Are bag temp raitings accurate?

“When a manufacturer posts a temp raiting on a bag, does that mean you would be warm at that ambient temp with cloth on or off inside the bag. I'm about to buy a bag, for nights that could get down to about 15-20+ but, I don't want a bag that I would have to wear my coat it to be warm. So what temp should I get?”

“I think it is a crap shoot. The only bag I have had that was close was a North Face manufactered off label, synthetic bag. I vote buy a grade colder and unzip if you have too. I hate sleeping too cold, but can always vent enough to cool off.”

“You need to check with each manufacturer to see how they come up with the rating. There is no uniform standard that I know of. Maybe some one else came tell us if there is a standard. I know of one manufacture that states that they assume that you are in a tent and wearing long underwear, socks and a hat. They also warn that people vary widely in the amount of heat they generate while sleeping. I would be suspicious of any company that would not or could not provide an explanation of their ratings. The ratings are most useful in comparing bags from the same manufacturer, not for comparing bags from different companies. For different companies use the rating along with the specification for the fill, the loft, the arrangements of the tubes and protection of openings to judge. Most shops have weights so you can try on packs with weight in them, maybe they need a walk in freezer so you can try out the bags in the cold.”

“My understanding is that a bag rating is what will keep ou alive. You may not be toasty warm, but you will not freeze to death. IN my experience, a 15 or 20 degree bag is sufficient for just about anything except winter sleeping. If your bag is too much, you will be unhappy much of the time. I have a friend who went out and bought a 0 degree down bag which he uses primarily for 3 season camping. He is always sweating his ass off. If you are cold, you can always put on clothes or purchase a liner for your bag to bump up the rating.”

“My down bag is a sem-rec and rated at 20 degrees. I don't feel it kept me warm enough. I'm not exactly sure what the temps were that I was camping under, but it had to be between 25-35 degrees. I had to wear all the clothes I brought.

If you won't use the lower degree bag that often, buy the fleece liner.”

“They are VERY accurate!
I bought a TruValue brand bag for $11.00 from Rufus' Gear Supply and Radiator Repair in Pinestump, GA, that is rated for 50 degrees. At about 49-1/2 degrees, I kinda catch a chill, especially if it's a bit "airish" that night.”

“I did a test in the backyard a couple weeks ago. Read on if you want to see what I found.

It was expected to get down to +5 or 0. Very little wind, no precip.

1st night I used my 20 degree TNF Blue Kazoo, and wore all the clothes I would normally bring for a spring or fall trip. REI MTS midweight longjohns, top & bottoms. Sportif Supplex pants and long sleeve shirt. EMS polartec 200 vest. Thorlo hiker socks, Military surplus wool watch cap. I fell asleep easily and woke up several times, but not from being cold. I was just on the lower edge of comfortable. After using the bathroom near dawn, I checked the thermometer and it read +3.
Summary: my spring/fall setup is easily survivable down to 0.

2nd night identical weather. I used my -5 degree TNF Serac and wore only boxers. I fell asleep easily again and woke up several times to find myself very warm bordering on sweaty. The thermometer read 5 when I got out much later than the first night, about 6 AM.
Summary: -5 degree accurate, will use up to +10 or so.

I think this shows, that for me, the bag ratings are fairly accurate. I've been told I sleep warm by females who in my xperience all sleep colder. Take it for what it's worth...
Craig”

“I forgot to say but both nights were out in the open and on a ridgerest deluxe pad.”

“Some are closer than others, but I'm not as dedicated a gear tester as Le Subtil.

My formula to be on the safe side is , pick the lower end of the temp range you are in most,go down another 10 deg.

Lots easier to get cooler than get warm after getting too cold.”

“I got a +5 degree Slumberjack about 8 years ago. When it was new, I could be comfrotable down to about 10 degrees. Now it rates around 30 degrees. BTW, It's a synthetic.
I just ordered a 0 degree Down bag from Campmor. I'm looking foward to getting it out in some COLD temps to try it out.”

“I'd have to agree with Pathman. Personally I am a cold sleeper so I have a warmer bag and when I need to I unzip. that is until the summer and then any bag I have is to warm and I usually sleep on top.”

“If I expected temps to get down to 15 I would go with a 0 degree bag that has decent venting options. But I'm a very cold sleeper.”

“I have a Slumberjack rated for zero and I get cold at 20 degrees. I'm a cold sleeper.

LeSubtil, It must have been you that kept us all toasty warm in the tent at Pictured Rocks. :o)”

“No they arent.”

“I want to hear everyone sing the Star Spangled Banner. We live in America. Buy a bag, save your receipt and try it out. If you freeze your @ss off return it for a full refund and try someone elses product. Where else in the World can you do that?

God Bless America”

“I think I'll get a red, white, and blue slurpee.

Don't you hate businesses that fly the flag in the rain? It's been raining here for a few days, and places haven't taken the flag down.”

“Backpacker Mag in it's annual gear guide points out you can only use the temperature ratings to compare bags by the same manufacturer. Rating's haven't been standardized, yet. I seem to recall that a good guide is 10 degrees warmer than what the bag rating is.”

“bacpac just wraps his hairy self in the American flag and stays nice and warm.
That would not work with ANY other country's flag.
Dog bless Amerika!”

“I agree with roseymonster, I've been told (and also experienced) that the temp rating on the bag is a survival rating, not necessarily a "comfort" rating. Hence my move from a 15 degree down bag (which I froze my @ss off in at 28 degrees) to a -15 degree bag. The extra $$ were definitely worth it! I've been happy with my LLBean -15 degree bag at temps down to around 20 degrees. Haven't had to test it lower (thank goodness!)”

“About the temp ratings being a "survival" rating: if this is true, it's probably just a legal technicality to cover the company's butt, putting them on the extreme safe side (anything less than death at any given bag rating & equal or greater outside temp is not grounds for liability.)

Here's my experience with two different bags:

1. In my Slumberjack synthetic 20-degree bag, I froze in 25 degree weather in escalante. Wore thermal top/bottoms, fleece hat.

2. In my North face down 25-degree bag, I've been toasty in 20 degree weather in the wind rivers. Wore t-shirt/boxers.

Both instances were in a tent with mild breezes. From this I gather that the North Face is more conservative with their ratings than Slumberjack.”

“Plus factor in what you had for dinner, how hydrated you are, do you need to make a call of nature, etc. Other factors are involved, of course.”

“If you eat good before going to sleep, you will sleep warmer. Plus I usually wear a balaclava if it's real cold to keep even warmer.”

“I used to sell gear...
way back in the 80's
I noticed a lot of references to wearing clothing in your sleeping bag. By restricting your body heat with clothing you actually cause the bag
to sleep colder. Try it
...it really works. Less clothing = more body heat released into the bag which is designed to insulate and utilize your body heat to keep you warm.

I have a 20 year old Camp7 Goose down bag that was rated at +5
I have never been cold in it even when snow camping. On the other hand in mild temps it will cook you! I just sleep with it unzipped
and draped over me like a blanket in those situations.”

“I've tried that before WW. It seems to work some but I start getting cold after a while. I wonder if that's a difference between Down & synthetic. I'll be getting a Down bag this week and I'll compare them.”

“Maybe so....walkindude

Most of my gear is 20+
years old and I've noticed some of the brands I used to sell
have disappeared like... Camp7 and Wilderness Experience,Sierra West, Etc. But many are still going strong
Marmot, North Face, Kelty, etc. I have also noticed many new ones .

I owned a small backpacking shop in my home town....got most of the gear I have now
wholesale :)

The only new gear I have purchased is a couple of bear canisters and some trekking poles.”

“Wind Walker, you'll never get in the Gear Heads Anon. club with that attitude! More gear! More toys!”

“Actually I did buy a Pur water filter and a new MSR stove a couple of years ago....I guess that still wouldn't qualify me for gear heads annon....hmmmm.”

“Bag tempretures are relative, they are rated on the average sleeper by a very sophisticated peice of equipment. how warm you sleep, how accurate the ratings are, depends on you.
I have a son wh would freeze in a 0 deg. bag at 65.!!!”

“As a trailguide in a previous lifetime (@%#dangit!!), I concure with some here that temp ratings are pretty specific within the products of individual companies. The happiest sleepers seem to be TNF bag owners, I've been a Slumberjack bag owner most of my years and have found that even new they seem to be off AT LEAST 10 (more like 20+ after a cupla years use) degrees. Now mine is Hollofil II, so I'm still in fill that is WAY outdated, but that'll improve within the month.

I'll likely make my own in the next 4 weeks, either fleece or down. But I'm my eyes are peeled for decent priced (yeah right) Mountain Hardwear 2nd Dimension Stormlight or Feathered Friends Lark Lite (prefer the PTFE laminated shell). Both are rated at 10deg and are down-filled. I've heard (not experienced) lotsa good remarks about both these companies. Anyone remember what JerBear had that compacted so small?? I believe it was a 10deg down bag also.”

“null”

“Hey Nekkid - that would be a Marmot Arroyo, JerBear's 30* down bag, of which you speak. Or perhaps he has another that is a 10*?”

“Good God! You live CP!!! Thanx gal, but if JerBear had a 30* bag at Savage, he Da Man! Now of course he IS Da Man, but I'd still be doubly impressed if his bag there was a 30*er. Sat night it was 18*, and we were camped on a bit of an exposed rigde/cliff top where a bit of a breeze passed about us thru the night. So 30*? I do suppose I've not taken into account his "geothermal" heat source, thatta' heated his tent up some!”

“i had a 20* TNF bag that was almost 30 yrs old, at savage gulf.”

“Yo N Ape, What are ya gonna call your line of Sleeping bags? The Nekkid Sack?”

“My hats off to ones who are still getting good service from 20 and 30 year old (down) bags I presume. My first down was purchased in 70 and got so clumped up I retired it at 20 years.”

“Now that's still pretty damn impressive to get that kind of life out of a bag!”

“Consumer Reports did an article on it several years ago.

A specially designed mannikin is heated to body temperature, inserted into the bag, and the bag placed in a controlled temperature room. Sensors on and in the mannikin record the rate of cooling. From the heat loss rate the temperature rating is derived. I cannot say if all manufacturers test their bags with this method.

The ratings are all subjective, as individuals have different comfort levels and metabolic rates.

The old wive's tale about naked is warmer is bogus. A set of clean thermal underwear is additional insulation. Dirty clothes are cooler, clean is warmer.”

“Naked Ape. I have a 2nd Demension but it isn't down. It is Polarguard 3D. I think Mountain Hardware's Down Stormlight is the Tallac. Here is a Moonstone 3D filled bag on clearance. I like the 2nd Demension. It worked great at 28 deg. I haven't had the oppurtunity to try it at it's rated temperature. I think it is 15 deg. Here is a Tallac on sale. It isn't the stormlight fabric though. You could probably find one cheaper somewhere else on the web.”

“A few more sales

Mountain Gear

And don't forget Walkindudes deal

A few Marmot Bags”

“Ape 30deg bag I have! Thats all you need! Go for it! Hi CP, You doll! WD, sleep naked! LOL”

“I just bought a 15deg. bag from North Face through Campmor. 800 fill down and only $199.00 A little pricey but, it was listed at North Face's site for around $380.00

Check it out.http://www.campmor.com/webapp/commerce/command/ProductDisplay?prrfnbr=5907531&prmenbr=226”

“Iv`e got a little 40 deg. blue puma bag down of course thats 25 years old and still is like new

how`s that”

“Nekid is warmer...
That's my story and I'm sticking to it!!!
I always tell my wife if we zip the bags together and sleep nekid we will sleep warmer. ;) It has always worked so far!!!”

“Very nice theory Wind Walker - I guess it must be working for you! ;-) Have you consulted Lipstick Hiker on your idea? She had some definite opinions on any "funny stuff" being allowed in sleeping bags! ;-)

Anyway, I've found it's better to either strip down or put on fresh long undies (and socks) for sleeping. For sure don't try to leave the socks on that you've been in hiking all day!

BTW, women tend to sleep colder as a rule (if they're sleeping alone that is!).”

“IMHO, aswell as what research I have come up with most DOWN bag Mfgrs, suggest a bag liner or a skin of clean clothing. A dirty Down bag sleeps colder!Also heavier! YO!2cents”

“Super thanx y'all!! I'll give those a lookover baume, great thanx! Yeah JerBear I want at least a 20 degree bag, if not a 10* one, one that I can afford that is. I plan to get a liner as well, mebbe I ought to begin a bag liner thread, I'm very interested on what y'all thank of one. I've not had the pleasure of a liner thus far. I would want one with a down bag for sure, for inside the bag at cold temps, and on top of the bag in warmer temps. I'd like a supremely compactable down bag, and light liner (silk or Coolmax or something), to go with my Bivy Sack.

LOL WD! I'll hafta come up with a good name if I make my own, I reckon'.”

“Good gravy, I just noticed that the 2nd Dimension is NOT down filled, but has Polarguard 3D. Whilst I drool, can anyone tell me how well P-guard 3D compresses? Thankee again baume, that's one I'm looking to mebbe buy. And even better, the short one is for 5'7" ppl like me (shewt dat even gives me an inch storage) and weighs nearly a half lb lighter.”

“Mr. Ape...I have both a 2nd and 3rd Dimension that I got (both) for ~$105. I wanted the 2nd dimension but the deal was soooo good I couldn't pass up the 3rd Dimension 30F also. I've ended up using the 3rd the most of all my bags.

MH gives you a waterproof stuff sack ~8"dia x 16" length, but the bag will fit into a smaller stuffsack. My bag does not have a draft collar, and weighs in on my scales as 2lbs 13.8oz.”

“I also have a NF 800-fill 5F bag (wieghs in @ 3lbs even...stuffsack included) similar to the one Mr. Air mentions...it's the one that I used this last weekend in the Catskills.

At 10F, the inside of the pab felt cold to the touch...and I stayed warm enough to catch some Zzzz's.”