Western Mountaineering temperature rating

[deejayen]

I've got a Summerlite sleeping bag which apparently has 255g of down, and Western Mountaineering rate it to 0 degrees celsius.

Is it possible to relate this to the EN13537 ratings?

I'm looking to buy a new sleeping bag, and it would be helpful to compare them against the Summerlite.

 

[Jww]

which down?

i was tould roughly to multiple 255g of 800 fill

 

[cathyjc]

WM quote the "loft" of the bag (both layers). If you can measure/get the loft on whatever it is you want to compare ?

I prefer to use loft as a tool to gauge how warm a bag is "for me". As a cold sleeping female the EN 13537 rating just don't work.

 

[deejayen]

Thanks!

They say the loft is 10cm. 850+ fill power down which is possibly a bit fluffier than the spec. However, I'm looking to (probably) buy a synthetic bag.

I think I'm a cold sleeper. I tried the sleeping bag in 3 or 4 degrees and was too cold - I was okay at that temperature when I slept in a Buffalo lightweight bag inside the Summerlite.

 

[grattygruff]

I was researching various sleeping bags recently and I’m sure I read the Western Mountaineering (and many US companies) quote the “limit” rating rather than the “comfort” rating in their specs

 

[deejayen]

Actually, I've just seen that WM have a table in their FAQ's and have tested the Summerlite to EN13537:-

T Comfort: 5C
T Limit: 0C
T Extreme: -15C
WM Rating: 0C

It looks like it's a 5C (max) bag for me, so I'll need a new bag which is rated a bit warmer than that. I'm not sure, but maybe a T Comfort rating of between -5C and 0C.

 

[cathyjc]

Thanks!

They say the loft is 10cm. 850+ fill power down which is possibly a bit fluffier than the spec. However, I'm looking to (probably) buy a synthetic bag.

I think I'm a cold sleeper. I tried the sleeping bag in 3 or 4 degrees and was too cold - I was okay at that temperature when I slept in a Buffalo lightweight bag inside the Summerlite.

I wouldn't use my Summerlite at 3/4 C either. I'd probably need temps to be 10c or over to be comfortable. As they quote - females sleep 10c colder than males ......

A synthetic bag is never going to "cut it" for me - unless I'm indoors .

 

[cathyjc]

Actually, I've just seen that WM have a table in their FAQ's and have tested the Summerlite to EN13537:-

T Comfort: 5C
T Limit: 0C
T Extreme: -15C
WM Rating: 0C

It looks like it's a 5C (max) bag for me, so I'll need a new bag which is rated a bit warmer than that. I'm not sure, but maybe a T Comfort rating of between -5C and 0C.

The temp. is never going to be steady at one number over several days or even one night so it's best to plan a good margin of error and take something that gives you more warmth than the expected temp.

My next bag up is a WM Ultralite - which does me for most Scottish 3 season stuff down to 0c.
At the cooler ends of 3 season I got me the Versalite last year - super toasty.

 

[deejayen]

Thanks, Cathy. It's helpful to know what other cold sleepers use. The Ultralite might be a good option for down to freezing - it's just more expensive than I'm looking to spend at the minute. I'm also not too sure about the cut of my Summerlite for a side sleeper, and I don't find the hood arrangement to be very comfortable - the Summerlite would be better for me if it had a draft collar.

 

[cathyjc]

Thanks, Cathy. It's helpful to know what other cold sleepers use. The Ultralite might be a good option for down to freezing - it's just more expensive than I'm looking to spend at the minute. I'm also not too sure about the cut of my Summerlite for a side sleeper, and I don't find the hood arrangement to be very comfortable - the Summerlite would be better for me if it had a draft collar.

In the conditions I use my Summerlite a draft collar and hood are really not needed - and I'll probably wear a hat to keep the Scottish 'all night' summer light out .....

I have an Astralite (+extra fill) quilt on order to see if that is a better warm weather option ???
I've not used a quilt so far. If I don't get on with it I can sell and won't loose too much ££'s.

PS. It has taken me years to accumulate these and I know I'm lucky to be able to afford this expensive kit.

 

[cathyjc]

Don't know how tall you are but this is a good deal for a 'shortie'

https://www.ebay.co.uk/itm/205106839999?

 

[deejayen]

In the conditions I use my Summerlite a draft collar and hood are really not needed - and I'll probably wear a hat to keep the Scottish 'all night' summer light out .....

Yes, I bought the Summerlite for summer bike touring here in northern Scotland, and thought I could supplement it with a down jacket or vest if the temperature dropped into single digits. It was just wishful thinking (based on the 0C rating) that I could get away with using it at 3 or 4C.

 

[deejayen]

Don't know how tall you are but this is a good deal for a 'shortie'

https://www.ebay.co.uk/itm/205106839999?

Thanks, Cathy, but I'm 6', so it would be too small for me.

 

[cathyjc]

An Astralite sized to go over the Summerlite would be ideal for you but the supply (and cost) is probably an issue.

I ended up ordering direct from WM as I wanted the extra fill. I Had to use a VPN and ship to Stackry as they don't ship to UK.
Elite Mountain Equipment stock WM and are flexible enough that they would probably order an item specially if they thought they had a guaranteed sale.

 

[deejayen]

Thanks, Cathy - that's helpful.

I've thought a quilt might be worth trying (I was considering a Katabatic a while ago) so the Astralite is an interesting option...

 

[cathyjc]

Thanks, Cathy - that's helpful.

I've thought a quilt might be worth trying (I was considering a Katabatic a while ago) so the Astralite is an interesting option...

@edh likes his and I respect his opinion. I know he sleeps cold.

I also have a good deal of faith In WM sleeping gear - having tried a load of bags from other manufacturers and found a lot to be "wanting".
So it's up to me whether I get on with it or not......

 

[deejayen]

Yes, the quality of the WM seems much better than a lot of other bags - the Summerlite lofts amazingly well.

Does edh have the Astralite?

 

[el manana]

I have a Summerlite and sleep cold, i tend to follow Womens comfort ratings. My general plan is to use it when temperatures remain above 0C then if below switch to a 450, then a 600 bag.

I used it recently when in-tent dropped to 4C overnight wearing Alpha base layers. I wasn't cold but I wasn't warm either, a little bit uncomfortable but I couldn't have been that bothered as I didn't reach for my down jacket nearby. Pulling in the draw cord helped.

Last time I went out overnight temps were 9C, I was toast.

 

[cathyjc]

Yes, the quality of the WM seems much better than a lot of other bags - the Summerlite lofts amazingly well.

Does edh have the Astralite?

Ed - yes. he posted recently that he likes it.
WM specialize in down sleeping gear - it's their niche.
Other (but not all) manufacturers make multiple types of gear - to me that translates as not concentrating on 'anything' in particular .....

 

[old-skool-lite]

Other (but not all) manufacturers make multiple types of gear - to me that translates as not concentrating on 'anything' in particular .....

Oh dear & a 5 dot ellipsis to boot!

 

[edh]

I'm a cautious fan of the Astralite; I've only used it probably 25 nights hence the cautiousness....
For me it easily goes a fair way below zero. I find just using one (the lower) strap with it suits my largely side sleeping habit.

Edit: I've got the Ultralite too.

 

[cathyjc]

I'm a cautious fan of the Astralite; I've only used it probably 25 nights hence the cautiousness....
For me it easily goes a fair way below zero. I find just using one (the lower) strap with it suits my largely side sleeping habit.

Edit: I've got the Ultralite too.

Thanks for the extra info.

 

[Lyrrad]

Is the Ultralite a regular width bag? I have a Montbell super spiral bag which is incredibly comfortable and I am a side sleeper. As Ive got older my tolerance of the cold has slowly started to diminish and the Ultralite would make sense from a warmth perspective but I'm unsure about the width

 

[mjh]

I’ve got an Astralite as well which I reckon does me down to about zero (albeit with a woolly hat and sometimes the need to put on a warm jacket or on top of the quilt when it is getting towards zero).

 

[tja]

They have the Terralite for side sleepers, as the blurb says:

”The ultimate side-sleeper bag; the TerraLite combines a luxurious amount of internal space with a three-season bag that still weighs less than two pounds. Designed with a semi-rectangular shape and using the lightest weight materials, this versatile bag is the pinnacle of comfort and design.”