UKC

Hi,

I'm looking for a new sleeping bag, and can't decide between Synthetic or down. I'm aware of all the usual arguments that down's lighter and packs smaller, but that Synthetic can get wet and is cheaper etc etc... but it doesn't really answer the question.

So, I've got a couple of options lined up, Down & Synthetic, and need to decide what to go for. What I think is going to tip the balance is the temperature ratings on them...Planning to use it for Scottish Winter bivvies and Summer Alpine Bivvies too...what kind of rating should I be looking for? would a -8 comfort temperature bag be ok, or should i be eering towards -15 or less?
Bear in mind that I'll most likely have some clothing on, the idea of getting Naked in Scotland doens't appeal for all sorts of reasons

Cheers for your advice & help

In reply to carrot_boy (North East Wales MC):

Why would you bivvy in the scottish winter?

In reply to neuromancer:

sadist!

In reply to carrot_boy (North East Wales MC): ahh...good to know you can always rely on UKC for helpfull advice

In reply to carrot_boy (North East Wales MC):
My sleeping bag is a Rab, it's discontinued but it's equiverlent to the Andes 800.
I have snowholed in the Alps, and used it in Bothys in scotland.
The only time I've been cold in it once, which was between Xmas and new year in the Huchinson's Memorial Hut. (like a Pr@t I was using my down coat as a pillow)

If you are planning of climbing with a rucksack, then the packsize of a sleeping bag will be important, as you will want to reduce the size of your pack.

In addition a synthetic sleeping bag degrade over time as the hollowfibre degrades, where as down doesn't.

BTW when I bought my bag about 24 years ago it cost me £220, which was alot of money, however if you compare it to it's life, it's less than £10 a year. (I have been out of walking and climbing over the last 10 years but still it makes it very cost effective)

good luck with your choice

In reply to peas65:

I think you mean Masocist!
no sadist

In reply to carrot_boy (North East Wales MC):

In my experience of wild camping in Scotland (inside a tent), I've always been pretty comfortable wrapped up tight in my old Rab Atlas 1000 bag rated to about -15. I'd normally only wear a thermal top inside.

I've toyed with the idea of replacing it with a lighter bag, and I think that with more clothing on I could probably get away with a lower rated bag reasonably comfortably. I've certainly managed to go down to somewhere around freezing point in a bag rated as +5 at the extreme and a friend of mine has used a summerweight bag in winter in Scotland with all clothes on, and seemed ok, although it probably wasn't much below freezing (-5?) that night.

In reply to carrot_boy (North East Wales MC): If the rating is the EN 13537 standard I think you can trust it and use it to compare different bags very fairly. Testing a couple of bags for UKC I've found I can sleep comfortably in them at the lower limit wearing a base layer, light hat and warm socks. It's a really good thing that more firms are using the standard because even if you find your level is more towards the 'comfort' figure than the 'lower' figure, at least it's consistent between brands.

http://en.wikipedia.org/wiki/EN_13537

-8 Comfort sounds plenty for Scotland, as that means the lower limit will be in the mid teens.

In reply to Richard Phelan:


Yep, that's a very good point. My ME lightline is 12 years old and still works just fine. Down bags are something you can really consider as a good investment over the long term.

-8 comfort might not feel very toasty in a night up a mountain in a scottish winter, unless maybe you got a big spacious bag you could get in with your puffy insulation layers on. I've just got myself a -15 rated down bag cos I'm a big softy... a synthetic bag plausibly rated to the same temperature would be a bit hefty by comparison

Have you considered something like the PHD synethtic combi bag, incidentally? http://www.phdesigns.co.uk/product_info.php?cat=79&products_id=261

In reply to carrot_boy (North East Wales MC):

I slept in an Alpkit Skyehigh 800 for a total of two months in Scotland, including plenty of winter nights up top.

It's limit is -10.

That said, there are obviously occasions where I'll stick on base layers and a light belay jacket too.

In reply to CurlyStevo:

I had not realised the lows of the tops (so to speak) was only -10.

I suppose it always feels colder up top when you're stood in the wind, faffing about trying to pitch a tent at 4pm though, tired and hungry and cursing yourself for deciding not to go to the Clachaig

I remember having a high bivvy this year in summer, running out of water and literally being able to see the Clachaig from where we were perched (and parched). It was torture!

In reply to professionalwreckhead:
"Scotland, including plenty of winter nights up top."

temperature wise it's colder in the glens. It doesn't really get colder than -15 at munro level and very very rarely (>10 years?) below -10, however the glens can get lower than -20 (OK rarely but it does happen and has happened quite a few times in the last 10 years).

In reply to professionalwreckhead:

here's the info for the caringorm AWS http://cairngormweather.eps.hw.ac.uk/archive.htm

Winter 2009 / 2010 it was -20 and lower for quite a few nights in aviemore, but the AWS wasn't getting lower than -9. The cold air sinks at night.

In reply to CurlyStevo:

Thanks, that's useful.

Is that also the same reason as why the lowest temps in the glens can occur after sunrise? e.g. cold air continually moving down and the ground having given up the last bit of heat it retained from the previous day?

I've noticed quite a few times that the temp through the night has been higher than at 9am.

In reply to professionalwreckhead:
Can't help there, I would assume the coldest temps would be around dawn.

In reply to professionalwreckhead:
I know it's often less windy at dawn and dusk, something to do with the way air moves to and from the land and sea. This could allow more cold air to drop from the mountains?

In reply to CurlyStevo:

I can feel myself about to become rather unproductive at work as I start google researching basic thermodynamics!

In reply to professionalwreckhead:
report back your findings, I'm trying to work