I've got a 20F rated Golite Ultralight Down Quilt, I'm a very warm sleeper, so we'll assume 20F with it is not a problem for me.

I'm wondering what combining this with a 20F rated down sleeping bag could get me down to?

Anyone have experience combining bags and or quilts like this? I'll probably be using a z-lite and a pro-lite combined as my pads.

thanks!

Steve,

I have been doing this for over a year. In cold weather I use my Tim Marshall cuben quilt inside my Nunatak Arc Specialist. Gives me 3.75 inches of loft versus 2.5 inches in my WM Ultralight bag and the dual system weighs less. My Nunatak is much bigger than the Marshall quilt, so there is no compression. For me it works very well.

Someone posted a formula a while back to calculated the temperature rating. I think my system came out to 6F. But that means little, because I sleep very cold. I have learned that pad R-value is really, really important. Last year I got a BAC insulated pad and with a 3/8 or 1/2 foam pad in snow I am now a happy sleeper.

The other big thing I learned from Roger Caffin is to use a sufficiently insulated balaclava in cold weather.

I had cold weather hiking, but do more of it now.

cool, I purchased the 20F bag, don't know what the loft on either is (neither is advertised), so I'll see what I get out of the combo!

Steven, your quilt over your 20 F. down bag should be good to at least 0 F. with medium weight long johns and a balaclava.

I'd bet it could be comfortable to -10 F. but only if you have elastic straps on your quilt that go under your mattress(es) to keep the quilt close against your bag and cut heat loss.

Put your zipped up mountain parka over your bag & quilt foot area so they are INSIDE your parka. Also cinch up the parka's hood. This adds warmth and keeps your bag dry if its foot touches the frosty shelter fabric.

For more warmth lay your pants and shirt flat beneath your mattress(es). Every little bit of insulation helps.

excellent. I do sleep silly warm so that should do me well.

I was thinking quilt over/around the sleeping bag?

I have a Prolite 3 Regular and Short and a Z-lite Short as pad options, I'm thinking take the Z-lite and Prolite Regular. One of these days I'll buy a proper insulated winter pad =P

won't I have freezing issues if I lay the pants and shirt beneath the mattress?

at least -18F and my I had to wear my down booties started with a boiled water nalgene, otherwise fine! the nalgene got to body temp rather quickly though.

Edited by TinCanFury on 01/15/2012 20:52:54 MST.

Steven,

I believe you can get lower with a 20F bag+the 20F Down Quilt.

I picked up the Golite Ultralite Down Quilt a few years ago on their clearance sales in town and I used it in conjunction with a +50 synthetic BA Lost Dog while climbing Blanca and Ellingwood in Colorado during March (my birthday) above 11K-- the temperature was zero degrees, my friend recorded -3degF-- so give or take for margin of error.

Underneath I had two CFF pads.

I would say that with the 20 quilt + 20 bag should take you into the negatives at least-- the big problem however is the drafts, with a quilt you have no protection without a draft collar. I was warm, but did not sleep comfortably and quickly ditched this two bag system and purchased a WM Kodiak that would was more suitable.

Personally, I think that double bagging works to about 10-15degF, but would I do it again for true winter climbing? Hell no, invest in a real zero deg bag. I also upgraded my pad system-- Exped Downmat 7 or 9 depending on conditions. UL/SUL/LW etc works well, until a point--- winter is a different ball game.

now that I have some time, here's a full writeup of my experience. Keep in mind that I'm a *very* warm sleeper, especially when I've just at a decent sized meal.

For our cold night we were in a lean-to, with 3 wall draft protection and not a lot of wind that night, but every so often you could feel a breeze.

For pads I was using a Z-Lite Small and a ProLite 3 Small with a slight overlap where my hips are. I also have my therm-a-rest pillow since I'm a side sleeper. My bottom facing side was never cold for longer than a few minutes when I would "toss" around. I would prefer having better R-rated full length padding for these temperatures. A Exped Downmat, Kooka Bay, etc., or even a NeoAir with a mylar sheet may be enough for me?

We got to 'bed' by around 7pm, and the temperature was already around -5F iirc, perhaps colder. We knew it would be a cold night so we boiled water for our nalgene's. I went to bed continuing to wear all my clothes from hiking + my down jacket (base layers, FA Hangfire hoodie, hiking pants, rain pants, down booties).

About 2 hrs into sleeping I woke up *very* warm and proceeded to take everything off except my base layers. I fell asleep for what felt like a very long time (2 hrs?) until I woke up and noticed my feet were getting chilly and proceeded to put my down booties back on, this may have been because I couldn't place the nalgene near my femoral artery while sleeping on my side(?). A good time later I woke up again a little chilly, noticing my nalgene was no longer "warm"(body temperature I guess at this point?) and put on my FA Hangfire hoodie. The rest of the night I was very comfy.

I had the face hole opening pulled tight to just over enough room to have my mouth and nose sticking out for breathing. Loved breathing the brisk air!

When we woke up around 6am our thermometer read -18F, so I assume at some point in the night it had to be even colder? Either way, for 1558g of total weight (3.43lb) for the combination, to know we woke up at -18F and that I slept very well is quite comforting.

I don't know if I'd bother with a single bag at a lower rating for a few reasons: I don't know how often I'll be sleeping in these extreme temperatures, the cost of getting a 0 or -10 down bag is pricey, I'd rather spend the money on items that have dual use for this situation like down pants that I can also wear in camp. I can take both bag and quilt and know that if the temperature is not as low as I can always take the quilt off to prevent overheating.

I believe the swing in comfort from being very warm to slightly chilly was due to the temporary artificial warmth provided by the nalgene. I'd like to try again without starting with the nalgene and having only up to my mid-layers on to see how my temperature goes over the course of the night. How often I'll be sleeping at -20F though remains to be seen, and I can always have my stove set up to quickly boil water in the middle of the night if needed.