Wool/cotton long johns insulation when wet

  • Hey Guest, Early bird pricing on the Summer Moot (29th July - 10th August) available until April 6th, we'd love you to come. PLEASE CLICK HERE to early bird price and get more information.

Andy BB

Full Member
Apr 19, 2010
3,290
1
Hampshire
Getting your bag wet on the outside is one thing but getting a flood inside it is just poor admin. I take your point though and i hope nobody dies :)

i will leave it there as i have digressed somewhat.

Andy, let me know how the test goes and give me contact details for your wife so i can paw over your kit when you are gone :D

You sound just like my colleagues on the last Norway trip, who were so certain an old knackered fogey like me was guaranteed to die that they had already divvied up my kit in advance:) (You know who you are, you ghouls!)

You're right of course - if one is properly prepared, you should not get water inside a sleeping bag. However, I did when my hot water bottle burst - and how many recommend some form of hot water bottle in low-temp camping? And during the day one tends to open up a sleeping bag to let it air, and if your tent goes down in bad weather (torn-out seams from over-stressed guy-lines, rips from collapsed poles etc) - you can see where I'm going!

And not all synthetic sleeping bags are the same. Quilting stitch lines, for example, not only create cold spots, but an entry-point for water ingress, no matter how good the outer layer on the bag is.

I admit I am biased against down in low-temps, despite still owning a few, partly because of my experience mentioned before. Once wet - for whatever reason - you're stuffed, and the colder it is, the more danger you're consequently in. However, there's no denying they are warm and cosy when dry, and lighter than synthetic stuff. As with everything else, its a matter of personal choice and risk assessment.
 

rg598

Native
Since the topic has shifted to synthetic vs. down sleeping bags, while it is true that synthetic insulation retains its insulation better when completely wet than down, I find that it is one of those things that makes a difference only on paper. If you have a -20C bag and it is -20C outside, and you then proceed to get that bag wet, you will die. The fact that a down bag loses 80% of its insulation while a synthetic bag loses 60% of its insulation will do you little good (numbers are made up). It is the same issue as with all the "materials" debates. If you are thermally neutral i.e. you are not overdressed or are not using a -20C bag in +20C weather, then if you get wet, you are in trouble. There is no clothing that will keep you warm when wet, and there is no sleeping bag that will do that either.

As far as drying clothing in your sleeping bag, you can do it with either down or synthetic bags.

Synthetic insulation degrades more slowly from moisture than down, so one has to do the math in terms of weight saved vs. how often the bag has to be dried to retain its temperature rating.
 

Uilleachan

Full Member
Aug 14, 2013
585
5
Northwest Scotland
It's not about keeping you warm when wet, it's about stopping further heat loss once wet, key to that is shelter from the elements, buildings natural features tents tarps wind breaks and bivvy bags etc, achieve some effective shelter stave off further heat loss and even wet insulation/clothing will allow heat to slowly build, provided those wee mitochondria have enough fuel to keep the cellular motors running.
 

Toddy

Mod
Mod
Jan 21, 2005
38,998
4,650
S. Lanarkshire
I have worked sodden wet, inside my outer clothing, for three solid weeks at a time; time after time in wet and in sub zero weather.
The trick is to stop the wind.
Stop it dead, live wet inside the windproof clothing and keep moving. If you stop for long you chill through, just keep moving until you can get somewhere in the sunshine out of the wind, where you can open up and air dry a bit, or somewhere you can strip off, vigorously towel yourself dry and get into dry (ish :rolleyes: ) kit.

It's the keep moving and stop the wind taking away any heat you can make, that lets you work and get on with things.

Wool's warmer inside those conditions than cotton (jeans were utterly miserable :( as were cotton bras and knickers. In the end we put wool thermals on and just forgot about the rest of the underpinnings ) polycotton trousers were fine under goretex though, and even the girls wearing the cheap peter storm unbreathable waterproofs found that.
We found that we could wear dry the wool and polycotton just by taking the waterproofs off and moving around in the bothy in the evening. They never got bone dry, but dry enough not to chill us. Socks too, though there was nothing we could do about saturated boots :( Just put them back on and wear them. Double wool socks though, and we weren't cold, so long as we kept moving. Tea breaks and lunch no longer than ten minutes kind of thing. Jeans we could never get dry enough not to be cold, clammy and 'hard'.

Our sleeping bags were kept in the bothy, and they were dry there, but cold, icily cold. We had a selection of everything from down to North Face -20, Ajungilak, etc., and the down won. It fluffed up and it stayed warm and it was warm quickly, unlike the others. A Mammot bag worked well too, but it was a mix, it was still better than the synthetics. With the sleeping bags though, a silk liner was brilliant, but the ones that were prelined with cotton were easier and more comfortable than the artificial fibre ones.....I got fed up tangling with it all when I was cold and tired and in the end sewed my silk liner into my bag.

I don't like wool and nylon type mixes for socks; the nylon degrades the wool too quickly I find, while pure wool thickens and felts as it shapes to your foot and boot.
I have since bought knitted silk thermals and they are brilliant :) they don't wear as well as the wool though, but as a fine underlayer they are ultimate.

There is no reason for merino thermals to be scratchy if they are genuinely made from merino. Adding nylon to the mix can make it coarse though, so check the quality/feel of them before you buy. Good thermals should be fine enough that if you de-layer then body heat dries them off.

Most of us don't need to work damp and wet. It's a choice for us, and an awful lot of the clothing sold for the purpose is fine for cold and dry; it's not so good in the persistant damp of an Atlantic climate.

Some of the stuff the sea fishermen wear is very good though, but they usually have a good heat somewhere to dry off if necessary. The old boats didn't, and they wore wool and oilskins.....so wool and total water and wind stop layers, and before they had oilskins they used oiled skins. MacAlpine came to the council dressed in fishskin cagoule made from tanned salmon skins....the others came in their finery hoping to be chosen.....guess who ended up king ? :)
The Inuit made their waterproofs out of seamammal intestines; fine, beautiful and lightweight, and wind and waterproof.
They carefully build in venting....open up the waist and neck and body heat alone dries off underneath clothing. We just do the same.

Goretex, TPC, evenk and so on are very, very good, and a world of difference compared to the solid waterproofs though, and they manage fine over almost anything.

In the persistant dry cold, then I think cotton would be fine, the Scandinavians, the Himalayans and the Mongols wear it, so it must work for them.
Thing is that cotton is cheap; cheap to produce and to spin and weave and knit by machine. It's even used inside quilts for warmth, but in a damp climate, find anything else but cotton for underneath if you're going to be either working hard and getting sweaty, or going to get soaked.

Merino doesn't need to be expensive either; both Aldi's and Lidl's have good merino rich thermals for sale through the year, and they have proved to be both comfortable and warm as well as relatively hard wearing.

At the end of the day, we're all different, our requirements are different, our activity levels are different.

Unless dry then cotton is cold and it's really hard to dry. Wool soaks up a lot of moisture and stays relatively warm, but unless heated from inside, it takes a long while to dry off.
Modern wick away fibres are very, very good, but they don't sell specialised fabric conditioners to get rid of the smell for no good reason. They are also not safe near fires and open flames....neither is cotton though. Wool is, so is linen.
Not a concern for most outdoors folks, but it is for those of us who do play with fire :)

Each to their own.

cheers,
Toddy
 

BCUK Shop

We have a a number of knives, T-Shirts and other items for sale.

SHOP HERE