Best light synthetic 15-25F sleeping bags

I assume that you want a synthetic bag for its ability to retain its insulation value better than down when wet rather than its initial lower cost. Polarguard Delta looses ~40% of its insulation value when wet but it has the best the weight to insulation value ratio of any synthetic. Primaloft sport looses ~15% of its insulation value when wet but it has one of the worst weight to insulation value ratios.

I suggest a Primaloft sport bag in the 40 degree range rating (~1″ loft and ~2 lbs because it is the most impervious to moisture and packs as small as a down bag. Augment it with what ever clothing insulation you would normally use for those temperatures. You will need about another 1″ of clothing insulation for 15 -25 degrees.

This arrangement more safely allows you to use down or Polargaurd synthetics for your clothing insulation. Down would be the inner layer of the composite sleeping solution and so the moisture would migrate out to the outer synthetic bag.

Also, take a look at the Montbell SuperStretch BurrowBag #2 – regular length for your wife; long for you. Using base and mid layers (no high loft insulating layer), it’s a 20deg bag for a cold sleeper (me). It’s rated as low as 5degF, but that’s perhaps unrealistic for all but the warmest of sleepers also wearing hi-loft top and bottom.

If you are a warm sleeper or intend to wear all of your insulating clothing in the bag then maybe the warmer and lighter BurrowBag#3 might be a better choice?

Not saying that the MB bags are better than those you are considering (I have no experience with the 2nd Dimension bags), I’m just recommending them per your request for additional recommendations to consider.

I own only one MtnHW bag – Lamina 45. Fine bag, IMHO. Wearing some clothing, it’s a 45deg bag for me. I have only one TNF bag (Equinox a Mfr claimed 35deg bag, but it’s really a 45deg bag for me). So compared to the Lamina45 (an accurate Mfr rating as far as my use is concerned), the TNF Mfr rating is overrated. Can’t say that this is so for all TNF bags though – I only have the TNF Equinox. Other than the temp rating, the Equinox is a very nice bag with more features than in some other similar bags I am familiar with.

You will be a hikersicle if you use anything else. All his competitors are braindead!

Polarguard Delta … has the best the weight to insulation value ratio of any synthetic. Primaloft sport … has one of the worst weight to insulation value ratios.

I am guessing that Richard is referring to Polarguard Delta having a better thickness to weight ratio than Primaloft. Which is correct.

But, the clo-values/oz provided by their respective manufacturers (as reported at thru-hiker.com) say that Primaloft provides 8-9% more insulation value per oz (.74 vs .68).

I’ve heard a lot about Wiggy’s gear. Never have used any. Looking at the specs, some of the sleeping bags seem pretty heavy, e.g. 3.5lb for a Wiggy’s Ultra-Light Summer bag. What am I missing that makes this bag a good one? I have a 23oz summer synthetic bag.

Heres or reason or fifty not to deal with Wiggy.

Its distasteful to read, but very illuminating.

http://forums.kifaru.net/ubb/ultimatebb.php?ubb=get_topic;f=4;t=000200
http://forums.kifaru.net/ubb/ultimatebb.php?ubb=get_topic;f=4;t=000491
http://forums.kifaru.net/ubb/ultimatebb.php?ubb=get_topic;f=3;t=001841
http://forums.kifaru.net/ubb/ultimatebb.php?ubb=get_topic;f=1;t=000965

Also look at TNF Fission and Orion bags. The Fission has a Delta insulation and a 1/3 zip; the Orion has Primaloft Sport and a 2/3 zip. Published weights are 2 lb. 4 oz. and 2 lb. 6oz., respectively; my Orion weighs 2lb. 5.1 oz on my scale. I bought the Orion for greater compressibility and the longer zip. For some reason I felt claustrophobic with the 1/3 zip of the Fission and wanted the greater temperature range a longer zip would provide.

Are a contradiction in terms – for the weight of the lightest Wiggy bag you can carry four down bags or two quality synthetics; this doesn’t take into account the sheer massive packed size of Wiggy bags, which will no doubt push you into big/heavy pack territory.

I know you said you wanted a mummy, but have you considered a synthetic quilt? I use a down quilt that I am pretty happy with, it’s as roomy as you need it to be and it lends itself to layering to get you to lower temps when necessary. The quilt design is also effecient as there is no bottom insulation, which would help with the extra weight and bulk of synthetic insulation.
Fanatic Fringe has ready made quilts in several flavors of synthetic insulation. They are pretty narrow, but for a small charge they will make you a wide one.
Ray Jardine will sell you a kit to make your own quilt. These are somewhat customizable in that you can add extra insulation or extra features as you like.You can make a double quilt for the two of you which seems like it would be even more effecient weight wise. It looks to be a fairly easy project, even for a novice sewer.
Tom

Donald, thanks for the info and your experience with the TNF bags. I’m filing that info away for possible future use. It’s good to know that for some reason my Equinox is atypical for TNF bags.

Looking at the Fill Wt. for the TNF Fission, in my case, i don’t think that I could get it down to 20deg F, perhaps others could. It has 25oz of PG Delta. My MB SSBB#3 has 25oz of Exceloft, but making up a bit for PG Delta’s claim as being more thermally efficient (I’ll accept that claim even having no comparative test data) is the fact that the MB bag is 2″ shorter and can possibly have 1″ less shoulder girth if the superstretch is relaxed. For me the MB SSBB#3 is a 30degF bag.

I bought on clearance, dirt cheap and couldn’t pass it up, quite a while back a MtnHW Trekker (67″ long), rated to 20degF, and it has 27oz of PG 3D – I’ve used this bag a lot and even new it was 25degF bag for me with just base and non-lofting mid layers.

I’m guessing that the two TNF bags you mentioned would be 30deg bags for me – not bad at all given their lighter weights than what I currently own and use for those temps. I’m impressed with your suggestions.

I didn’t see any LOFT figures for TNF bags on their website, maybe I missed it? But if it truly has 5″ (standard for a 20deg bag) of recovery loft (i.e. let’s say 30minute recovery after stuffing into its sack), then I’ll buy that it is a legitimate 20degF bag for an average to warm sleeper (not sure which, i.e. avg. or warm) with at least base layers on.

I sure do like the features in the one TNF bag I own and if someone can get them down to their Mfr Temp Rating, they are light wt. cp. to many of their competitors. The hood designs of the TNF bags (at least my Equinox which looks identical to some other TNF bags in hood appearance/shape) are great also, perhaps(???) only surpassed by Marmot hoods (just based upon reading other’s experiences – I don’t own any Marmot bags).

Appreciate you taking the time to make your earlier Post and share your personal experiences.

The MH 2nd dimension was my first bag…and I only used it for backpacking about 3 times before replacing it. The thing is HUGE. It does all it is supposed to, but it is simply too big and heavy. It is now the car camping/spare sleeping bag.

Hi Paul,

Good points. Just because some folks can sleep in a Fission down to 20F doesn’t mean you or I can. In any case, check out this discussion of the Fission from last September:

http://www.backpackinglight.com/cgi-bin/backpackinglight/xdpy/forum_thread/1217/index.html?skip_to_post=7472#7472

While you’re there click on Anatoly’s link for the European EN 13537 standard. Lot’s of good info in there.

Jim, You said ,” But, the clo-values/oz provided by their respective manufacturers (as reported at thru-hiker.com) say that Primaloft provides 8-9% more insulation value per oz (.74 vs .68).”

.74 is the correct Primaloft Sport clo/oz but .68 is not valid for Polarguard Delta according to my calculations. A while back I searched for many days and couldn’t find the clo/oz values for any of the Polarguard products so I invested a lot of time to calculate them myself.

After your post I searched the Thru Hiker Web site and couldn’t find the Polarguard Delta .68 clo/oz value listed. Where did you find you find your Polarguard Delta clo/oz?

My calculations showed the Polarguard Delta clo/oz to be approximately 1.467 and the less thermally efficient Polarguard 3D to be .909.

A few months after I did my calculations, I read a research report done by Hes L: Effective Thermal Resistance of Fibrous Layers Used in Sleeping Bags: In: Internat. Conf. Textile Science, TU Liberec 2003. Page 254 of the report shows the Polarguard 3D lamda value of .0421 which corresponds to a clo/oz of .909. Since this matched what I came up with I am also pretty confident in my Polarguard Delta clo/oz value.

Richard:

Do you know if there any difference in the clo/oz value between Primaloft Sport and Primaloft One?

Thanks.

Richard-

I’m working on an article about sleeping bag insulations for BPL right now. I’d be very interested in finding out more about your calculations and research. If you’d like to share, please contact me off-forum at michael (at) backpackinglight (dot) com.

Thanks!

Integral Designs Renaissance bag. With 3 inches of loft, rated to 20F, plus the outer shell is Pertex Microlight. Regular size is 2lb, 14 oz; long size is 3 lb, 4 oz.

Primaloft Sport is .74 clo/oz. Primaloft One is .84 clo/oz.

Thanks Richard! Interesting that Primaloft One isn’t as thermally efficient as 3D and not as durable too, but a lot of manufacturers still use it. I suppose for really wet environments, it still makes a lot of sense.

Thanks for all the great feedback everyone. Very helpful. Are there any other specific models in the 15-25 or 30 range that anyone would like to recommend?

Dane, Which synthetic bag did you choose to replace your 2nd Dimension?

Anyone know if the Excelloft used by Montbell in their synthetic bags and jackets is Primaloft Sport or Primaloft One or something else?

Exceloft™ insulation uses 8-denier polyester threads as a structure to intertwine with extra thin 0.7-denier threads that add more air pockets and resilience. As a result, Exceloft™ products rival the warmth and weight of down products. Exceloft™ excels in wet conditions: because the fibers used in Exceloft™ retain less than 1% of their weight in water, Exceloft™ will keep you warm even when wet.

Exceloft™ insulation uses 8-denier polyester threads as a structure to intertwine with extra thin 0.7-denier threads that add more air pockets and resilience. As a result, Exceloft™ products rival the warmth and weight of down products. Exceloft™ excels in wet conditions: because the fibers used in Exceloft™ retain less than 1% of their weight in water, Exceloft™ will keep you warm even when wet.

Exceloft is montbells own proprietary insulation, not made by primaloft or any other insulation company

Thanks Ryan. I was going to give Montbell a call but you beat me to the punch. So many times outdoor industry companies buy the same material and just rebrand it. Some companies, like Patagonia and Arcteryx, will pay more to use the material first for a year or two and brand it with their proprietary brand name, before the same material is released to other companies (and then often sold at a lower price).

I’ve heard nothing but good things about Montbell products. I’m looking forward to picking up their UL synthetic parka made with Exceloft.

Any other specific bag recommendations out there?

“Integral Designs Renaissance bag. With 3 inches of loft, rated to 20F, plus the outer shell is Pertex Microlight. Regular size is 2lb, 14 oz; long size is 3 lb, 4 oz.”

I’ve had the same dilemma and this is the best I have seen for this class of synthetic bag. They sell for ~$200. Good tip.

The ID bag has two layers top and bottom— I wonder what could be done with synthetic bags by using one material on the bottom and another on the top– picking crush and water resistance for a single bottom layer atribute and a lofty double layer for the top.

I was on more of a budget myself and went for a Sierra Designs Wild Bill which is rated for 20F and I’m assuming that may be optimistic. It was just $61 on Ebay for a new 2006 model. The regular length is 3lb4oz.

It seems all the 20F bags are in the 3 pound range, give or take a few ounces. I was also attracted to the specs on the Kelty Light Year (25F though) and the Slumberjack Ulitmate bags for economy bags in that temperature range. That is all armchair comparisons to temp rating, weight and price– no hands on at all.

Someone mentioned wind resistance and I can vouch for that. I did a night of sleeping bag testing on my front porch which is covered but otherwise open to the prevailing winds. I started with a Lafuma 800 Extreme, rated at 37F and It felt like is have enough insulation, but the fabric let a lot of cold air through. Having it inside a tent or bivy would make all the difference. I bought as a summer bag, so the breathability will be a plus there.