Doubling up sleeping bags for winter?

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rjb
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Re: Doubling up sleeping bags for winter?

Post by rjb »

A very apt thread. I may be able to go without the CH a bit longer. :lol:
At the last count:- Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin X3, Raleigh 20 stowaway, 1965 Moulton deluxe, Falcon K2 MTB dropped bar tourer, Rudge Bi frame folder, Longstaff trike conversion on a Giant XTC 840 :D
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simonineaston
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Re: Doubling up sleeping bags for winter?

Post by simonineaston »

I'm not a religious person but I do thank the good lord above for closed cell foam...
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PH
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Re: Doubling up sleeping bags for winter?

Post by PH »

I don't do winter camping, it's not the cold I dislike but the long dark nights.
So, without the experience to know, I'm wondering if a quilt or blanket over the sleeping bag might be a better option. It would stop one bag being compressed by the other, all the additional insulation would be on top, you could probably moderate it better (Like just having it over your feet) and you could also wear it shawl like.
I like PJ's whatever the weather, for all the reasons already mentioned, plus if it turns colder than expected, they can be used as an additional base layer.
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pjclinch
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Re: Doubling up sleeping bags for winter?

Post by pjclinch »

boblo wrote: 28 Nov 2022, 10:23am If you've a bag that goes to -12°C, how much lower are you going? Occasionally it might get colder than this in Scotland or perhaps you're touring further afield?
While sleeping bag ratings are now tested to something more objective than whatever the marketing department reckon, it remains the case that different people feel warmer/colder in the same bag.
I used to have an ME Iceline rated somewhere south of -20 Comfort Temperature, and I eventually sold it on as the one night I managed to keep the zip done all the way up it was hitting -26 outside but mostly it was just too darn hot. I used to lend that bag to a "cold" pal who would use it fully zipped up in summer while I was a bit on the over-warm side with a Dewline, with less than 1/3 of the filling Comfort rated to 0.

My usual cold Go-To bag is an oldish ME Lightline with (IIRC) a -12 rating, and I've used it snow-holing in Norway when it got cold enough to freeze a bottle of juice solid, but the above pal would have found that bag not enough well above freezing.

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horizon
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Re: Doubling up sleeping bags for winter?

Post by horizon »

I used my Rab Ascent 700 down bag (slight mummy shape) last winter on a couple of short trips inside a roomy two season synthetic. I was very happy with the set-up. As others have pointed out, the issue is whether the inner bag can loft sufficiently. I was satisfied it could, just. Another bonus was I felt that the outer bag would keep the inner cleaner and drier in muddy inclement conditions - it just felt right. I would certainly recommend experimenting.
When the pestilence strikes from the East, go far and breathe the cold air deeply. Ignore the sage, stay not indoors. Ho Ri Zon 12th Century Chinese philosopher
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Sweep
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Re: Doubling up sleeping bags for winter?

Post by Sweep »

pjclinch wrote: 28 Nov 2022, 10:11am
Sweep wrote: 28 Nov 2022, 9:08am
By the by I always use separate sleeping gear - would not use for sitting around camp in.
Each to their own, but the main point of PJs camping is to stay warm & comfy and maybe keep the bag clean, and sitting around in a tent doesn't generate much in the way of sweat
agree - assumed you meant in camp/doing stuff.
In the tent (and may be there for a fair old time if a storm for instance) is essentially tent lounging sleeping stuff.
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Sweep
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Re: Doubling up sleeping bags for winter?

Post by Sweep »

boblo wrote: 28 Nov 2022, 10:23am

If you've a bag that goes to -12°C, how much lower are you going? Occasionally it might get colder than this in Scotland or perhaps you're touring further afield? Short days/very long nights in severe cold are not much fun. You'll spend most of your time in your bag(s), in your tent, on your back contemplating your navel as everything around you gets damper and damper. OK for one or two nights, not much fun for much more.
as i said I have no intention at all of being out in that sort of low temp. in fact pretty sure I have never experienced in my life, not even in a Moscow winter. But as I said am thinking ahead as am somewhat doubtful of the rating. Bag ratings are notoriously, er - insert word - and I have also read some reviews of the bag which question its rating.
My winter camping WILL be only for short periods - 3 days max, more likely 1 or 2 - but I would like to survive it or at least be in a fit state in the morning.
My comment on camp/sleep gear preferences was a general comment, not winter related.
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horizon
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Re: Doubling up sleeping bags for winter?

Post by horizon »

Sweep wrote: 28 Nov 2022, 2:00pm
boblo wrote: 28 Nov 2022, 10:23am

If you've a bag that goes to -12°C, how much lower are you going?
as i said I have no intention at all of being out in that sort of low temp.
Just another comment to say that on one of my trips (last December), it was so warm that of course the outer bag wasn't needed and even the inner (the Rab) was overkill. But then what if you really aren't sure? You don't want to take a Himalayan bag and get too warm but don't want to wake up at 3.00 am freezing. The great thing about your idea, Sweep, is that it's flexible, especially if an unexpectedly clear night dropped the temp right down. At the worst, you have a comfy layer of insulation under you and a cosier tent.

PS Just to say that I agree it doesn't have to be an epic journey of exploration across the steppes of Russia: one night on the north Downs in the middle of winter really shakes up the season and gets rid of winter blues!
When the pestilence strikes from the East, go far and breathe the cold air deeply. Ignore the sage, stay not indoors. Ho Ri Zon 12th Century Chinese philosopher
boblo
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Re: Doubling up sleeping bags for winter?

Post by boblo »

For reference, the ME Lightline as mentioned up there ^ used to be the benchmark 1kg down bag good for a real world ~-7°C. Other good quality 1kg down bags will be similar. Assuming a good mat, a silk liner, a hat and decent long johns/base layer, you'll be good for a couple of degrees more (less if you see what I mean...).

Obviously different people need different amounts of insulation and ability to cope with cold also depends on what you've eaten/drunk and what you've been up to immediately before turning in (amongst other things...).

Having camped in proper cold conditions, minus 10ish is probably as far as you'd want to go before it all gets a bit too 'type 2'. Camping in proper winter conditions for more than the occasional night is just not much fun. These days, I'd rather a Premier Inn and my bag collection includes an ME Redline, ME Iceline, 2x PHD Minims and a PHD Hispar. That's some very serious kit.
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pjclinch
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Re: Doubling up sleeping bags for winter?

Post by pjclinch »

Sweep wrote: 28 Nov 2022, 2:00pm
as i said I have no intention at all of being out in that sort of low temp. in fact pretty sure I have never experienced in my life, not even in a Moscow winter. But as I said am thinking ahead as am somewhat doubtful of the rating. Bag ratings are notoriously, er - insert word - and I have also read some reviews of the bag which question its rating.
This certainly used to be the case, with no formal testing system and ratings being very much the whim of marketing departments. But for quite a while now serious bags have gone through a formal and quite objective test, see https://www.thermarest.com/blog/en-iso- ... g-ratings/.
As I noted above, a cold sleeper can still feel cold in a bag at or well above its comfort rated temperature, but it's no longer the case that you'd take Brand X ratings with a pinch of salt compared to Brand Y. If you buy a bag rated with the EN 13537 Standard and it says -10 comfort then it will be (given suitable mat and fitting reasonably) much as comfy as some other bag rated the same.
Sweep wrote: 28 Nov 2022, 2:00pmMy winter camping WILL be only for short periods - 3 days max, more likely 1 or 2 - but I would like to survive it or at least be in a fit state in the morning.
My ridiculously over-hot bag was bought as a reaction to a night at south of -10 outside in a 3-4 season bag, and it was horrible. But at the end of the day (even though it never seemed to end!) I just had an uncomfortable night, nothing approaching hypothermia and I was basically okay (aside from tired) once I had some breakfast in me and had got going. The problem with "just in case" gear is you have to carry it, and if I'd carried my Lightline "just in case" rather than my Dewline when I think the Dewline will be fine it would have impacted on the walking/riding: more work, more tired, less fun. So as often it's a case of you choose, you lose...

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iandusud
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Re: Doubling up sleeping bags for winter?

Post by iandusud »

We have found these reflective foam mats to make a huge difference under our sleeping mats. They weigh next to nothing and cost next to nothing (100g I think). https://highlander-outdoor.com/uk_shop/ ... g-mat.html
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Re: Doubling up sleeping bags for winter?

Post by Pebble »

iandusud wrote: 29 Nov 2022, 9:00am We have found these reflective foam mats to make a huge difference under our sleeping mats. They weigh next to nothing and cost next to nothing (100g I think). https://highlander-outdoor.com/uk_shop/ ... g-mat.html
how big a difference ? 2 season bag down to -20 sort of thing
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Re: Doubling up sleeping bags for winter?

Post by boblo »

I've been using Neoairs now for ~10 years or so - or for as long as they've been available.

Much comfier than closed cell and lighter/less bulky than a normal Thermarest. Not sure of the R value vs closed cell but I'm never likely to go back to Karrimats having seen the (inflatable) light initially with standard Thermarests then Neoairs.

We used to double up with Karrimats in proper winter conditions in the olden days but they're massively bulky, are hard to stash within your pack/panniers and wick water enthusiastically. This leads to more dampness inside the tent as they're difficult to dry.

Just don't puncture an air mattress or have the means to fix it.
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Re: Doubling up sleeping bags for winter?

Post by iandusud »

Pebble wrote: 29 Nov 2022, 9:10am
iandusud wrote: 29 Nov 2022, 9:00am We have found these reflective foam mats to make a huge difference under our sleeping mats. They weigh next to nothing and cost next to nothing (100g I think). https://highlander-outdoor.com/uk_shop/ ... g-mat.html
how big a difference ? 2 season bag down to -20 sort of thing
Very difficult to quantify. What I would say is that for the cost and weight it's a no brainer. I would see their use as part of an overall strategy. A bit like a layering system for clothing if you get my drift.
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Sweep
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Re: Doubling up sleeping bags for winter?

Post by Sweep »

horizon wrote: 28 Nov 2022, 2:12pm
PS Just to say that I agree it doesn't have to be an epic journey of exploration across the steppes of Russia: one night on the north Downs in the middle of winter really shakes up the season and gets rid of winter blues!
agree. My winter expeditions will be short and sweet. No ambitions to cycle for a week across permafrost.
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