Alittle help on understanding the layering system of hiking clothing.

[Different Socks]

With all the improvements in clothing over the last 20 years, There are some things I just don't understand when it comes to layering your clothing. To me it seems that some things are redundant, while others can be crucial.

So based on different weather and temp scenarios and the time of year, please explain for me the layering system for using the clothing below:

--down jacket
--fleece pullover
--hard shell
--soft shell
--long under wear
--rain pants/jacket
--various shirts made from multiple materials
--base layer

I know some of these things are obvious, but what was easy to figure out 20 years ago, is now very confusing.

Thank you.

[Meriadoc]

I will take a stab at crafting a simple answer.

(1a) Warm weather, dry
Base layer for hiking.

(1b) Warm weather, raining
Get wet from rain: Base layer for hiking.
Get wet from sweat: Base layer and hard shell for hiking.

(2a) Cooler weather, dry
Base layer and shirt

(2b) Cooler weather, raining
Get wet from rain: Base layer, and wind proof jacket
Get wet from sweat: Base layer and hard shell

(3a) Yet cooler weather, dry
Base layer, shirt, and soft shell/fleece

(3b) Yet cooler weather, wet
Get wet from rain: Base layer, shirt, and soft shell/fleece
Get wet from sweat: Base layer, shirt, and hard shell

Rain pants are added in when it is cold and windy.
Long underwear is used for sleeping
In non-extreme cold, down is used only when not moving, otherwise the sweat generated will wet it and reduce its insulation.

In extreme cold, use vapor barriers to keep the body warmer and to keep insulation dry. In this case, a down jacket while moving would be okay as long as it doesn't cause sweating.

[juma]

But, bottom line, it's too much clothes.

[Another Kevin]

Merry the Hobbit is right... and I don't think I ever carry all the stuff you list (what I carry varies by season). On my last trip (moderate winter, not extreme cold) I had:

Baselayer + dry baselayer for sleeping
Fleece jacket and pants
Convertible hiking pants
Down puffy
Frogg Toggs rain suit
Wool socks (2 pair) and polyester sock liners (2 pair) and bread bags (2 per foot, 1 spare pair per day, go over the sock liners as a vapor barrier)
Mittens and glove liners
Balaclava and beanie

I think the layering system there is pretty clear. It was chilly, so while on the move I wound up wearing baselayer, fleece jacket, hiking pants, glove liners and beanie (plus the rain jacket, and switched from glove liners to mittens without the liners, when it started to snow). If the temps had got up around freezing and the winds had been lower, I might have peeled down to baselayer and hiking shorts. If the winds had been even higher, I'd have needed the rain pants. Hanging around camp while cooking and eating supper, I was wearing every stitch of clothing I brought (except for the baselayer and socks I slept in). If that wasn't enough, I could have stayed warm in camp by wearing my sleeping bag as a cloak.

I was only cold briefly when changing clothes in evening and morning. (Naked in a tent when it's 18 *F inside the tent is cold.) I'm most comfortable in a sleeping bag in cold weather wearing baselayer, sock liners, glove liners and balaclava. More clothing in the bag is less effective than spreading any extra clothing on top of the bag. I decided to splurge and warm the bag with a chemical body warmer. When that got too warm, I took it out and wrapped my hiking socks, glove liners and beanie around it so that they were dry and toasty in the morning. The midweight baselayer that I hiked in dried out in my tent by morning, but was anything but toasty. And of course my boots were frozen. I've never found a good answer to frozen boots.

Winter hiking is all about moisture management. If you're not cold when you start walking, you'll be wet when you stop. So wear one less level of insulation than you think you need. It's only mildly unpleasant to hike for 20 minutes and decide you need more clothing. It can ruin your whole trip if you sweat out your insulation.