gauvins

The prevalent clothing system logic is base + mid + shell layers, supplemented by wind shirt and puffy if we expect colder temperatures. The conversation on sleeping systems is more muted (usually limited to temperature ratings and synth/down). So...:

I am transitioning to a tarp+bug_bivy system and exploring sleeping alternatives. I envision a liner (base layer), probably a fleece; a mid layer (perhaps my current 40F down bag, perhaps a lighter quilt); and an overbag (shell) perhaps similar to the liner, perhaps just a DWR shell (ex: Argon 67) to protect the mid layer from the unavoidable misting caused by heavy rain on a smallish tarp. My current thinking is that I'll make two bags -- one out of Hard Face Thermal Pro that will be used as standalone bag on warm nights and as an overbag when if rains + an Alpha Direct 90gsm used as a liner when the temperature drops to close to freezing.

I want a system that can get me through freezing temperatures (I don't expect < 30F) and preferably something where the base layer would be sufficient when temperature drops to, say, 60F (15C). Minimal packed size and convenience/flexibility are what I am looking for. (convenience -- I currently leave an S2S reactor liner in the bivy, burrito rolled inside a 4mm evazote mat -- I can unfurl the system and be all set in about 2 minutes. Works for warm nights. A warmer liner would probably be enough for longer portions of a tour.)

Still early in the process, so I'll appreciate any comment/suggestion.

imi

I sleep under the stars unless it’s raining heavily or there are lots of bugs. My layered sleep system is old school and animal product free. Heavy and bulky but it’s worth it for me.

In summer I sleep on my tent’s footprint, no sleeping pad, on top of a synthetic 3 season sleeping bag in an inner bag sewn from a cotton sheet. I put mosquito repellant on my face if some of the enemy are sneaking about.

Below freezing I’m in the tent with a closed-cell thermorest pad. Same inner bag and sleeping bag, but with a second sleeping bag over the first. This second bag is the cheapest, thinnest rectangular kind (costs about $10), but the heat difference it makes is incredible.
If necessary I’ll wear a base layer and a buff or a beanie.

I’ll only bring the sleeping pad, second sleeping bag and base layer clothing if I’m expecting low temps of around 7 centigrade and below.

My tent’s footprint is actually two of them sewn together with an opening to get into when it rains. i’ve slept through pretty heavy storms in this homemade bivy.

elcruxio

The discussion is not so much muted as it is usually unnecessary for your average camper. If we assume the very common premise that one uses a tent for shelter, considering anything beyond the sleeping bag is just moot. The tent keeps wind and rain out so no need to consider shell layers inside the tent.

Base layers and what to wear/have inside the sleeping bag is pretty highly discussed though. Some swear by liners while others love their merino base layers. You can of course combine both. I like wool socks.

For more hardcore folks who bivouac (eg. military), the whole discussion about shell layers and modular sleep systems is much more relevant. However while a military grade modular sleeping bag able to handle anything from summer breeze to truly arctic is very versatile indeed, the weight is typically enough to make even the most kitchen sinkesque tourist blanch.

While a bivy is light as shelter, it isn't ideal with a down bag since bivys lack ventilation. A moistened bivy and a subsequently moistened down bag spells a bad time if it's cold out. So the offset of bivy in difficult conditions is a synth bag, which is inevitably heavier + more bulky. It does come down to which compromises one wants to make.

I feel it needs to be said that there's only so much you can do to increase a bags temp rating outside of literally double or triple bagging (which what the military folks do with their modular bags).

timdow

There is a canned solution:
https://www.bigagnes.com/collections...er-3n1-series/
At 2Lbs 13oz The setup above is fairly low weight.

Tourist in MSN

Thanks for posting, I was unaware that anyone was doing something like that. I am not interested enough to buy it but I like to know what is out there.

gauvins

Interesting but overkill in my case. A 30F comfort would be enough.

My current system (an S2S reactor + Zpacks 40F bag) packs to 5L, weighs < 800g and is good to high 30Fs. Replacing the reactor (close to 400g) by an Alpha direct liner (200g) and a Thermal Pro shell (350g) would probably lower the comfort rating close to 20F and allow for interesting mixes and matches (i.e. shell only good to 60F, shell + liner good to 50F, etc.). I expect the liner to pack smaller than the reactor, whereas the shell might be a tad bigger, but that wouldn't be a problem since I lash the bivy + pad + liner burrito style on the side of my rear rack.

Will update

Paul_P

A sleeping bag can be too warm during a summer night, but the liner by itself just right. So I see layered sleeping as very useful, going from just a t-shirt and boxers on the mat, to that inside just the liner, to long-sleeve t-shirt and longjohns, to all that in the sleeping bag. Socks or a tuque by themselves always make quite a difference at any level.