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MattSin97
01-03-2019, 16:21
Hey everyone!

So I was finally able to test out my Kelty Comsic 20 and it did not live up to expectations. I went out in around 40 degrees with three layers (REI midweight base, Patagonia R1, and marmot precept) and was uncomfortably cold to say the least. I decided to ditch the Kelty and move on to something warmer. I will be starting my AT hike mid march, and I hear it can still be plenty cold during that time.

Does anyone have any recommendations on a sleeping bag and/or quilt? I was looking for something mid-tier, 20 degree bags/quilt that will be warmer than the Kelty. I do sleep very cold. My price range is around 250-300 dollars. Any recommendations is greatly appreciated!

Cheyou
01-03-2019, 16:22
What pad did you use ??

jungleland1972
01-03-2019, 16:25
I just used a Hyke & Byke 800 fill 0 degree bag overnight in Maryland (on the AT) and was pretty comfortable in the low 30's (I sleep really cold as well): https://www.amazon.com/Hyke-Byke-Goose-Sleeping-Backpacking/dp/B07BSX9SHW

I think $ for warmth it's a good bag, light and packs small.

Gambit McCrae
01-03-2019, 16:27
The pad is equally important as the bag. If I have to wear more than my underwear to sleep then I deem my pad and sleeping bag to not be sufficient enough for the outing I have chosen to go on.

I have always seen buying a sleeping bag as a long term investment. IF you get something like a montbell, WM or EE it is going to pricey, but you will be warm to the rating of the bag and it will last a lifetime. As far as pads go, I would suggest Exped. They have a broad range of temp ratings and excellent customer service.

scope
01-03-2019, 16:36
Do you really think the 20 rating on the Kelty is so overblown so as to be useless at 40? Read up some.

MattSin97
01-03-2019, 16:52
The pad is equally important as the bag. If I have to wear more than my underwear to sleep then I deem my pad and sleeping bag to not be sufficient enough for the outing I have chosen to go on.

I have always seen buying a sleeping bag as a long term investment. IF you get something like a montbell, WM or EE it is going to pricey, but you will be warm to the rating of the bag and it will last a lifetime. As far as pads go, I would suggest Exped. They have a broad range of temp ratings and excellent customer service.

My sleeping pad R-value is rated at 4.4. Didn't really feel cold from under.

MattSin97
01-03-2019, 16:54
What pad did you use ??


I used a Klymit Insulated Static V LITE rated with an R-value of 4.4.

https://www.amazon.com/Klymit-Insulated-Static-4-Season-Sleeping/dp/B00UW7LEOW/ref=sr_1_1_sspa?s=sporting-goods&ie=UTF8&qid=1546548863&sr=1-1-spons&keywords=Klymit+Insulated+Static+V+LITE&psc=1

MattSin97
01-03-2019, 16:55
Read up on what exactly?

MattSin97
01-03-2019, 17:00
Do you really think the 20 rating on the Kelty is so overblown so as to be useless at 40? Read up some.

I wouldn't say useless, I would say uncomfortable. Perhaps others would feel fine in it, I didn't. I'm a cold sleeper and it didn't provide the warmth needed for me to get a good nights rest. Just looking for some alternatives before I set out.

The Old Chief
01-03-2019, 17:10
I also sleep cold and have been using for several years a 0 degree Montbell bag for cold weather (30 degrees and below for me). On several trips on the Ga. AT it kept me toasty in early March. I also use an EE 20 degree quilt from about 30 degrees to 50 degrees and it keeps me warm for those temps. I use an EE 40 degree quilt for above 50. I like to sleep warm. These should all be in your price range and available by your start date. All my stuff is down but Montbell and EE also make their bags and quilts with synthetic fills bringing down the price of each considerably.

scope
01-03-2019, 17:10
Read up on what exactly?

You were cold from within, your pad and bag were sufficient to reduce heat transfer, just didn't have much to work with. Ditch the layers and warm yourself up some - the bag needs your warmth to fully loft. The Precip likely held in some normal perspiration, too. (not sweat since you were cold)

Not saying the Cosmic is the bees knees for insulation - it looks dubious at 30 for me despite its good reviews - but its clear that it should've been sufficient at 40. Made this same mistake before - I'm layered up to deal with the cold from sitting around camp and eventually its too cold for the layers to deal with so I climb in a bag, layers and all, expecting it to warm me. You actually have to warm it for it to work like you expect it to.

MattSin97
01-03-2019, 17:16
You were cold from within, your pad and bag were sufficient to reduce heat transfer, just didn't have much to work with. Ditch the layers and warm yourself up some - the bag needs your warmth to fully loft. The Precip likely held in some normal perspiration, too. (not sweat since you were cold)

Not saying the Cosmic is the bees knees for insulation - it looks dubious at 30 for me despite its good reviews - but its clear that it should've been sufficient at 40. Made this same mistake before - I'm layered up to deal with the cold from sitting around camp and eventually its too cold for the layers to deal with so I climb in a bag, layers and all, expecting it to warm me. You actually have to warm it for it to work like you expect it to.

The thing is, I didn't start with all those layers. I added a layer about every hour because I was still really cold. I'm not sure what went wrong.

scope
01-03-2019, 17:18
FWIW, the more you spend, the more you get closer to something that works more efficiently at trapping your body heat. You're gonna give off some no matter what you're wearing, its just that I think the minimal down in the Kelty (enough down to justify its rating) needed more from you. The more expensive bags seem to need less from you to work well, whether that's a function of more down, better down, or much more conservative rating, I don't know.

tdoczi
01-03-2019, 17:19
Do you really think the 20 rating on the Kelty is so overblown so as to be useless at 40? Read up some.
i have the 40 degree version of the exact same bag and have used it probably down to 35. cant say i was toasty warm but it was workable. i too have trouble thinking the 20 degree bag doesnt work at 40 degrees.

scope
01-03-2019, 17:27
The thing is, I didn't start with all those layers. I added a layer about every hour because I was still really cold. I'm not sure what went wrong.

Did you make it overnight, or bail? Once cold, its really hard to shake it. Again, the bag doesn't warm you, its the other way around. When your body gets cold, it starts getting defensive and shutting down blood flow in areas. It gets conservative with your body heat, whereas you need your body to get liberal with it, to some degree. With a fully lofted bag, you can be insulated so that heat production and loss reach an equilibrium = comfort.

I'm also a cold sleeper and I always maintain a 10-degree rule for the insulation I bring, meaning I bring my 20 degree stuff for being in the 30s, maybe high 20s.

MattSin97
01-03-2019, 17:29
FWIW, the more you spend, the more you get closer to something that works more efficiently at trapping your body heat. You're gonna give off some no matter what you're wearing, its just that I think the minimal down in the Kelty (enough down to justify its rating) needed more from you. The more expensive bags seem to need less from you to work well, whether that's a function of more down, better down, or much more conservative rating, I don't know.

Thanks for the insight, I think I'm just already worried about Being warm enough, especially since I already sleep cold, that I would feel more comfortable with a bag/ quilt that needs less from me to become warm.

MattSin97
01-03-2019, 17:32
I made it through, but I didn't sleep much at all. I'm notoriously unmotivated and anxious without a good nights sleep. I'm trying to gauge how the weather will be on the AT, but I see it's variable, so I want to err on the side of being too warm rather than too cold.

ant
01-03-2019, 17:37
I like, when I'm using a sleeping bag vs a quilt, the Marmot Sawtooth. It's a 15 degree with draft tubes. Very comfortable and true to it's rating. It's affordable and well reviewed.

I don't use mine anymore due to using quilts now.

Decibel
01-03-2019, 17:38
Look into Western Mountaineering sleeping bags. Pricey but you will not regret it.

MattSin97
01-03-2019, 17:42
I like, when I'm using a sleeping bag vs a quilt, the Marmot Sawtooth. It's a 15 degree with draft tubes. Very comfortable and true to it's rating. It's affordable and well reviewed.

I don't use mine anymore due to using quilts now.

Thanks, any recommendations on quilts?

Venchka
01-03-2019, 18:45
Look into Western Mountaineering sleeping bags. Pricey but you will not regret it.
Like all bags, pay attention to the inside dimensions of WM bags.
If you are comfortable in the Kelty bag all zipped up and the hood drawn up around your head then a similar internal sized WM bag should work.
Also look at the top loft of various bags. In my experience, a bag with 3 of down over your body plus the appropriate sleeping system accessories will be fine easily into the teens and single digits for a fairly warm sleeper like me.
Until you can figure out what you need to sleep well in the teens or below you really dont know what bag is going to work for you. It wont be a quilt in March.
Good luck!
Wayne

Time Zone
01-03-2019, 22:02
I sleep cold too and haven't figured out how to stay toasty warm into the 40s either. I'm merely "OK" down to 40F in a 20F bag, but far from toasty (more like neutral to cool-ish), and being toasty is how I get the most sound sleep. I'd like to gradually extend my comfort range down to 30F at least.

I'm looking into more pad insulation (beyond RR solar) and perhaps most importantly warmer PJs (like fleece; I had been wearing Duofolds, thinner and tighter). My pad strategy is very up in the air (so to speak) since I hate crinkly noisy pads and don't trust inflatables in winter (when failure has the greatest cost) anyway. First step will be to switch to warmer PJs. Maybe add a 2nd, thin, CCF to the RR Solar.

At some point, even more down (like a 0F bag) gets too bulky unless you pony up for the high fill power stuff. I'd prefer not to have to get high fill power, since I live in the very humid southeast, but I don't know how I'd get a warm enough yet packable bag otherwise.

scrabbler
01-03-2019, 23:04
I never sleep well/warm the first night or two. Anxiety or whatever plays a part. Give it a few nights and hike harder each day. You'll sleep.

OwenM
01-04-2019, 04:38
For starters, the fact that you even have midweight baselayers, much less R1 anything, along at those temps does point to indeed running very cold(so where was your insulated jacket?).

Google says your bag has a lower limit rating of 19, but a comfort rating of 30, and you already know it isn't going to work for you, even at that. You're obviously going to need something rated well below actual temps. How much so you'll have to discover yourself, but it sounds like you might be in the same boat with The Old Chief.
The good news is that you can get a genuine 0 degree bag with 800-850 fill for the same weight as that Kelty. The bad news is that it's likely going to cost $500+ unless you catch a good sale. At least anything from a brand I'd feel comfortable buying from. Of all your gear, the sleep system is the last thing to skimp on, though.

4eyedbuzzard
01-04-2019, 07:21
Traditionally, a TRUE 20F bag was a good compromise for a thru-hike using just one bag - back when the traditional start date was April 15, not March 15. Allowing 2 weeks +/- to Fontana Dam, there's a big difference in weather between April 1 and May 1, especially at higher elevations in GSMNP. Average lows are probably around 30F around Apr 1 in the higher mountains, but the deviations from average can be +/- 20F. Add in cold, tired, possibly wet, etc., and a 20F bag is really marginal for a March start.

scope
01-04-2019, 07:52
I use quilts, but hang a hammock instead of using a tent. Just remember its the same issue with quilts, but most quilt makers are cottage, not commercial, and most are of WM or FF quality but of lower price. Some recommendations:

HammockGear.com (Econ Burrow is just of slightly heavier material, but still very light considering, probably best value)
LocoLibreGear.com
EnlightenedEquipment.com
UGQoutdoor.com
Arrowhead-Equipment.com (makes good syn quilts)

cmoulder
01-04-2019, 10:09
I used a Klymit Insulated Static V LITE rated with an R-value of 4.4.

https://www.amazon.com/Klymit-Insulated-Static-4-Season-Sleeping/dp/B00UW7LEOW/ref=sr_1_1_sspa?s=sporting-goods&ie=UTF8&qid=1546548863&sr=1-1-spons&keywords=Klymit+Insulated+Static+V+LITE&psc=1

Ok, but even so I would try a different air mat such as a TR Xtherm. OR add a 1/2" closed-cell foam mat to your current Klymit air mat.

ant
01-04-2019, 11:56
Thanks, any recommendations on quilts?

Honestly I would not recommend a quilt for you right now. They require a little experience to use, some getting used to and if you move a lot, don't wear the right headwear, etc. it's easy to get cold/lose heat.

There are a plethora of great makers. Feel free to try em out, but familiarize yourself with their use. If you did go that route, I'd suggest a 10 degree and if you end up finding yourself too hot, sell it and get a good 20 degree. Good gear holds it's value very well.

soumodeler
01-04-2019, 12:10
I had the same issue with a Cosmic Down 20. It was simply not as warm as it should have been. I switched to a REI Igneo 19, which has the same comfort rating, and was way warmer. Same pad, same tent, etc.

One thing I did not realize is the Kelty is not 100% down, it is 16% polyester fill according to REI. I had a lot of problems getting the fill on the Kelty to spread out evenly. That poly fill may have something to do with it and the temp issues I experienced.

I now have several Western Mountaineering bags, and the difference is amazing. Quality gear really shows - my WM Alpinlite (20*) has 21 ounces of fill compared to the REI Igneo (19*) at 16.7 ounces. From everything I have heard, WM bags can last decades with proper care, so I consider these a long term investment.

OwenM
01-04-2019, 12:51
On the quilt subject: If you do try a quilt for low temps, a good pad attachment system, and enough width to completely encircle you aid in eliminating drafts. Some people are of the opinion that a quilt gives up warmth relative to a bag of equal loft, etc. That may be true due to inadequate sizing and setup, or just inferior design, but it doesn't have to be.
There's going to be some fiddle factor with a quilt, and you'll probably want a separate down hood to go with it. Quilts attached to the pad really shine for active sleepers who twist around a lot plus end up breathing into their bag since those same "compromises" become advantages. That's one of the main reasons I decided to try quilts, and they worked out great for me. Now that I've become more of a back sleeper, it doesn't make that much difference as far as comfort, but still saves a little weight.

ant
01-04-2019, 12:54
On the quilt subject: If you do try a quilt for low temps, a good pad attachment system, and enough width to completely encircle you aid in eliminating drafts. Some people are of the opinion that a quilt gives up warmth relative to a bag of equal loft, etc. That may be true due to inadequate sizing and setup, or just inferior design, but it doesn't have to be.
There's going to be some fiddle factor with a quilt, and you'll probably want a separate down hood to go with it. Quilts attached to the pad really shine for active sleepers who twist around a lot plus end up breathing into their bag since those same "compromises" become advantages. That's one of the main reasons I decided to try quilts, and they worked out great for me. Now that I've become more of a back sleeper, it doesn't make that much difference as far as comfort, but still saves a little weight.

^____ All of this

MattSin97
01-04-2019, 13:53
For starters, the fact that you even have midweight baselayers, much less R1 anything, along at those temps does point to indeed running very cold(so where was your insulated jacket?).

Google says your bag has a lower limit rating of 19, but a comfort rating of 30, and you already know it isn't going to work for you, even at that. You're obviously going to need something rated well below actual temps. How much so you'll have to discover yourself, but it sounds like you might be in the same boat with The Old Chief.
The good news is that you can get a genuine 0 degree bag with 800-850 fill for the same weight as that Kelty. The bad news is that it's likely going to cost $500+ unless you catch a good sale. At least anything from a brand I'd feel comfortable buying from. Of all your gear, the sleep system is the last thing to skimp on, though.

I found the REI MAGMA 10 on sale which is rated as a 10 degree bag. It's 850 fill and just under 2 pounds at around $250. It seems like a good deal and the reviews seems pretty positive so I have that in my sights right now. I have also been looking at the quilts, but like others have said, there seems to be a learning curve to using them with some aspects, and since it's close to my start date I would need to get a ready to ship one instead of a custom. I'm still on the fence, but I'm a little weary of trying them out, especially because I'm already having problems staying warm.

MattSin97
01-04-2019, 13:54
WM bags look awesome, but they are a little out of my price range at the moment. I'm sure halfway thru my hike I will have wished I spent the money, I hear nothing but good things about WM.

HooKooDooKu
01-04-2019, 14:50
For times where you might be just a little cold, you might want to look into adding layers on TOP of your sleeping bag.

An early spring weekend trip last year turned unexpectedly cold. I expected temps in the mid 40's and took my Mountain Hardware 32 bag.
It got uncomfortably cold in the middle of the night as the actual temps dipped into the mid 30's.

I carry a puffy jacket for use in camp to stay warm, but would never consider wearing it while sleeping (my body would just compress the down leaving almost nothing for insulation).

I draped the puffy OVER my sleeping bag, and it added just the right amount of warmth that I was able to sleep fine the rest of the night.

Cheyou
01-04-2019, 14:59
Try 2 pads . I get the money thing , if I slept cold I would go bag not quilt. But once cry once. Western mountain, feathered friends. If you don’t sleep well , you are in trouble.

OwenM
01-04-2019, 15:24
I found the REI MAGMA 10 on sale which is rated as a 10 degree bag. It's 850 fill and just under 2 pounds at around $250. It seems like a good deal and the reviews seems pretty positive so I have that in my sights right now.
I looked at it; they just show the long 6'6" version available. Reviews don't look that positive to me for a cold sleeper. But..how tall are you? If you're under 6' and slim, look at the women's long version's specs and reviews, as that's a better bag for a cold sleeper(if it'll fit you).
6" shorter bag with 695g/24.5oz of fill vs 540g/19oz.
Lower limit 3F vs 10F
Comfort rating 17F vs 22F
It does have 2" less girth at the shoulders(do keep in mind that the men's version is slim, too) and weigh 6oz more, but that's practically all down.
And check your private messages. Gonna send you a coupon code in case you buy from REI...

Time Zone
01-04-2019, 17:04
I found the REI MAGMA 10 on sale which is rated as a 10 degree bag. It's 850 fill and just under 2 pounds at around $250. It seems like a good deal and the reviews seems pretty positive so I have that in my sights right now. I have also been looking at the quilts, but like others have said, there seems to be a learning curve to using them with some aspects, and since it's close to my start date I would need to get a ready to ship one instead of a custom. I'm still on the fence, but I'm a little weary of trying them out, especially because I'm already having problems staying warm.

Outdoor Gear Lab reviewed that bag and it's worth checking it out. IIRC they viewed the temperature rating as quite optimistic.

One of the reasons for this, I believe, is that the bag is designed so that it's very lightly insulated on the backside. The down is almost all on the topside, so it's designed for back sleepers. The bag itself is pretty narrow, and as such, it's likely to roll with you if you're a side sleeper, exposing that under-insulated backside. You mentioned quilts. If you're a back sleeper, this could be a great alternative to a quilt, since you won't have to worry as much about drafts - the bag is already wrapped around you. No sleeping on straps, cords, or buckles either.

MattSin97
01-04-2019, 19:36
Outdoor Gear Lab reviewed that bag and it's worth checking it out. IIRC they viewed the temperature rating as quite optimistic.

One of the reasons for this, I believe, is that the bag is designed so that it's very lightly insulated on the backside. The down is almost all on the topside, so it's designed for back sleepers. The bag itself is pretty narrow, and as such, it's likely to roll with you if you're a side sleeper, exposing that under-insulated backside. You mentioned quilts. If you're a back sleeper, this could be a great alternative to a quilt, since you won't have to worry as much about drafts - the bag is already wrapped around you. No sleeping on straps, cords, or buckles either.

I saw the review on out gear lab as well, but I tried not to be too let down by its warmth rating there considering they were reviewing it under winter bags, and I will will be using it as a 3- season with occcasional dips into winter temps. The bag is a narrow bag, which can be considered constricting, but I consider a greater warmth factor.

MattSin97
01-04-2019, 20:08
For times where you might be just a little cold, you might want to look into adding layers on TOP of your sleeping bag.

An early spring weekend trip last year turned unexpectedly cold. I expected temps in the mid 40's and took my Mountain Hardware 32 bag.
It got uncomfortably cold in the middle of the night as the actual temps dipped into the mid 30's.

I carry a puffy jacket for use in camp to stay warm, but would never consider wearing it while sleeping (my body would just compress the down leaving almost nothing for insulation).

I draped the puffy OVER my sleeping bag, and it added just the right amount of warmth that I was able to sleep fine the rest of the night.

Very interesting, I've never considered draping my puffy over the bag, but it makes sense. I will definitely be trying it out!

Slo-go'en
01-04-2019, 21:21
I think you need to bite the bullet and get a 0 bag. It's good to have serious overkill early on. When you've been hiking in 35 degree rain all day, you want a really warm bag.

Save the Cosmic for when it warms up in Virginia. Depending on when you get to Maine, you might want the 0 bag back.

MattSin97
01-04-2019, 21:34
I think you need to bite the bullet and get a 0 bag. It's good to have serious overkill early on. When you've been hiking in 35 degree rain all day, you want a really warm bag.

Save the Cosmic for when it warms up in Virginia. Depending on when you get to Maine, you might want the 0 bag back.

True. Is there a reason why the majority of thru hikers (based on the thru hiker survey @thetrek.co) opt for the 20 degree? Or is it a better safe than sorry because I tend to sleep cold to get a 0 bag?

Venchka
01-04-2019, 23:30
Very interesting, I've never considered draping my puffy over the bag, but it makes sense. I will definitely be trying it out!
I drape my down garments, vest or jacket, over my torso inside the bag. They stay in place better. If the vest or jacket falls off of me its easier to find in the dark inside the bag.
At altitude, March can be Winter. April too on occasion.
On economics: You bought a Kelty bag. Youre contemplating buying an REI bag. Youre probably going to spend half the price of quality bag and still wont know if the bag will keep you warm. High quality down bags are a one and done purchase. The most economical solution to sleeping soundly over a wide range of conditions.
Wayne

Slo-go'en
01-05-2019, 02:18
/
True. Is there a reason why the majority of thru hikers (based on the thru hiker survey @thetrek.co) opt for the 20 degree? Or is it a better safe than sorry because I tend to sleep cold to get a 0 bag?

Zero might be a bit too much overkill. A 10 degree bag would be a good compromise which saves a little money, weight and bulk. Or maybe you just need a silk liner and a better choice of sleeping clothes. Delaying the hike until April is a big help.

It's all about trade offs. Most people only want to buy one bag. For a late March/early April start a 20 degree bag is a reasonable choice. Most of the time it will stay above freezing and for the few nights that it isn't, you just suffer through them.

Adding the silk liner and sleeping in a tent helps add 10-15 degrees to your bag rating. Socks, a light base layer top and bottom and a hat are standard sleepwear. Another thing to consider is you do get acclimated to the cold. After living outdoors in the cold for a week or so, the body starts to adapt. Spending a lot of time outside in the cold before you start the hike helps too.

Starting in early to mid March, the chances of your seeing temps in the 20's or lower are much greater so having a warmer bag then 20 is desirable. Unless you really like to suffer. Or spend the cold snaps in a motel in town.

Venchka
01-05-2019, 10:46
Obviously. Not all sleeping bags are created equal.
Your internal thermostat needs a few days to switch from central heating to Mother Natures air conditioning.
Dumb luck got me a decent bag in the early 70s. The REI Summerlite. Slim cut. Full hood. 1.5 ounce shell. 20 ounces of goose down. 3 top loft and 2 bottom loft. No temperature rating back then. Proven warm on several frigid nights in the Rockies. $68 as I recall. My oldest granddaughter has it now.
I replaced that bag with a 20 degree WM Alpinlite. I tried to like the WM Ultralite, but I had gotten tired of snug sleeping bags. The coldest, verified morning low that I have seen in the Alpinlite is 15 F on an Xtherm Large and my standard late summer in Rockies base layer clothing from head to toe. The Alpinlite is sold in Europe with a Lower Limit rating of 16 F. I agree with that rating and I could probably be comfortable below 15 F in 250 weight Merino wool underwear.
I would still be using the REI bag if I hadnt felt like treating myself to a present.
If you really are a cold sleeper, I strongly recommend either the 10 F WM Versalite or the 5 F WM Antelope MF.
Buy quality once.
Wayne

Venchka
01-05-2019, 10:50
PS:
On the other side of the temperature scale, I havent died in any of my sleeping bags in temperatures from 40 degrees to mid-50 degrees.
Wayne

Teacher & Snacktime
01-05-2019, 14:16
Nothing went wrong. If you're a cold sleeper then the Kelty Cosmic 20* Down is good to about 45*. I LOVE my Kelty, but it's only a late spring/early fall bag. The last time I used it in Connecticut in a chilly May (47*) I was uncomfortable all night. Yes, I had an appropriate pad, clothing, etc. What I did discover is that a cheap fleece throw, one of those 1 lb bags, thrown over the top does wonders. But hey, if you're going to carry that extra bulk and weight, you might as well get a heavier and warmer bag. The 0* will take you to 20-30 pretty well if you're attracted to the Kelty price.

Time Zone
01-05-2019, 14:27
What I did discover is that a cheap fleece throw, one of those 1 lb bags, thrown over the top does wonders. But hey, if you're going to carry that extra bulk and weight, you might as well get a heavier and warmer bag.
I have found that too - a 1 lb Costco Down throw thrown over, made a huge difference for me, warmth wise. It has about 7 oz of down; the rest is shell. But I think it's warmer than if you had those 7 ounces of down in your bag. I suspect the shell provides a bit of insulation too - like just a UL windshirt (two, really). You can double it over for even more warmth ... but it has a tendency to slide off, so you need quite a narrow tent to have a hope of keeping it on.

The Old Chief
01-05-2019, 17:01
I see that REI sells the Kelty Cosmic 0 degree bag for $229.95 with free shipping. If you like everything about your Kelty Cosmic 20 except for the warmth factor maybe the 0 degree version would be okay. If you try it out one night and it doesn't do the job send it back. On my first AT hike in 2001 I used a 20 degree Campmor down bag. It had 650 down fill and cost about $115.00. I started on March 5th and the first night out of the NOC it got down to 8 degrees and I got cold. But so did everybody else in the shelter. The next night was just a few degrees warmer but I slept in my tent and stayed fairly warm.

MattSin97
01-05-2019, 19:53
I see that REI sells the Kelty Cosmic 0 degree bag for $229.95 with free shipping. If you like everything about your Kelty Cosmic 20 except for the warmth factor maybe the 0 degree version would be okay. If you try it out one night and it doesn't do the job send it back. On my first AT hike in 2001 I used a 20 degree Campmor down bag. It had 650 down fill and cost about $115.00. I started on March 5th and the first night out of the NOC it got down to 8 degrees and I got cold. But so did everybody else in the shelter. The next night was just a few degrees warmer but I slept in my tent and stayed fairly warm.

I decided to try out the REI MAGMA 10. I'm going to try it out in some cold weather in the mountains by my house. If it doesn't do the job I may return it and continue my search. I just want to say a big thank you for everyone's and their input. I will be keeping all the information in mind while adjusting my sleep system. Has anyone had any success with bag liners in adding any warmth? Not sure if I'm going that route but I've been starting to read up about them and was wondering if anyone had any thoughts.

MattSin97
01-05-2019, 19:56
Nothing went wrong. If you're a cold sleeper then the Kelty Cosmic 20* Down is good to about 45*. I LOVE my Kelty, but it's only a late spring/early fall bag. The last time I used it in Connecticut in a chilly May (47*) I was uncomfortable all night. Yes, I had an appropriate pad, clothing, etc. What I did discover is that a cheap fleece throw, one of those 1 lb bags, thrown over the top does wonders. But hey, if you're going to carry that extra bulk and weight, you might as well get a heavier and warmer bag. The 0* will take you to 20-30 pretty well if you're attracted to the Kelty price.

Happy to know I'm not alone! I'm really not used to cold weather right now, and I'm sure that is a factor as well. I haven't looked into a throw, but I will keep it in mind, thanks.

Venchka
01-05-2019, 20:58
You live in California.
Youre testing gear and getting ready in California.
You want to go east to go hiking?
You do know that theres a relatively well known trail that runs the length of California?
I just dont get it.
Good luck!
Wayne

wordstew
01-07-2019, 15:26
How about adding the trifecta bivy or the grabber blanket into your sleep system

https://www.amazon.com/2GoSystems-Trifecta-Standard-Thermally-Reflective/dp/B01971DQRQ

https://www.amazon.com/Grabber-All-Weather-Blanket-Blue/dp/B001OPM25G/ref=sr_1_4?s=sporting-goods&ie=UTF8&qid=1546889175&sr=1-4&keywords=grabber+blanket

scope
01-07-2019, 16:28
Nothing went wrong. If you're a cold sleeper then the Kelty Cosmic 20* Down is good to about 45*. I LOVE my Kelty, but it's only a late spring/early fall bag. The last time I used it in Connecticut in a chilly May (47*) I was uncomfortable all night. Yes, I had an appropriate pad, clothing, etc. What I did discover is that a cheap fleece throw, one of those 1 lb bags, thrown over the top does wonders. But hey, if you're going to carry that extra bulk and weight, you might as well get a heavier and warmer bag. The 0* will take you to 20-30 pretty well if you're attracted to the Kelty price.

Maybe. Look, I've been cold in a zero bag before in the 20s, too. I just don't think what we're talking about here is ALL on the Kelty. Its simply not that bad. But, let's talk some numbers... WM uses 16oz of 850+ down in their 20 degree reg size bag. Safe to say they have less volume to fill as well given the nature of their bags. The Kelty uses 21oz of 600 fill down that is likely of low quality given the price. The fill potential per oz of down is 30% greater for WM. The Kelty has more down, but the Kelty likely has more volume to be filled - hard to say, but I'm going on what I know about WM bags vs commercial bags - the Kelty is described as "roomy" whereas WM are normally very fitted. So let's say that's a wash, and that if the WM is a true 20 degree bag (given its cost it better be), then discoun the Kelty by 30% which makes it more like a 29 degree bag. And given what I know to be a standard 10 degree cushion for comfort (my experience as a cold sleeper), you ought to be able to use the Kelty Cosmic 20 at 40 degrees without issue. Most certainly at 45.

Now, maybe that's borderline for some depending on how you sleep, cold or real cold. I'm going to say that if you don't do something else to help your bags work like they're supposed to, you're always going to run into issues with being cold if you're not over-insulated. You're always going to have not only more bag than you need, but a whole lot more. Unlike Geico, that has an adverse affect down the line if you backpack, or just in terms of how much you end up spending overall. You can certainly get the Kelty zero bag, but where are you then in terms of weight and bulk and the extra amount paid? If you're strictly a camper, of course it doesn't matter much. Just saying that "more" isn't always better if you look at everything you're doing as a whole. It may work in terms of keeping you warm, but again, you're better off figuring out HOW to stay warm in a product that should be able to keep you warm at a certain temp, like the Kelty Cosmic 20 at 40+.

Time Zone
01-07-2019, 22:02
It's possible the Kelty bag would perform better with fleece PJs and a self-inflating pad (which is the kind used in setting EN ratings). Fleece PJs have 2.6x the insulating value (in terms of CLO) vs. thermal underwear, according to research by KSU's McCulloch, et al.

IDK about the klymit insulated static V pad (light or regular) but I've always been suspicious of that R-value rating on a pad with that design. Seems easy for cold air to get under you and your bag, with those deep welds. FWIW McCullough's research seemed to show declining marginal value of pad thickness after the first inch. A 1" self inflator had about 85% of the insulating value, on average, of a 2.5" thick self-inflator. Nothing about pure air pads.

Klymit makes a 0F bag that has a whopping 1200g of 650 fp down. That's over 42 oz, and it's not oversized in dimensions at all. That thing lofts like crazy. However, I found the down clumps, or clings, to itself, leaving uninsulated voids in the baffles. No-heat dryer with tennis balls didn't solve the problem.

But in general, I think a low fill power bag can loft as much as a high end bag. You just gotta put in a lot more down to get there, and thus deal with higher weight (and maybe bulk too). Your reward is price.

Teacher & Snacktime
01-08-2019, 13:57
I just don't think what we're talking about here is ALL on the Kelty. Its simply not that bad.

Don't misunderstand, I LOVE my Kelty 20*. It's not bad at all, but for me it's inadequate for temps near 40, so I bring either a throw also or make sure I have enough fleece clothing to keep me warm.

4eyedbuzzard
01-08-2019, 18:30
Kelty calls it the Cosmic 20. But the 20 (actually 19) "rating" is for a man, curled up, and pretty much doing everything possible just to stay warm enough not to wake up from being cold. That's not necessarily really comfortable. But the EN comfort rating (the so-called "women's rating") is 30F. ALL EN ratings assume the use of not just an insulated pad, but also being inside a tent, and wearing a base layer and hat and socks. The test is done on a heated mannequin with temperatures sensors on it in a cold box (not in real world field conditions), so there is very little convective heat loss from any wind or breeze. Even a very slight breeze will affect how warm a sleeping bag will keep you. The test also assumes a kind of average nighttime base metabolic rate. Some people just don't produce as much body heat throughout the night. Then add that as a bag ages and is used, it loses loft and insulation value due to being damp (almost a given on the AT), dirty, clumping, etc. Then add in if you're hungry, dehydrated, tired, damp/wet, etc. , and that 20F bag, which is really at best a 30F bag, will have many people wishing for a warmer bag even at 40F.

Venchka
01-08-2019, 23:48
... and not giving your body sufficient nights to adjust to your surroundings.
To the person who defined Western Mountaineering sleeping bags as tight fitting: Look carefully at the inner dimensions on their web site. I count 4 bags with a 59 shoulder girth. A fraction of the total offerings.
Wayne

4eyedbuzzard
01-09-2019, 07:22
... and not giving your body sufficient nights to adjust to your surroundings.
To the person who defined Western Mountaineering sleeping bags as tight fitting: Look carefully at the inner dimensions on their web site. I count 4 bags with a 59” shoulder girth. A fraction of the total offerings.
WayneOne of the reasons, beyond just overall quality and warmth, that I like them. Enough room so my arms don't get trapped trying to unzip them from the inside. Lots of bags with 62" and more of girth.

Zalman
01-09-2019, 09:21
As far as girth goes, not all measurements are created equal. Not only does fill weight and baffling construction affect interior roominess, but different bags are cut differently from shoulder to waist. For example, WM bags flare wide at the shoulders in sort of a round bubble that narrows again immediately at the ribs, while FF bags go from shoulder to hip in a gradual taper. I always recommend lying down and rolling around in the bag before purchase. (If I manage to fall asleep in the store, I know it's a good fit!)

Tipi Walter
01-09-2019, 10:57
Look into Western Mountaineering sleeping bags. Pricey but you will not regret it.

Totally agree. Save money in the long run by buying quality right out of the gate.



At some point, even more down (like a 0F bag) gets too bulky unless you pony up for the high fill power stuff. I'd prefer not to have to get high fill power, since I live in the very humid southeast, but I don't know how I'd get a warm enough yet packable bag otherwise.

I do all of my backpacking in the humid Southeast and have been using high quality down bags for the last 40 years. Some nights are cold in moist air and the bag loses a bit of loft---other nights are cold in dry air and the bag regains its usual high loft.


I had the same issue with a Cosmic Down 20. It was simply not as warm as it should have been. I switched to a REI Igneo 19, which has the same comfort rating, and was way warmer. Same pad, same tent, etc.

One thing I did not realize is the Kelty is not 100% down, it is 16% polyester fill according to REI. I had a lot of problems getting the fill on the Kelty to spread out evenly. That poly fill may have something to do with it and the temp issues I experienced.

I now have several Western Mountaineering bags, and the difference is amazing. Quality gear really shows - my WM Alpinlite (20*) has 21 ounces of fill compared to the REI Igneo (19*) at 16.7 ounces. From everything I have heard, WM bags can last decades with proper care, so I consider these a long term investment.

No serious winter or cold weather backpacker I know of would ever consider getting a Kelty sleeping bag---sorry if this sounds harsh but Kelty bags are not on the top of anyone's list.



If you really are a cold sleeper, I strongly recommend either the 10 F WM Versalite or the 5 F WM Antelope MF.
Buy quality once.
Wayne

Couldn't agree more. Buy quality once. Esp for a sleeping bag---the single most important piece of gear for cold weather backpacking.

And then there's the perennial 15 DEGREE RULE---No matter what bag you get---it'll work to 15 degrees above its rating. EX: My -15F WM Puma bag keeps me comfy down to 0F. So if you're camping at 20F get a 5F rated bag.

The neat thing about an overkill down bag is it's both a Quilt and a Sleeping Bag. I use my Puma bag 90% as a throw over quilt---so I can toss and turn in comfort and still be warm at low temps. But here's the beauty of it---my "quilt" bag at 15F becomes a zippered mummy bag at 0F---something a true quilt cannot do. And you never know on a trip when your anticipated 20F trip gets polar and drops to -10F---then you'll need to go from a quilt to a zippered bag.

scope
01-09-2019, 11:43
... and not giving your body sufficient nights to adjust to your surroundings.
To the person who defined Western Mountaineering sleeping bags as tight fitting: Look carefully at the inner dimensions on their web site. I count 4 bags with a 59” shoulder girth. A fraction of the total offerings.

As I can't find another quote regarding the fit of WM bags, I assume you mean my reference to WM bags being "fitted". I feel you misunderstood my point, and as a result, misquoted me, though "tight-fitting" could be misconstrued as being synonymous with "fitted". As Zalman pointed out regarding the shape of WM bags, a "fitted" shirt starts out with similar shoulder dimensions and tapers through the torso. I wasn't speaking of shoulder girth only and was trying to make a point about the amount of material used, which WM uses less than the Kelty does due to the more fitted construction of their mummy bags. If you will actually look at all the specs, you'll see that WM doesn't have one regular size mummy bag with a hip girth as wide as 58", as is listed for the Kelty Cosmic 20.

orthofingers
01-09-2019, 12:21
Whatever you settle on for a bag or quilt, don't discount the amount of heat you can get out of a 1 liter Nalgene bottle full of nearly boiling water placed in a thick wool sock Or, one of those oxygen activated hand/foot warmers.

If I'm cold when I get in my hammock, even with my winter quilts, it can take forever for my micro environment to warm up enough to be comfortable. If I bring a Nalgene full of nearly boiling water inside a sock and place it next to my femoral arteries, I'm asleep within minutes and it's surprising how long that thing puts out heat, even on those long winter nights. I know, a Nalgene is heavy and boiling a liter of water uses up precious fuel (unless you use a campfire to heat the H2O) but, it works for me.

If I was starting on a thruhike in March, I'd plan to have a sleep system that would keep me comfortable down to the lower expected temperatures and a Nalgene or a few chemical hand/foot warmers for those unexpected lowest temperatures.

Tipi Walter
01-09-2019, 13:01
I agree with you on the Hot Hands solution---I never thought I'd go that route but last winter I started carrying hot hands packets and they work. (For us old geezers). On my upcoming planned January trip I'll be carrying 5 packets (10 pouches) of the things. I'm old and weak.

Regarding the hot water bottle---this last resort indicates your sleeping system is not right for the conditions you're facing. The bag is too light and the sleeping pads could be inadequate.

The last thing I want in my goose down sleeping bag is a container of water. Think about it---containers leak, even Nalgenes. There's always a chance tossing and turning could loosen the lid. And a wet down bag means the trip is either over or you'll be dead soon. I keep Water and Down as far apart as possible---but that's just me.

D2maine
01-09-2019, 13:10
Whatever you settle on for a bag or quilt, don't discount the amount of heat you can get out of a 1 liter Nalgene bottle full of nearly boiling water placed in a thick wool sock Or, one of those oxygen activated hand/foot warmers.

If I'm cold when I get in my hammock, even with my winter quilts, it can take forever for my micro environment to warm up enough to be comfortable. If I bring a Nalgene full of nearly boiling water inside a sock and place it next to my femoral arteries, I'm asleep within minutes and it's surprising how long that thing puts out heat, even on those long winter nights. I know, a Nalgene is heavy and boiling a liter of water uses up precious fuel (unless you use a campfire to heat the H2O) but, it works for me.

If I was starting on a thruhike in March, I'd plan to have a sleep system that would keep me comfortable down to the lower expected temperatures and a Nalgene or a few chemical hand/foot warmers for those unexpected lowest temperatures.

look into 40below bottles for this - way better than nalgene and they make great kozies for them...

Tipi Walter
01-09-2019, 13:45
look into 40below bottles for this - way better than nalgene and they make great kozies for them...

Those 40 Below bottles---made by Hunersdorf---are great if you love the strong stink of plastic in your drinking water. I had one for a year and had to ditch it due to the foul chemical smell. Beware.

44460
My Hundersorf bottle on a trip in 2015.

But I did figure out a neato way to add a cord loop to the thing---
44461

D2maine
01-09-2019, 14:12
Those 40 Below bottles---made by Hunersdorf---are great if you love the strong stink of plastic in your drinking water. I had one for a year and had to ditch it due to the foul chemical smell. Beware.

44460
My Hundersorf bottle on a trip in 2015.

But I did figure out a neato way to add a cord loop to the thing---
44461

washed mine a few times, no issue after that...weird yours did that..

Tipi Walter
01-09-2019, 14:34
washed mine a few times, no issue after that...weird yours did that..

It was so strong I couldn't stand it. "Very funky plastic smell" in this review about says it all---

https://www.amazon.com/gp/customer-reviews/R4IF0CXT0G62B/ref=cm_cr_dp_d_rvw_ttl?ie=UTF8&ASIN=B001OPJI44

Thing is, after soaking the bottle in baking soda solution . . . and then vinegar . . . it still stank.

Lnj
01-09-2019, 15:07
I sleep cold too. I just bit it last year and got a 0 WM down bag. It was a lifetime investment. But I figure that if I get hot, there are ways of cooling off easily enough. Just fluff it and let some air in to cool off, or unzip and throw a leg out, etc. But if you are cold... you are just cold and miserable and being cold makes me have to go to the bathroom, so now I'm up and outside and freezing even more... it's just not worth it to me. WM is a one and done solution, but it can't be done cheaply. Totally worth it in my opinion.

Tipi Walter
01-09-2019, 15:32
I sleep cold too. I just bit it last year and got a 0 WM down bag. It was a lifetime investment. But I figure that if I get hot, there are ways of cooling off easily enough. Just fluff it and let some air in to cool off, or unzip and throw a leg out, etc. But if you are cold... you are just cold and miserable and being cold makes me have to go to the bathroom, so now I'm up and outside and freezing even more... it's just not worth it to me. WM is a one and done solution, but it can't be done cheaply. Totally worth it in my opinion.

It's fun to see other backpackers learning the lesson I discovered back in 1980---get the best down bag you can find and scrimp on everything else. As you say, IT IS a lifetime investment---but it's more than that---it's the ticket price for a life outdoors in the winter mountains of North Carolina or Virginia or wherever you find yourself.

My first bag was a -10F North Face called the Ibex---and it lasted me 20 years of living outdoors on a permanent basis. Up until 2001---when I upgraded to a 0F rated Marmot Couloir. I remember fondly when I had to come up with the $320 to afford that NF bag---but without it I could not have lived outdoors in the NC winters. I think I have a pic of the beast when it was nearly new as I hitchhiked to Greensboro with my pack in 1982 and showed it off to my parents. (My pack is behind me).

44462

Getting hot in a zipped up bag is easily solved---unzip the thing and use it like a blanket. I used my North Face winter bag all year long and for all 4 seasons---just keep it off to the side.

Teacher & Snacktime
01-10-2019, 09:27
I sleep cold too. I just bit it last year and got a 0 WM down bag. It was a lifetime investment. But I figure that if I get hot, there are ways of cooling off easily enough. Just fluff it and let some air in to cool off, or unzip and throw a leg out, etc. But if you are cold... you are just cold and miserable and being cold makes me have to go to the bathroom, so now I'm up and outside and freezing even more... it's just not worth it to me. WM is a one and done solution, but it can't be done cheaply. Totally worth it in my opinion.

I so agree! I finally bit the financial bullet and bought a WM Puma (-20)!. My Kelty Cosmic Down 20 is now my spring - fall bag.

Time Zone
01-11-2019, 06:29
Just did some backyard testing, and found that wearing fleece PJs instead of thin long underwear makes a huge difference for me. A second ridgerest CCF pad may have helped too, but I've done that before and not noticed much difference (in warmth ... or cushion, ha ha). A tale of two nights:

40F overnight low. 1P tent (hybrid single/double wall), RR Solar (R 3.5), synthetic mummy EN comfort = 14F, Duofold thermals (poly inner, poly/merino outer). Was just adequate/cool ... not cold, but not warm enough to sleep soundly.

27F overnight low. Same tent, same bag. Added RR Classic (R 2.6) under RR Solar. Wore fleece PJ pants, fleece 1/4 zip pullover, instead of duofolds. Was TOASTY and slept soundly.

If I had a WM or FF bag of the SAME rating instead, could I have been toasty with just the duofolds? Possibly. But would that be because they rate conservatively? If not, what would it be? I don't doubt such a bag would be smaller and lighter for a given temperature rating. But if you are new to winter camping and aren't sure it's for you, what's the problem if you aren't ready to buy the very best bag possible? If your kid wants to learn guitar, do you buy them a Martin or Gibson right away? What's wrong with starting on a Yamaha?

Those interested in the relative effects of pad thickness and clothing worn on the insulation value of a sleep system (bag, pad, clothing) may enjoy reading the paper given by KSU's McCullough, Issues Concerning the EN 13537 Sleeping Bag Standard (presented 6/22/09). Interesting quote:


The data show that the insulation of the system components is not additive.

scope
01-11-2019, 08:38
Just did some backyard testing, and found that wearing fleece PJs instead of thin long underwear makes a huge difference for me. A second ridgerest CCF pad may have helped too, but I've done that before and not noticed much difference (in warmth ... or cushion, ha ha). A tale of two nights:

40F overnight low. 1P tent (hybrid single/double wall), RR Solar (R 3.5), synthetic mummy EN comfort = 14F, Duofold thermals (poly inner, poly/merino outer). Was just adequate/cool ... not cold, but not warm enough to sleep soundly.

27F overnight low. Same tent, same bag. Added RR Classic (R 2.6) under RR Solar. Wore fleece PJ pants, fleece 1/4 zip pullover, instead of duofolds. Was TOASTY and slept soundly.

If I had a WM or FF bag of the SAME rating instead, could I have been toasty with just the duofolds? Possibly. But would that be because they rate conservatively? If not, what would it be? I don't doubt such a bag would be smaller and lighter for a given temperature rating. But if you are new to winter camping and aren't sure it's for you, what's the problem if you aren't ready to buy the very best bag possible? If your kid wants to learn guitar, do you buy them a Martin or Gibson right away? What's wrong with starting on a Yamaha?

Those interested in the relative effects of pad thickness and clothing worn on the insulation value of a sleep system (bag, pad, clothing) may enjoy reading the paper given by KSU's McCullough, Issues Concerning the EN 13537 Sleeping Bag Standard (presented 6/22/09). Interesting quote:

Nothing wrong with starting with the Kelty. As I've tried to explain, its capable, but it needs help. There are several things that can be done to increase your body heat which will get the down in the Kelty to fully loft. Agreed with the more stout sleeping layer, both notable for lack of layers. If you're hiking and want to take less weight/bulk, then you simply find ways to create the heat you need to get the insulation to take you through the night. As many have said, the pad is integral because the bag doesn't insulate you on the bottom. Like many who've slept in a hammock without bottom insulation, it can get cold quick. I do think some components can be additive, but to what degree they are depends.

cmoulder
01-11-2019, 09:08
The data show that the insulation of the system components is not additive.




Context being everything, we don't know the basis for this conclusion.

However, as a stand-alone, blanket (haha) statement it is IME not correct: I have stacked a 50deg down summer quilt and a 40deg CS Apex quilt and slept warm at 14F.

Time Zone
01-11-2019, 10:51
Context being everything, we don't know the basis for this conclusion.

However, as a stand-alone, blanket (haha) statement it is IME not correct: I have stacked a 50deg down summer quilt and a 40deg CS Apex quilt and slept warm at 14F.
The author meant additive in a literal sense, as opposed to multiplicative, etc.
Here's greater context:


The insulation of the bag system can vary greatly depending upon which auxiliary products are used. To illustrate this point, a recent study was conducted where levels of clothing insulation, mummy bag insulation, and pad thickness/insulation were systematically varied to determine the effect on system insulation (McCullough, Zuo, & Huang, 2009). Data for synthetic bags are shown in Table 1 and data for down bags in Table 2. The data show that the insulation of the system components is not additive. In other words, a person cannot add clothing insulation and pad insulation to the insulation value of a bag measured according to Option #1 to determine the total insulation value of the system. Although linear and quadratic equations can be used to estimate the impact that clothing and pads can make on a bag system (McCullough, Zuo, & Huang, 2009), the individual insulation values cannot be added up with accuracy. Therefore, the insulation values for a sleeping bag system are more difficult to use in product development than data measured for the bag alone.



tl;dr: "It's complicated" (nod to Hail Caesar)

Your example is an interesting one. There's a formula that Enlightened Equipment appears to use for stacking quilts that adds the insulative value of the component quilts (vs. 70F baseline) to get at total insulative value. They would look at your down summer quilt as being worth 20 degrees of insulation, and your apex as being worth 30, for a total (additive) value of 50, which you subtract from 70 and get 20F. That you were warm at 14F would be a bit unexpected, by EE's method.

IDK about quilts in terms of the McCullough et al study, but that study basically found that the end result for sleeping bags is not the simple sum of the component parts - implying there's an interaction effect between bag warmth, bag type (down/synth), type of bedclothing (none, long underwear, or fleece) and pad thickness (0-2.5", by 0.5" increments). A quick glance at the data seems to indicate this effect can be positive or negative - the total insulative value may be more or less than the component parts, depending on the particulars.

This might relate to whether stacking sleeping pads produces additive r-values. Building insulation might be additive, but pads maybe not. Suppose you had four R=1.3 pads (e.g., klymit static v2) ... does anyone really think it would result in an R=5.2 level insulation if you stacked them and used them in winter? I don't. And the data suggests that the insulative value of going from a 1" self inflating pad to 2" self inflating pad is not double. Most of the insulating advantage is in that first inch of thickness, according to that study, anyway.

So it's complicated. One can read up and reason away, but our models of how all this works still reflect only a small fraction of the complexity of real-world situations. Right now, at best they can give us clues as to what some of the main drivers are. For me, it has been helpful to learn what a boost in comfort I get from fleece PJs versus regular long underwear. They found in the study that in terms of CLO value, fleece was 1.13, long underwear, 0.43. That's 2.6x as great. So that was a clue that I put to work in my system, and it really helped.

Time Zone
01-11-2019, 11:04
As many have said, the pad is integral because the bag doesn't insulate you on the bottom. Like many who've slept in a hammock without bottom insulation, it can get cold quick.
Yeah, it shocked me that hammocks needed bottom insulation below 70F ... until I experienced it!

In this case, there were (in the main) 3 independent variables moving. But it stands to reason that only 2 mattered - I was warmer at a colder temperature, so clearly the change in sleepwear and adding a 2nd pad were the key factors in improving warmth (lower temp could not have helped). What is left uncertain is how much the 2nd pad helped vs. the fleece PJs. I really can't be sure. I suspect the fleece PJs were the big factor, based on prior experience with 2 pads. But I could be under-estimating the effect ... that prior experience was above 40F. [I had done it previously to test comfort, not warmth - btw, it didn't help much in the comfort department!]. Perhaps at sub-freezing temperatures, that 2nd pad makes a bigger difference than I think.

Venchka
01-11-2019, 11:42
Without a few facts: weight, fabric construction, etc. the effects of youre clothing are hard to interpret.
Weight comes into play when you realize that a warmer, lighter bag offers a weight savings over extra warmer clothing.
I have a baseline clothing inventory for 3 season use in the Rockies from northern New Mexico to Jasper, Alberta between late August to early October. I can wear all of the clothing inside my WM 33 ounce, 20 F Alpinlite Long sleeping bag if needed. My current observed and measured low temperature with the minimum system is 15 F.
I can add warmer Merino wool long underwear, a 5 F WM Antelope bag and a generic CCF pad for moderate winter conditions.
And. The first down bag I ever purchased back in the 70s will perform similar to either of the 20 F WM bags currently on the market. The interior dimensions of the older bag match the Ultralite. I now prefer the extra internal space of the Alpinlite.
Wayne

scope
01-11-2019, 11:51
Yeah, it shocked me that hammocks needed bottom insulation below 70F ... until I experienced it!

LOL, and it shocks me that this is so, well, shocking. I mean, take your pad away from the ground at 80 degrees and see how cold you get. Doesn't happen as quickly as in a hammock due to breezes that don't exist on the ground, but rather, the ground ends up acting like a heatsink over time - like a waterbed with the heat out, if you've ever been unfortunate enough to experience that.

Its just so easy for folks to forget or just not realize that a pad's primary function is insulation.

Hikingjim
01-11-2019, 12:01
With some budget bags (around the 20-30 rating) and quilts, I've found down shift and placement can be an issue. Ie: if things move around, you'll all of a sudden have a really warm arm and no down on your core...
This is where shifting some down, making sure your bag/quilt is cinched right if possible, or doing something like laying a puffy on your core (as mentioned above) would help significantly.

If you're lacking loft in key areas and have some cold spots or spots in the bag where it feels like pretty well fabric only, you know you're going to have problems with lower temps

Agree that you just need something warmer though.

Had a friend on a winter trip freeze his ass off the first night and we had a good laugh after when we saw why (or at least I had a good laugh). His bag had continuous baffles, meaning you can shift the down around, and he was lying on top of 80% of the down and there was hardly anything on top!

OwenM
01-11-2019, 13:01
Off-topic, I know, but this thread drift is hitting on subjects near and dear to me(though I suppose that could be anything sleep system related!).

Context being everything, we don't know the basis for this conclusion.However, as a stand-alone, blanket (haha) statement it is IME not correct: I have stacked a 50deg down summer quilt and a 40deg CS Apex quilt and slept warm at 14F.
Agree, and I've used my 50F and 30F quilts together at 4F. Used my down hoody as a pillow. Was just experimenting, but this is something that I'd give some thought to if I were an early starter on a thru hike, since my two quilts weigh less than my EN 10F bag, and one could be sent home when no longer needed.


I mean, take your pad away from the ground at 80 degrees and see how cold you get....Its just so easy for folks to forget or just not realize that a pad's primary function is insulation.
So true, and summer temps with even an uninsulated torso length pad vs a tent floor will really drive that point home.

Time Zone
01-11-2019, 13:03
Just discovered multiquoting. :)


Weight comes into play when you realize that a warmer, lighter bag offers a weight savings over extra warmer clothing.

True, but I think we all recognize that weight and $ are a tradeoff for a bag of a certain warmth rating. If we instead ask (just making up numbers here), is a 20F, 2 lb, expensive bag warmer than a 20F, 3 lb, cheaper bag? IF both are consistently rated, they should be equally warm. So a lower end bag can work if you willingly take the bulk/weight hit. Dressing warmly enough and having a good enough pad should be equally important for both bags to achieve their rating. If buyers of higher-end bags are more consistent in doing that, it would not surprise me.

LOL, and it shocks me that this is so, well, shocking. I mean, take your pad away from the ground at 80 degrees and see how cold you get. Doesn't happen as quickly as in a hammock due to breezes that don't exist on the ground, but rather, the ground ends up acting like a heatsink over time - like a waterbed with the heat out, if you've ever been unfortunate enough to experience that.

Not a waterbed, but a pre-hiking years frontcountry camping experience with an inflatable mattress. Mattress, not pad - i.e., 8" thick, uninsulated. Mid spring in TN, not at elevation - froze! Yeah, heat sink indeed.

With some budget bags (around the 20-30 rating) and quilts, I've found down shift and placement can be an issue. Ie: if things move around, you'll all of a sudden have a really warm arm and no down on your core...
This is where shifting some down, making sure your bag/quilt is cinched right if possible, or doing something like laying a puffy on your core (as mentioned above) would help significantly.

If you're lacking loft in key areas and have some cold spots or spots in the bag where it feels like pretty well fabric only, you know you're going to have problems with lower temps

Agree that you just need something warmer though.

Had a friend on a winter trip freeze his ass off the first night and we had a good laugh after when we saw why (or at least I had a good laugh). His bag had continuous baffles, meaning you can shift the down around, and he was lying on top of 80% of the down and there was hardly anything on top!
My 20F goose down bag has those continuous baffles. I didn't even realize what that implied until recently, probably since it has not become too thin on either the top side or the bottom side. But I recently was checking out a 0F bag that had clumping/clustering down. By holding it up to a brightly-lit window, you could see the clumps and voids in each baffle.

The opposite of what you describe (with too little down on the topside) can be an issue too. If by design, a bag has most of its insulation on top (and I'm seeing this more), if you are a side sleeper and the bag rolls with you, your backside may get cold. If you can roll within the bag, you'll probably be OK but you may end up breathing into your hood.

Jayne
01-18-2019, 14:37
I recommend that you buy a 40 degree top quilt and just use it over the top of your bag initially. Then, when things start warming up in the spring you can ditch the top quilt and just use the bag. When summer arrives you can swap out the bag for the quilt. Most hikers understand the inherent benefits and flexibility of layered clothing but layering works just as well for your sleeping gear too.

ant
01-18-2019, 14:44
I recommend that you buy a 40 degree top quilt and just use it over the top of your bag initially. Then, when things start warming up in the spring you can ditch the top quilt and just use the bag. When summer arrives you can swap out the bag for the quilt. Most hikers understand the inherent benefits and flexibility of layered clothing but layering works just as well for your sleeping gear too.

This is very true. If you're interested in this approach OP, I may have something for you.

MattSin97
01-22-2019, 11:40
This is very true. If you're interested in this approach OP, I may have something for you.

Hey Ant, still figuring out my sleep system. What did you have in mind?

ant
01-22-2019, 13:38
Hey Ant, still figuring out my sleep system. What did you have in mind?

Send me a pm