I am trying to get some ideas of what works well for people when the mercury dips below freezing. Tell me what layers you have and what you like and what you would change about the system. I am still fiddling with my system but here is what I have for this winter so far.

Sleeping Pad - 3/8" CCF Gossamer Gear Thinlight on top of large Neoair

Base - light merino base layer

Insulation Clothing - none

VBL - AMK heetsheets bivy

Sleeping Bag - 0 degree down bag (undecided)

Bivy - Montbell Breeze Dry-Tec bag cover

So far the pad system seems to be working out well and is reasonably light and warm. I love merino and think it will always be my base layer. I am still trying to figure out the best way to use a VBL. I am considering VB clothing in lieu of a liner so I can wear insulative layers over it. I am undecided on the sleeping bag. Currently I am just using in my WM Highlite bag. That will change when it gets colder. I am also torn on the bivy. I feel it adds warmth to the sleeping system but seems perhaps overkill when used in a shelter. Is it a good idea to use a bivy just to protect from frost from outside?

Edited by Izeloz on 11/13/2010 20:34:16 MST.

Pad: Exped Downmat 7 full-length, 32 oz

Bag: 0F Marmot Never Summer 650 down, 3 lbs, 15 oz(!)

Baselayer: polypro bottoms, polyester top, dry wool socks, light polypro balaclava

Other clothing: add wool cap, insulating jacket as necessary

VBL: none
Bivy: none
Shelter:
- Golite Shangri-La 3 (with or without floor)
- Scarp 2 (double wall with mostly solid inner, extra poles)

I think a bivy is overkill in a decent shelter, especially in a double wall tent. I also think it would sometimes contribute to moisture build-up in the bag, and that would make VBL use more important. I plan to experiment some with bag VBL this winter.

In the Winter (0c to -15 C) I use:

Pad: RidgeRest (14oz) UNDER a NeoAir Small (9oz)
Bag: GoLite Ultra 20 Quilt(19oz)
Clothes: Down Pants (7oz), cheap but very Puffy Down Jacket (way too heavy...32oz) and thick socks.

Edited by dandydan on 11/14/2010 12:54:08 MST.

When the temps are forecasted in the single digits (F) I bring:

WM Antelope MF
Ridgerest torso pad
Full length Walmart blue pad
Shelter depending on terrain and weather

GG 1/4" thinlite pad - 4 oz
Bender insulated pad - 10 oz
Custom Nunatak Exp. quilt - 26 oz
Custom MLD Alpine Bivy - 14 oz
Custom MLD cuben SoloMid - 14 oz

Edited by thomdarrah on 11/14/2010 13:56:33 MST.

Temps below freezing:

WM Megalite bag
Prolite 4 full length pad
Powerstretch tights, microfleece zip tee
warm wool socks, fleece hat, gloves
Down sweater

Temps below 20 (F):
WM Antelope bag
Prolite 4 pad
same clothing as needed for comfort
add down booties if it's in the single digits
heavier down jacket when it's below 15 or so

Good down to the low teens for me, perhaps a bit lower:

- 72" long Neo-air
- two thinlight pads, 1/8" below the neo-air, 1/4" above it
- 20F rated WM sleeping bag
- feathered friends down booties
- Montbell Alpinelight down parka
- Capilene 1 longjohns plus normal hiking pants
- a thin balaclava (nice to keep my nose warm)

I like using the not-super-warm bag with insulated clothing combination; I don't tend to "hang around" in camp a lot, but still, it makes it a lot nicer when outside of the bag.

Edited by brianle on 11/14/2010 12:08:02 MST.

Here's what I used Tuesday night when temps dropped into the low 20's or high teens.

Pad - Pacific Outdoor Equipment Hyper Elite - 20 ounces
Quilt - EnLIGHTened Equipment 0 degree cuben fiber quilt - 20.9 ounces
Bivy - TiGoat with full net hood...with fabric hood pulled under - 9 ounces
Shelter - Zpacks Hexamid Solo without door - 8 ounces
Clothing - Same as I hike in, REI Sahara pants, thin mesh synthetic shirt, 9" boxer briefs, 2 pairs of liner socks
Headwear - Ray Way bomber hat

It was slightly drafty due to the winds and weight gain. I'm sure it would have been perfectly comfortable if I hadn't gained a lot of weight since buying the quilt. I wasn't cold though, just annoyed by the drafts.

I also had a blue foam sit pad that I put under my hips...not because I needed extra warmth, but because I wanted to try doing something useful with it.

Edited by leaftye on 11/14/2010 12:55:51 MST.

Interesting answers, but they would all be much more useful if weights were included! Especially for the bags/quilts and mats.

Cheers

Weights added.

From the bottom up:


1/2" Thermarest Ridgerest CCF pad cut to 3/4 length (8 oz)

Thermarest NeoAir Regular? (15 oz)

GoLite Ultra 20 Quilt Long (19 oz)

GoLite LS Drimove baselayer top (5 oz)

Silk bottoms (3.25 oz)

Montbell Alpine Light Down Jacket (? oz)

Western Mountaineering Flash Down Pants (7 oz)

REI liner socks (1 oz)

Goose Feet Down Booties (2.5 oz)

Fleece beanie (1 oz)

Downmatt 6

Montbell SS Down Hugger #0

I'll add the following when the temps dip below 0 F

VB socks and shirt

Fleece pants

FF down booties

Fleece balaclava

Montbell Down Parka

This is of course in addtion to my normal base layers and a fleece hat

Ridgerest regular 14oz
neoair small 9oz
golite 3 season down quilt 26oz
mb ul inner 7.25 oz
wm flash vest 4.95 oz
paty cap3 tights 6.3 oz
2 pairs of merino socks
blackrock down hat 0.9 oz
paty r1 hoody

slept very warm in this setup, should be ok in lower temp.

Edited by wwyjedi on 11/14/2010 15:56:42 MST.

Blackbird hammock - 18.44 oz

Gossamer Gear 1/4" pad - 8 oz (cut down for legs only)

Mamajamba Tarp w/Door - 20.9 oz

Winter Yeti Underquilt (5*F rating) - 21.5 oz

Winter Mamba Topquilt (0*F rating) - 26.25 oz

Smartwool midweight top/bottom - 14 oz

Montbell Thermawrap pants - 9.9oz

Colombia Fleece Jacket - 17.2 oz

Montbell UL Down Parka - 8.7 oz

OR Meteor Mitts - ?? havent weighed

Under Armour Balaclava - 2 oz

Blackrock down hat - 0.8 oz

Neoprene face mask - ?? havent weighed

Nunatak down booties - 3.2 oz

wigwam 40 below socks - 2 pair ??? havent weighed

Here's what I'm trying this winter for temps 0 - 20 F:

-Downmat 9 - 36 oz.
-Marmot Lithium, 0 degree - 2 lbs. 15 oz.

(Wow, this is heavy so I hope I stay toasty warm!)

-MLD Superlight Bivy
-GG SpinnTwinn (if snow/rain is expected)

From this recent thread on Exped mats:

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=39138

Ken had some excellent posts, including the following EN standards:

"To remain thermally neutral at the following temps the corresponding r values must be used with a proper EN rated bag and a light baselayer.

0 degrees=7.0r
10 degrees=6.0r
20 degrees=5.0r
30 degrees=4.0r
40 degrees=3.0r
50 degrees=2.0r"

Similar stats have been posted in the past, IIRC, by Mr. Nisley.

My experience has been pretty equivalent to the above numbers, including plenty of time in the -20F to 10F range.

A Neo plus a Thinlight is something like R-3 to 3.5, ie half of the thermoneutral value for 0F. In my experience, I've found that R-8 is necessary around -20F to 10F (R6 acceptable at 10+), & a Downmat 9 works great (R-8). Have also used a standard Thermarest w/a ridge rest quite happily (~R-6). If the pad isn't warm enough, the rest of your system (including you) has to work harder to stay warm. Not saying that it isn't possible to use a lower R-value pad in such temps, but that it is unusual for that lower R-value to be sufficient for most people.

Also note that when sleeping bags are rated at a given temp, they assume an adequate amount of insulation underneath them, as above. In other words, if you have a negative 20F bag on a thinlight in +20F weather, you'll probably be cold.

Just to clarify from the OP, that no insulating clothing bit was specifically for the sleep system, right, but you would have insulating garments in your pack?

One other note, on the large Neo... the wider pad w/a narrower bag can result in some additional airflow/heat loss. I talked to someone at Cascade about this & they agreed... better in cold to have the sleeping bag pretty much covering the pad.

Interesting, Brad. I guess that means one sleeps on frozen ground or rock, for those number?

My experience is that when camping on top of snow, an R Value of between 4 and 5 is sufficient, reason being that the temperature of snow is at the 0 C mark. Hence I don't bring a Downmat or similar heavy equipment when I will be sleeping on top of snow, a Multimat Adventure and a Artiach Skin-Micro Lite are more than sufficient for that.

Btw, not UL but excellent for snow camping: Reindeer fur!

I think those ratings are useful, but also a wee bit cautious (they probably don't want them going the other way!)

I've used a neo air several times at or slightly below the freezing mark w/ no discomfort (I sleep a little warm so maybe that's some of it), according to the EN chart I should have two Neo's. I've also got by into the mid 20's w/ a neo and a 1/8" thinlight- again contrary to the EN ratings.

I think the ratings are useful, but some (probably not all) might find them a little on the cautious side- which is a much better scenario than the opposite :)