Winter wildcamping - what I need to know?

[mountainm]

The problem with that theory is that you lay on half the sleeping bag, thereby squashing all the fibres. To compensate for this we use a sleeping mat to add extra insulation, which everyone agrees is a top idea. When we suggest adding extra insulation to the top of the system, by way of extra clothes, we have posters suggesting the whole thing effectively becomes a fridge! It doesn't of course.

If you are wearing appropriate wicking type underwear, you would never generate enough sweat to cause a moisture problem, unless you were doing something very "vigorous" inside the bag. Just laying there asleep would not cause a problem.

If anyone doesn't believe us try this:

Experiment
1x wool thermal type glove
1x pair of Ski mittens
2x freezer bags
2x thermometers
1x bucket of ice water.

On one hand put on glove, slip thermometer into glove and put on mittens, put other thermometer into remaining mitten then put on freezer bags. Dunk hands (encased in mittens and bags) into Ice water. At 30 second intervals record temperature next to hand. Stop when you are bored.

One hand represents sleeping bag, no clothes
the other represents sleeping bag with clothes.

let us know what you find.

 

[Wayland]

The problem with that theory is that you lay on half the sleeping bag, thereby squashing all the fibres. To compensate for this we use a sleeping mat to add extra insulation, which everyone agrees is a top idea. When we suggest adding extra insulation to the top of the system, by way of extra clothes, we have posters suggesting the whole thing effectively becomes a fridge! It doesn't of course.

If you are wearing appropriate wicking type underwear, you would never generate enough sweat to cause a moisture problem, unless you were doing something very "vigorous" inside the bag. Just laying there asleep would not cause a problem.

I'm sorry, I thought I was writing for people that could spot the blooming obvious but just in case I'll add, "A sleeping mat of some kind is essential."

As for moisture production, about a pint of liquid is lost per day through simple human transpiration when stationary, that's 1/2 a pint of moisture that is released inside your sleeping bag every night. If you are overheated, that amount increases dramatically even with out activity.

Some of that moisture escapes the system but some does not and on a multi night trip it will accumulate if the bag is not effectively dried in between.

This matter is not as straight forward as either side of this argument would like to believe, that is why it has been debated, ad nauseum, for so long. For the sake of people who want to read an interesting thread without listening to a squabble over details I was trying to simplify matters a little.

I'll reiterate the important part shall I?... Both systems have merits.

.

 

[HillBill]

How on earth does a freezer bag come remotely close to representing a sleeping bag?

So how do u explain the fact that some are hotter with less on? It's not just me, look about on the net, do a google search, there are lots of discussions on other outdoor forums about the subject. I read some last night. There seems to be equal numbers for both arguments. By the sounds of it you haven't tried it, if so then how can u possibly say it's not true?

 

[Wayland]

 

[mountainm]

How on earth does a freezer bag come remotely close to representing a sleeping bag?

So how do u explain the fact that some are hotter with less on? It's not just me, look about on the net, do a google search, there are lots of discussions on other outdoor forums about the subject. I read some last night. There seems to be equal numbers for both arguments. By the sounds of it you haven't tried it, if so then how can u possibly say it's not true?

The freezer bag is to stop your mittens getting wet, the mitten is the sleeping bag, the glove is the clothing. It's all about compression - I have covered this off in my previous posts.

 

[toilet digger]

 

[mountainm]

And I have tried it.

 

[treadlightly]

Most of the time if I put on extra clothes which wick moisture or stay warm when damp (ie wool) then get inside my sleeping bag I will be warmer than if I hadn't done so. Surely no one will disagree with that?? :swordfigh

 

[toilet digger]

And I have tried it.

 

[Paul_B]

I think I posted the same sort of argument as Wayland did (slightly better than me) on the first page of posts just after the take clothes off makes you warmer post. Both ideas can happen but with different factors being involved. One idea assumes it is the taking of clothes off that is making you warm when it is the liberating of space for the infill of the sleeping bag to fully loft thus allowing it's full insulation capabilities to be in effect. The other argument is assuming that there is sufficient space inside the bag to take the occupant and his/her extra clothes. Both arguments assume adequate mat insulation underneath. The people on both sides of the argument feel warm with their solution which is all that really matters. As for me all I am looking for now is any advice as to how I can keep my hands warm and dextrous when the rest of me does not feel the cold. I can be sweating with all my layers on and my hands are numb or tingling. It is only because of the last two years I developed Reynauds all of a sudden.

BTW I could dig out some formulaes for multi layer insulation systems so you can input your own figures into it to prove that IF all layers are working at their most efficient loft then more layers (such as clothes inside the sleeping bag) will only help with the insulation of you. I work in the thermal insulation sector working on power stations and other industrial plants. It is my way of making a living and if I didn't accept the current scientific knowledge concerning thermal conductivity I would not have the living I currently have. IIRC British Glass used to have a really good multi layer conductivity online calculator. It allowed you to put in different layers of materials with different thermal conductivity values (varies with average temp), different thicknesses, different shapes (rectangular is different to cylindrical), etc. Was pretty good really. I don;t think it is still available and I don;t have access to it anymore as we are not members of BG anymore (a trade body for glass, glass fibre and other ceramic or vitreous materials).

If it helps to think of it, heat loss is like something rolling down a hill. high temp is at the top, low at the bottom and the steeper the hill the faster the heat is lost. The insulation is like changing the air to water or to custard (viscosity increasing). Down is like custard a thin vest is like water. Also adding more layers is adding more layers of water or custard or syrup, it just slows the rolling object down. If you compress the down it is like reducing the thickness of the custard so the object takes less time to get through it as it is thinner.

Sorry if the above is patronising or simplistic I am not trying to be patronising just trying to give a simple analogy (which is not totally accurate but can help I reckon). I say once again insulation is my business and there are power stations all over that are saving a lot due to the science I apply daily to my work and I am attempting to put down here.

My only problem now after the good advice above on cold weather camping is hands. I am interested in cold sinks and how the location of pitch can make a huge difference in camping comfort. Anyone got an idea on that.

 

[Wayland]

I use a combination of thin single layer fleece gloves from Decathlon inside German Army Bag Mittens from Endicotts.

It means I can slip the mitts off if I need dexterity to use a camera or such like but have the warmth of the mittens for general use.

I take a spare pair of mitts and a couple of spare sets of the inner gloves to change when damp.

As for cold sinks, one of the very noticeable things about properly built snow shelters is that the entrance should be below the sleeping area. I try to apply the same principle if I'm camping out in Winter, try not to be at the lowest point wherever you are, not just for cold but also water too.

Part way up a slope is often better than at the bottom but of course it's best if you have shelter from the wind so compromise is usually the name of the game.

If you are expecting fresh snow or even drift it will tend to accumulate most in the lee of shelter so that can become an issue too.

 

[Ch@rlie]

A previous lesson learned while fishing in winter, Make sure you fill your kettle (or pot in which you boil your water) before you go to bed, "IF" it freezes its in the correct container to be heated to get that all important first hot drink of the day.
If your using gas as fuel type make sure you keep the canister in the sleeping bag with you over night, as even the winter mix gas gives poor performance if its too cold.
regards the sleeping bag and clothes on or off argument, what works for some don't work for others. The simplest rule to follow is "do what works for you"

 

[Maggot]

If you are going to treat someone with hyopthermia, you will strip off any wet clothing, then dry them and then re-dress them with whatever is dry and to hand, before getting in the sleeping bag with them to re-warm them. You wouldn't strip them, and then slip in the sleeping bag in their pants as it will get them warmer quicker would you?

So, if the inference there is that they will be warmer when dressed and put in a bag, why would it be that if you didn't have hypothermia you would be colder if dressed and in a bag?

 

[sasquatch]

Oh dear...I've done a lot of winter camping over the years and have tried all sorts with different results. I tend to strip down to thermal underwear and get in my bag for a good night's sleep. Too many clothes and I'm cold. On the other hand, I've tried a warm drink and star jumps before bedding down in my pants and vest in -14. I was boiling until I woke up freezing 2 hours later as a result of sweating. As Wayland said, there's merits in both. Surely we should all do what works for us and not get too uptight about others having an opinion or system that works for them?

 

[Nonsuch]

Good - back on topic instead of Tom and Jerry!

 

[sasquatch]

Good - back on topic instead of Tom and Jerry!

Back on topic, good idea!

Headwear when sleeping for me. Fingered thinsulate gloves with folding mitten on them, about £4 from the market 12 years ago and nice and toasty for my digits. A wool army issue buff when the temp drops, I wouldn't be without it! A log under my feet when sat still to avoid cold toes. Fresh socks before bed and a hot drink. A fire when possible does wonders...

 

[EdS]

If you you are heading to the Lakes etc in the winter - it is unlikely to be a snowy winter wonderland. Mostly it will be p**sing down and blowing a gale.

As for the clothes v bag arguement. Too many clothes do stop the bag working correctly. a thin layer or 2 adn a decent bag is the way to go. Don't for get that more layers of clothing also trap more water vapour (sweat) and you do sweat even when cold. More moisture = more chilling or put another way less insulating. A decent bag on the other hand both insulates and is breathable allowing water vapour out.

 

[Wayland]

Complete tosh. <Snip

.........................

..............................

Well that's what happens to maggots like that I guess.

I do hope Redwall comes back though, he seemed a lot nicer.

 

[DaveBromley]

i was wondering how long it would take for Maggot to be banned lol ah well back to the discussion. 1I found it really counterintuative to strip down to be warmer but have tried it and found that it worked for me, not going to say that this approach is the right one for everyone but like i said it worked for me.

Give it a go and see if it works for you, if it doesnt then you will know

Dave

 

[demographic]

I tend to go camping out more in winter than in summer for some weird reason but I've had an expedition bag for donkeys years, a good kip mat is essential for me and a warm thinsulate lined hat keeps my head warm when its not fully in the bag.
Sometimes I've camped in caves, under tarps, and in a bivvy bag.
I hardly ever use a tent but that's just me, I like to see the stars on cold clear nights if I am in the open.
Headtorch is great.

Most of the time its not as if in the lakes you will be far from civilisation anyway.