a layer above naked flesh is required, and b) they take up little space in a compressible plastic bag and weigh next to nothing.
One problem with a liner is that they have a habit of wrapping themselves around you, especially if you overheat and become sweaty.
A good bag is worth its weight and a comfy night's sleep means you are more refreshed the next day. The additional (slight) weight is more than offset by the comfort.
It is also a good idea to carry a set of dry booties/socks for use at night, if the body core is comfortable and cold feet are still a problem.
Fast (?) and light doesn't have to be uncomfortable.
Ditto, and I carry a lightweight set of winter weight wicking long johns and vest so that a) there is something dry to put on if a layer above naked flesh is required, and b) they take up little space in a compressible plastic bag and weigh next to nothing.
One problem with a liner is that they have a habit of wrapping themselves around you, especially if you overheat and become sweaty.
A good bag is worth its weight and a comfy night's sleep means you are more refreshed the next day. The additional (slight) weight is more than offset by the comfort.
It is also a good idea to carry a set of dry booties/socks for use at night, if the body core is comfortable and cold feet are still a problem.
Fast (?) and light doesn't have to be uncomfortable.
In reply to epik:
Im still confused, the only thing that makes any sense is that you have used the m2k/w but when you translate this in to a temp rating i don't get the figure you came up with.
Were exactly in EN 13537:2002 does it say that a thermal resistance value (to be confirmed) of 1.220 = -5 (approx) I would make 1.22 to be 12 tog and that's well over -10.
(just to be sure... I only have two points to make
Firstly that where all talking the same the language, tog/clo/m2k/w
and
ignoring all other arguments, what i am saying is that, in an under specced bag for the conditions you will be warmer in extra clothing than without. I understand "fully" and agree that you can be more comfortable sleeping naked. But this is only when the bag is warm enough. At some point in any bag when the temperature goes below that which the bag was intended for you will start to feel cold (This is an absolute, however hard you are). So in these cases would you put on extra clothing with the hope of keeping warm or would you sleep naked getting cold.
Cheers
Nick
Im still confused, the only thing that makes any sense is that you have used the m2k/w but when you translate this in to a temp rating i don't get the figure you came up with.
Were exactly in EN 13537:2002 does it say that a thermal resistance value (to be confirmed) of 1.220 = -5 (approx) I would make 1.22 to be 12 tog and that's well over -10.
(just to be sure... I only have two points to make
Firstly that where all talking the same the language, tog/clo/m2k/w
and
ignoring all other arguments, what i am saying is that, in an under specced bag for the conditions you will be warmer in extra clothing than without. I understand "fully" and agree that you can be more comfortable sleeping naked. But this is only when the bag is warm enough. At some point in any bag when the temperature goes below that which the bag was intended for you will start to feel cold (This is an absolute, however hard you are). So in these cases would you put on extra clothing with the hope of keeping warm or would you sleep naked getting cold.
Cheers
Nick
In reply to epik: so in theory, if tog rating for a layer of silk is applied to bag then tog will increase, so in test would be warmer,
i am still in the aguement of, you should carry a bag suitable for the conditions you are going into, liner or base layers excluded,
reasoning is clothes are emergency extras, not to be used allt he time as if sh@t does hit the fan you have extras to rely on,
personnaly if you wear to much clothing in the sleeping bag then no heat is released into bag so you are only being insulated by clothing,
dont know if point has been made, sleeping bags trap warm air to insulate you, if you dont give the bag warm air it wont be that good
i am still in the aguement of, you should carry a bag suitable for the conditions you are going into, liner or base layers excluded,
reasoning is clothes are emergency extras, not to be used allt he time as if sh@t does hit the fan you have extras to rely on,
personnaly if you wear to much clothing in the sleeping bag then no heat is released into bag so you are only being insulated by clothing,
dont know if point has been made, sleeping bags trap warm air to insulate you, if you dont give the bag warm air it wont be that good
In reply to Alpnick:
So the conclusion of all this argueing seems to be,
best warmth to weight is gained by sleeping naked in a suitable bag.
extreme temp rating can be improved by wearing clothes i.e. you live until your core temp reaches a given point (i think this is 27C) and clothes will help stop this temp being reached.
what we do not agree on is sleeping naked improves your comfort rating i.e. the temp at which you can get a comfortable and uniterupted nights sleep (a night is defined as 6 hours).
its obvious that a number of people on here feel there temp rating is improved by sleeping naked so for them it is improved (being a subjective figure) and others feel clothes increase their comfort rating so for them clothes do (again as its subjective) so no amount of research will ever prove it more than that.
Take a suitable sleeping bag and do whatever you find comfortable - end of thread!
p.s. liners add warmth but none of us can remember figures! now i really need to do some work
So the conclusion of all this argueing seems to be,
best warmth to weight is gained by sleeping naked in a suitable bag.
extreme temp rating can be improved by wearing clothes i.e. you live until your core temp reaches a given point (i think this is 27C) and clothes will help stop this temp being reached.
what we do not agree on is sleeping naked improves your comfort rating i.e. the temp at which you can get a comfortable and uniterupted nights sleep (a night is defined as 6 hours).
its obvious that a number of people on here feel there temp rating is improved by sleeping naked so for them it is improved (being a subjective figure) and others feel clothes increase their comfort rating so for them clothes do (again as its subjective) so no amount of research will ever prove it more than that.
Take a suitable sleeping bag and do whatever you find comfortable - end of thread!
p.s. liners add warmth but none of us can remember figures! now i really need to do some work
In reply to epik: you work.. click a few buttons isnt hard!
sorry, is this the end of thread now
not like me to want the final say!
sorry, is this the end of thread now
not like me to want the final say!
In reply to gear boy: i will have the final say : 0 )
In reply to man_in_the_alps: no you wont
In reply to Judderman: are you sure
In reply to Judderman:
rubbish
rubbish
In reply to Judderman: i'm not
In reply to man_in_the_alps: double rubbish
In reply to gear boy: whatever
This is very childish. I suggest we all grow up and stop posting on this thread right now.
In reply to Judderman: yes i agree
In reply to gear boy: I agree too,bye
In reply to man_in_the_alps: bye
In reply to Alasdair Fulton: I use a silk liner regularly and do think it makes a difference. I'm not convinced that it adds a season though. One bonus is it's a lot easier and cheaper to clean (washing machine) than a down bag.
Alistair
Alistair
In reply to Alasdair Fulton: i sell a lot of liners to people who go travelling, and from the people who make the bags a silk liner should give you an extra 5 degrees! But bear in mind do you sleep nude, in a tent, with someone else, do you fell the cold?? so its hard to say exactly but it a guide!
Oh god, it's started again. Just as the thread was petering out there's a resurgence of debate. There's probably a moral in here somewhere...
In reply to Alasdair Fulton:
I used a silk liner on the KIMM a couple of years ago when the temperature hit -5 and my sleeping bag was rated to +3. Slept like a log. Worked fine on a trip to Everest as well (although with a different sleeping bag).
I reckon the big difference is the elimination of cold spots when you roll over and compress a section of the bag that was exposed. Well worth the money
I used a silk liner on the KIMM a couple of years ago when the temperature hit -5 and my sleeping bag was rated to +3. Slept like a log. Worked fine on a trip to Everest as well (although with a different sleeping bag).
I reckon the big difference is the elimination of cold spots when you roll over and compress a section of the bag that was exposed. Well worth the money
In reply to Alasdair Fulton:
Right. I think everything has been said that can be on this subject, so no more posts.
Right. I think everything has been said that can be on this subject, so no more posts.
oh btw, I ordered one for £20 from New Zealand:
http://www.nznature.co.nz/mshop/spi//5_SIL_851
Hoping it'll be fine but no way to tell for sure and it's a bit far to return it. Got it in green but they say they won't be getting that colour in till the 12th so will have to wait a while.
In reply to epik:
why thank you !-)
> (In reply to gear boy)
>
> petty, very petty with a hint of sad!
>
> petty, very petty with a hint of sad!
why thank you !-)
In reply to jo_willett:
This is a first - a post like that and still the thread carried on regardless.
Some people just get too excited about gear.
Ben B
> my black silk liner definitely makes me appreciably warmer ... the only item of clothing I usually wear inside is a pair of warm socks
This is a first - a post like that and still the thread carried on regardless.
Some people just get too excited about gear.
Ben B
In reply to Alasdair Fulton: Sleeping bags in sleeping bags is often very inneffective as all those layers of fabric create condensation problems, and the insulation of the inner bag is crushed by the outer bag. That is why insulation ratings for bags don't increase at them same pace as weight. Silk liners are fairly warm in their own right, very comfortable and easy to clean. Fleece liners are all of the above and warmer. Light wieight option is to wear all your clothes except your shell inside the bag. Finaly anything with a comfort rating of -5 from a reputable company combined with clothing is sufficent for MOST nights scottish winter nights and will probably stop you actually being in danger on other nights (though you might not get much sleep).
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