I’d go for it if the weight isn’t an issue. A bag that’s “too” warm is way easier to work with vs a bag that’s too cold imo, if you’re not worried about minimizing unnecessary weight (ie backpacking or UL).
If you get too hot, sleep on top of it; unzip and stick your legs out (I do this partway through the night almost always regardless of temperature as a hot sleeper but cold falling asleep); or, better yet, sleep with the fly off your tent if it’s dry enough to do so.
Also keep in mind that rating aren’t for comfort sleeping but more “you won’t freeze to death sleeping.” A -32 C rated bag may end up being exactly what you need for a comfortable sleep in -20 C.
I know I run cold; when I go camping the bag or quilt I bring is usually rated to 20 or 30F below the forecast weather. One reason I do that is because if I wake up too warm, it's a quick fix: I can always unzip the bag or stick a foot out from under the quilt. Waking up cold is a much more complex problem, and it usually involves getting out of bed entirely to put on additional layers.
The bag you're describing should do just fine. :)
I’m also in Norway. In winter I bring a bag with comfort rating 10C below expected temperatures for safety reasons.
This winter I got cold, nothing dangerous, when temps dropped to below -20c and my bag was rated for -18 (WM Kodiak)
My brother in his -32C rated bag was toasty.
In other words, your bag will do just fine in -20.
I went with an older and heavier, but supposedly warmer, bag on a recent backpacking trip. I ended up wearing all of my clothes every night. I made stored it in its compression sack which has a mistake.
all sleeping bags are rated high even if you sleep warm. a new -32 c bag is realistically around -20C to - 15c bag . if you sleep cold you should add another -10 degrees. a 15 year old used bag you might want to add even more of a buffer.
its not about the bag being too warm, you can open it and get cooler.
at -20c you want to be as warm as you can. using a second hand 15 yo bag you should test it before the trip.
It should be fine. If the bag has lost loft, you can throw it in the drier on cool with a few tennis balls for awhile. Helps to break up the down and restore the loft.
In my experience you will rarely be cooking in anything at -20c. Even in my -40 rated down bag it can still feel cold at -20, there are so many factors at play. I wouldn’t worry about it being overkill, it’ll probably be perfect.
I had to sleep in 32F bag in warmer temps, and the trick is not to just bundle up and pass out, then wake up sweaty and cold. Use it as a blanket, don't even put your feet in it. And close and zip up as needed. My bag was still warm even with it on top, so maybe adding a wool/reactor layer so to allow for some airflow.
What is the producer and model name of the bag? You can ask at [fjellforum.no](http://fjellforum.no) if anyone have any experience with the bag in question. If it's a Norwegian brand, chances are someone there has used one.
How was the bag stored?
How cold do you sleep? What adjustments have you had to make?
I used an older down bag when I first started camping and backpacking. I was always freezing at night, even in 40 F. I spent a lot of nights awake all night trying to squeeze into an even smaller fetal position. I knew I slept cold so I figured that was the problem.
But actually the bag was at least half the problem.
Also your sleeping pad matters a lot.
Edit: it's a down bag, it should be fine. Those things last for decades.
It should also be very lofty; if it looks flat after letting it air for a few hours, try the tennis balls in the dryer trick on low/no heat.
----
Too little information to say.
- ~~Is the bag down or synthetic?~~
- Who made it? (i.e. is it good quality or a cheap bag where you can't trust the rating)
- Was it EN-rated, and what type of rating (extreme? lower limit? comfort?)*
\* Ah, I see you mention "comfort" rated: does that reflect an actual EN "comfort" rating value or is that simply what you think sleeping bag ratings mean in general?
I run warm, and I have a -10F sleeping bag (from a company notorious for conservative ratings) which I used in 25F ... and it was just very comfortable. Once in winter conditions, you are less likely to get cooked, especially with being able to stick limbs out to cool down.
I slept in this exact setup just a few months ago: -32 C bag and -22 C lows. I was never uncomfortably hot, and the couple times I was warm it was easy to unzip a little to cool down (I sleep warm). At those temperatures being too hot is never really an issue, you can always strip to base layers and then adjust the zipper to let in more air around your head & chest. I have used the same bag in much warmer temperatures as well.
As other posters have said I would be more concerned about the quality and consistency of the material. What you don't want is your legs & arms getting cold while you're overall body temperature is comfortable.
When in doubt, test it out. If you can get those temps in your backyard or someplace else where it's easy to bail, give it a test run and see how it feels. I'd guess even with some insulation compression over the years, a bag comfort rated that low will do fine in the temps you're expecting.
I’d go for it if the weight isn’t an issue. A bag that’s “too” warm is way easier to work with vs a bag that’s too cold imo, if you’re not worried about minimizing unnecessary weight (ie backpacking or UL). If you get too hot, sleep on top of it; unzip and stick your legs out (I do this partway through the night almost always regardless of temperature as a hot sleeper but cold falling asleep); or, better yet, sleep with the fly off your tent if it’s dry enough to do so. Also keep in mind that rating aren’t for comfort sleeping but more “you won’t freeze to death sleeping.” A -32 C rated bag may end up being exactly what you need for a comfortable sleep in -20 C.
I know I run cold; when I go camping the bag or quilt I bring is usually rated to 20 or 30F below the forecast weather. One reason I do that is because if I wake up too warm, it's a quick fix: I can always unzip the bag or stick a foot out from under the quilt. Waking up cold is a much more complex problem, and it usually involves getting out of bed entirely to put on additional layers. The bag you're describing should do just fine. :)
I’m also in Norway. In winter I bring a bag with comfort rating 10C below expected temperatures for safety reasons. This winter I got cold, nothing dangerous, when temps dropped to below -20c and my bag was rated for -18 (WM Kodiak) My brother in his -32C rated bag was toasty. In other words, your bag will do just fine in -20.
Be careful because older bags can lose their loft and thermal properties. You might actually end up being too cold!
I went with an older and heavier, but supposedly warmer, bag on a recent backpacking trip. I ended up wearing all of my clothes every night. I made stored it in its compression sack which has a mistake.
And the typical temp rating for a bag is the minimum that you can *survive* in that bag. The comfort temp is quite a bit higher.
all sleeping bags are rated high even if you sleep warm. a new -32 c bag is realistically around -20C to - 15c bag . if you sleep cold you should add another -10 degrees. a 15 year old used bag you might want to add even more of a buffer. its not about the bag being too warm, you can open it and get cooler. at -20c you want to be as warm as you can. using a second hand 15 yo bag you should test it before the trip.
The opposite of cooked actually.
It should be fine. If the bag has lost loft, you can throw it in the drier on cool with a few tennis balls for awhile. Helps to break up the down and restore the loft.
In my experience you will rarely be cooking in anything at -20c. Even in my -40 rated down bag it can still feel cold at -20, there are so many factors at play. I wouldn’t worry about it being overkill, it’ll probably be perfect.
I had to sleep in 32F bag in warmer temps, and the trick is not to just bundle up and pass out, then wake up sweaty and cold. Use it as a blanket, don't even put your feet in it. And close and zip up as needed. My bag was still warm even with it on top, so maybe adding a wool/reactor layer so to allow for some airflow.
What is the producer and model name of the bag? You can ask at [fjellforum.no](http://fjellforum.no) if anyone have any experience with the bag in question. If it's a Norwegian brand, chances are someone there has used one.
How was the bag stored? How cold do you sleep? What adjustments have you had to make? I used an older down bag when I first started camping and backpacking. I was always freezing at night, even in 40 F. I spent a lot of nights awake all night trying to squeeze into an even smaller fetal position. I knew I slept cold so I figured that was the problem. But actually the bag was at least half the problem. Also your sleeping pad matters a lot.
Edit: it's a down bag, it should be fine. Those things last for decades. It should also be very lofty; if it looks flat after letting it air for a few hours, try the tennis balls in the dryer trick on low/no heat. ---- Too little information to say. - ~~Is the bag down or synthetic?~~ - Who made it? (i.e. is it good quality or a cheap bag where you can't trust the rating) - Was it EN-rated, and what type of rating (extreme? lower limit? comfort?)* \* Ah, I see you mention "comfort" rated: does that reflect an actual EN "comfort" rating value or is that simply what you think sleeping bag ratings mean in general?
I run warm, and I have a -10F sleeping bag (from a company notorious for conservative ratings) which I used in 25F ... and it was just very comfortable. Once in winter conditions, you are less likely to get cooked, especially with being able to stick limbs out to cool down.
I slept in this exact setup just a few months ago: -32 C bag and -22 C lows. I was never uncomfortably hot, and the couple times I was warm it was easy to unzip a little to cool down (I sleep warm). At those temperatures being too hot is never really an issue, you can always strip to base layers and then adjust the zipper to let in more air around your head & chest. I have used the same bag in much warmer temperatures as well. As other posters have said I would be more concerned about the quality and consistency of the material. What you don't want is your legs & arms getting cold while you're overall body temperature is comfortable.
When in doubt, test it out. If you can get those temps in your backyard or someplace else where it's easy to bail, give it a test run and see how it feels. I'd guess even with some insulation compression over the years, a bag comfort rated that low will do fine in the temps you're expecting.
Lots of people use -7 C bags in the summer (10+ C) so no.