Sleeping Bag Ratings vs Real Experience ?

[Hypnagog]

I know there are a million threads about various sleeping bags, but I was interested in gathering together people's experiences of sleeping bag ratings compared to the manufacturer's specs.

Part of my reason for asking is that I'm due out next weekend (ground dwelling) and the temp is tipped to reach -3ºC overnight. I'm torn between taking my Snugpack Elite 5 (-15ºC comfort) or Snugpak 9 Hawk (-5ºC comfort) with a Thermolite liner thingy.

I slept out in -4ºC a while ago, but that was in a Snugpak Antarctica RE which is pretty much overkill for that temp as it has a comfort rating of -20ºC and an extreme of -50ºC with a weight and bulk that you'd expect! To be honest, I had to open the bag a little to cool down during the night.

So looking to travel lighter, I was wondering how close to the ratings people take their bags.

 

[Goatboy]

Years of selling and using the things has taught me anyway that ratings are pretty subjective. How warm you feel is down to many varying factors, How big you are (weight and height, a larger body retains more heat), what you've been doing that day (are you exhausted), what you've been eating, is it damp, insulation from the ground, (the more a filling can be compressed the better a mat you'll need under you), how the bags been stored (does it still loft properly), and are you warm before you get in? A bag only traps warmth that's given off, if you are cold and exhausted getting in your body has already shifted circulation away from extremities to protect your core. You aren't radiating heat the same and the bag cant trap it. You'll feel cold for a long time. So before you turn in, have a sugary drink or food, do press-up, run around the tent - basically warm up and then get in. Also there's nothing wrong with using a hotwater bottle of some kind - whether it's a traditional rubber one or some of your kit to like a Nalgene with hot water in it, it'll pre-heat the bag and make you more comfortable. There's nothing wrong or sissy about it, it's done on big expeditions believe me.

The bags are tested by having (usually) a tank of water placed in them in a controlled environment and the cool rate measured. But us humans aren't standard things, so as well as all the aforementioned things some folk are just cold or hot sleepers.

Hope this helps a bit?

GB.

 

[ozzy1977]

Ratings are more of a guide line, I have 2 identical coleman bags bought at the same time and they perform differently but bothe are nowhere near there stated rating, for me anyway yet the wife finds them fine.

 

[Shewie]

I've used the Elite 4 well into the minuses, -12 on the deck with a standard Thermarest 3/4, and -9 in the hammock with a Snugpak underblanket. I sleep in 200g Woolpower top and bottoms and I'm on the slim side of average, usually.

Not sure if that helps

 

[Goatboy]

I've used the Elite 4 well into the minuses, -12 on the deck with a standard Thermarest 3/4, and -9 in the hammock with a Snugpak underblanket. I sleep in 200g Woolpower top and bottoms and I'm on the slim side of average, usually.

Not sure if that helps

Aye but yer from Yorkshire and wouldn't waste good honest warmth! Hot gravel... Ohhhhh!

 

[Hibrion]

I remember reading somewhere that snugpack rating are averages based on two people sharing a tent and using a thermal barrier. Their definition of comfort is I think, 5 hours uninterrupted sleep. I can't remember where I read it though. I imagine most other manufacturers are similar. I think it's always best to have a bag that will work a little colder than you're likely to see. As you say, you can always open the zip.

My own experience of good quality bags is limited to snugpack, but I have been happy so far. I have a snugpack tactical 4 (comfort rating of -12, extreme -17) i bought on here an I've used it in a few degrees below zero in a hammock with a thermorest but no underquilt and I was very comfortable. I woke up with a cold nose and toes in the morning, but nothing worth worrying about.

 

[Clouston98]

Used my Nanok -5 at about -8 and it was still pretty warm, best sleeping bags in my opinion!

Hope this helps .

 

[Hypnagog]

Thanks for the replies so far.

I realise that it's a subjective experience and I like sleeping cold at home (with a fan on most nights), but one time I was out and it was much colder than I was prepared for (sitting up, tired and waiting for the sun to rise cold) and I guess since then I've gone overboard on the warmth.

I like the tagline on here that says something like, "Travel light, freeze at night" but really looking to cut the weight of my kit down, and I guess that a massively warm bag like the Antarctica RE falls into the "what if" category of kit, so am tentatively trying something a little lighter.

I've used the Elite 4 well into the minuses, -12 on the deck with a standard Thermarest 3/4, and -9 in the hammock with a Snugpak underblanket. I sleep in 200g Woolpower top and bottoms and I'm on the slim side of average, usually.

Not sure if that helps

That helps a lot, if the Elite 4 was fine, then the Elite 5 will be overkill, but not as much so as the Antarctica RE, so I'll be warm with the Elite 5.

The bags are tested by having (usually) a tank of water placed in them in a controlled environment and the cool rate measured. But us humans aren't standard things, so as well as all the aforementioned things some folk are just cold or hot sleepers.

Hope this helps a bit?

GB.

Yes, that helps thanks, and I didn't know that about the water tank. I guess it's a scientific way of doing things, but as you say doesn't relate to everyone.


I like the scientific way... I did try using a Thermolite Reactor Extreme the other night indoors, I placed Max/Min thermometer inside and one outside. The inside min temp was 25ºC whilst the outside room temp was 17ºC, so it did have some heat retaining properties, but I'm not so sure how it would fare inside a bag with freezing temps outside, obviously that isn't an absolute and would be related to outside temps.

Ratings are more of a guide line, I have 2 identical coleman bags bought at the same time and they perform differently but bothe are nowhere near there stated rating, for me anyway yet the wife finds them fine.

That's interesting, so no two bags are identical?

Used my Nanok -5 at about -8 and it was still pretty warm, best sleeping bags in my opinion!

Hope this helps .

Thanks

I guess what I need to do is give the Softie 9 Hawk and liner a go in the garden before I go to see what I think of it in colder temperatures.


Cheers all.

 

[Andy BB]

If you're ground-dwelling, look first for some sort of insulating layer underneath - the difference is astonishing. I'm thinking of a good insulating mat - exped do a range, both down and artificial (as do others). THe bottom of a sleeping bag is compressed by body weight, rendering the loft there virtually ineffective, and contact with the cold ground just leaches all the warmth out of a bag.

 

[Toddy]

I was just about to write that very thing too
What's under you and your bag is as important as the bag, and that's true whether on the ground or in a hammock.

I've got a Nanok bag and a buffalo liner, and when it's below freezing I still pack a hot water bottle. The bag is too blooming long though so I have to fold up all the loose at the foot end or my feet freeze.
Son1 swears by his Ajungilak and Son2 by a North Face one. Tbh, I think a lot of the ratings, while based on the same criteria, miss out because physically we're all different. I'm small and well padded, Son1 is 5'9" and heavily muscled, Son2 is a long, lanky six footer. I freeze in their sleeping bags and they don't like mine.
We 'all' like the down mat though

Sorry, not much help really; it's what suits you that matters.

cheers,
Toddy

 

[Goatboy]

...insulation from the ground, (the more a filling can be compressed the better a mat you'll need under you)...
GB.

@ Andy & Toddy; Beat ya both...

 

[PDA1]

Others below have already stated, but it is worth repetition, the insulating underlayer (pad/mat) is of critical importance. EN 13537 requires the test to be done with an approx 40 mm mat (r value about 3) to be used. It also assumes the sleeper is wearing afull base layer (long sleeve top, long johns) and a cap and neck warmer (balaclava?) plus knee length thick socks. If a mummy bag, head enclosed and opening cinched down leaving just nose and mouth exposed.

Then there is the sleepers condition: you need to be fully hydrated and fed ( cliff bar or Snickers plus a warm drink would be good just before bedding down). If your body is cold from sitting around in camp, increase core temperature before retiring with some form of activity. A slug of liquor would be a bad thing.

Think about this, the "extreme" rating under EN is the temperature at which a "standard" female probably (n.b. probably) won't die but may suffer frost bite.

Yes, personal differences do exist, but proper dress and practice (see above) can improve your performance by maybe 10 degrees

BTW, military sleep systems are not given EN ratings

EN ratings assume dry conditions, if it's humid, and in the UK it usually is, temperature raring suffers. Also applies to clothing, so the base layer and socks should be reserved for night use only, perspiration from daytime use destroys the insulative value.

 

[Hypnagog]

Thanks again everyone.

My sleeping mat is a full length self-inflating 2.5cm Vango "Ultralite" - it's not too bulky but looking at PDA1's specs above, it falls short of the 4cm testing. It's served me well so far, but I'm sure that I'll be tempted by a Thermorest or an Exped at some point.

It's good to know that there is no hard and fast rule. I guess we'll see what the weekend brings.

 

[Johnnyboy1971]

Just a quickie re sleeping mats, I have one of the Alpkit Wideboy mats and when inflated measures around 6cm thick.
This is all well and good when laid on your back as the weight is spread out but when you turn to your side the weight
distribution changes and as a narrower profile presses down, the thickness of the mat becomes less.
Mine starts off at 6cm, then when i lay on it on my back it is down to around 4cm. If i then turn on my side it goes down to 2cm and sometimes
i can feel the floor through the mat.

Its like the weight of a flat foot vs the stiletto heel.
Just food for thought.

Oh and i love my Nanok bags too especially for the bigger guys among us.

 

[PDA1]

@ hypnagog - For winter camping I'm a belt and braces type. I would add a cheap, 10-12 mm CCF pad to go under your self inflator. That way, if your self inflator punctures, you still have something.

 

[Andy BB]

Thanks again everyone.

My sleeping mat is a full length self-inflating 2.5cm Vango "Ultralite" - it's not too bulky but looking at PDA1's specs above, it falls short of the 4cm testing. It's served me well so far, but I'm sure that I'll be tempted by a Thermorest or an Exped at some point.

It's good to know that there is no hard and fast rule. I guess we'll see what the weekend brings.

Does the ultralite you're using have any form of insulation in it (foam/down)? Air alone doesn't do the trick - it just gets chilled by the ground and transmits it straight up into the bag! Which is why an air mattress is effectively useless on its own (and I speak from personal experience here) - you'll be comfier but just as cold....

 

[Dave-the-rave]

This is all a bit technical. Call me simple but warms warm and colds cold. Sleep in it and found out.

 

[Andy BB]

This is all a bit technical. Call me simple but warms warm and colds cold. Sleep in it and found out.

Since you asked - You're simple

 

[Dave-the-rave]

I'm good with that.

 

[rik_uk3]

2 litre pop bottle used as a hot water bottle makes an immense difference to any sleeping bag. Hot drink and a bit of food before sleep helps a lot.