Favorite layering system for legs when ice climbing?

Reigniting the stoke for ice and wanting to dial in my systems the best as possible. Currently I wear various thickness thermal bottoms with some old medium weight REI fleece pants then a thin soft shell or hardshell pant.

What are you favorite fleece type pants layers. I was reading about Patagonia Nano Air pants but seems like they are no longer in production. Try the R2 tech fleece pants? Open to suggestions! 

Also, have a favorite pair of midweight socks for ice boots? Any company using better tech? I just picked up several Darn Tough models to try out various thickness. 

Thanks in advance! 

Well, Nano Air pants (sorry dude), under the galvanized bib. If cold, I layer the Capilene Air, or if warm, that same layer with no nano.

I'm suprised you're able to do thermal bottoms, fleece pants and a soft/hard shell. I've never once worn 3 full layers for bottoms ice climbing, but of course YMMV. Spring ice, just soft shells. Winter ice, soft shells (non membrane) over varying weight thermal bottoms most commonly around Cap 2-ish in weight, but sometimes R1 weight or Polartec Powerstretch fleece (I find the latter two to be about equivalent in breathability and warmth for bottoms and tops). Worked in the North East and Montana both of which tend to be cold. I think if I needed more leg layers than that for technical ice it's too cold for climbing to be fun. 

For socks I've had luck with Darn Tough and others of similar weight. I picked up some Lorpen Primaloft socks are quite impressively designed but I haven't found a cold enough day to use them yet. Seem like they would be great if you're close to the lower temp limit of a boot. 

Ben has his location listed the Canadian Rockies which is cold!

R1 pants (I had a tailor cut them down to knickers, they're cut like sweat pants)

MH high loft pants (warmer)

You could also look at Polartec alpha direct leggins from Timmermade or Senchi. 

I don't think the Techface fabric is best used as a midlayer, it's got some wind/weather resistance and corresponding decrease in breathability. It's like halfway to a softshell. I had the R1 Tech jacket and I've not tried the R2 Tech pant in fairness. The classic R line is more ideal when used under a shell IMO.

Darn Tough are good. Sock choice is more about your particular feet and finding socks that leave room to wiggle your toes. Might be thin, might be thick. Depends on your foot, the boot, the insole. Those Lorpen ones are too tight for my feet in all my boots, but they sure seem toasty. I have the Lenz heated ones too, nice for climbing day trips and resort skiing.

Also can find military surplus grid fleece pants (exact same stuff as R1 material) which work pretty well. Cheaper than pata, no pockets, and come with a fly - found mine for 3$ at a thrift store, should be available online for a good price with some searching. 

What kinds of temps are we talking? I like: merino bottoms with shell pant of choice, soft or hard, depending on wind or wetness. Nothing more.

+1 Nano-Air Pants; they're fantastic.

For ice I use:
1/ Merino wool boxer (Ortovox or Icebreaker)
2/ Ortovox 185 Rock'n’wool short pants or Icebreaker 200 Oasis Legless
3/ La sportiva Softshell pants (important is to have vent zip and gaiters)

Beginning and end of the season I may also take a light hardshell pants (Haglofs LIM III) but it is very rare that I need it. 

For socks I go with a wool, midweight/mid-high option (Smartwool, Icebreaker or Teko)

Montbell makes the UL Thermawrap Pant, which is very close to the nano air pant. Pretty nice in single digit temps and below. 

Agree with Linnaeus, 3 layers seems a bit much.  Temps were in the low teens yesterday in NH and I wore Pata mid Cap base under my Arc Sigma AR (mid weight soft shell) and was fine. 

If it's a warmer day I'll use Nike running tights as my base as they slide better under the softshells. 

For socks I'm currently loving Smartwool Mountaineer socks (now called the athlete edition?!?) as they're not too thick and have great calf compression. 

We all run hot and cold differently. if I’m climbing and moving I wear less than if I’m instructing and not moving. Obviously it’s about the temps. With that I’m usually a 250 weight Smartwool on the legs below 25 and doubled with a 150 weight in single digits. I usually wear soft shell pants unless there’s a long approach I wear GTX with side zips for heat management.  

My legs themselves have never felt cold with just a thermal base layer and I wore that for years but my toes have been consistently happier since I started wearing a leg mid layer. YMMV, everyone has their own thermostat. 

Montana climber here, and though we arnt as cold as Canada I've been out down to -23f! As said above going out below 0f the ice climbing becomes less fun but it's doable. For context I always run a bit warmer than my partners. 

Unless I know I'm going to get soaked I always try to wear softshells so that I can dry off any sweat that builds during activity. I always wear an airblaster onesie (merino/poly mix) that I or call a light weight layer, then add layers based on temps.... Above 20f nothing but that and softshell or shell.... Below 20f a mid to light fleece or merino..... Below 5f UA base 3 (mid to heavy poly) fleece.... Also a pair of over pants, down or synthetic, is always in my pack for times I'm not being active or really cold days. 

For socks I love the smartwool mountaineering pro (designed by Conrad anker, literally my favorite sock though I think they may be discontinued) and then if it's below 15f I layer the classic smartwool mountaineering or merino33 mountaineering over it. 

I used this system for Denali and I felt plenty warm enough for all the conditions encountered being that last season there weren't too many storms before -20f during the spring season

for socks I like both smartwool and darn tough.  for me they seem to work equally well

I tend to run warm, so for legs I typically wear only a thin base layer (usually lightest weight lifa) and a lightweight softshell of schoeller dryskin or equivalent.  for near-0f, I will layer an expedition weight lifa or capilene between base & softshell.  for extreme cold (Denali) I've added sherpa-pile pants (good luck, I made mine myself), but this was decades ago, and were I to update that extreme cold layer, I might try polarguard alpha for a more packable alternative.  the sherpa pile pants were worn under a hard-shell bib (also home-made, I'm a cheap bastard), and would not fit under the soft-shell I currently wear, but I've never used them outside of Alaska or South America.

I like a 3/4 length merino base layer with knee high Darn Tough socks. Great set up for skiing too. Pair this with light softshell (Gamma LT) or mid weight softshell (OR Cirques).  

Patrick N wrote:

Also can find military surplus grid fleece pants (exact same stuff as R1 material) which work pretty well. Cheaper than pata, no pockets, and come with a fly - found mine for 3$ at a thrift store, should be available online for a good price with some searching. 

Upvoting Patrick here. He is 100% right. I bought these thinking they were just another cheap baselayer, but they are R1 material pants with a fly. Loose enough to be a midlayer, but tapered tight (in a good way) on the lower leg and ankle. $15 on ebay or sportsmansguide or other army surplus. "Gen3 Fleece longjohn."

I climb in VT/NH in 0+F and I've only worn 250wt merino tights and I have ~2 layer Paramo softshell pants that are heavier and slightly more insulated. In warmer temps I'll switch up to lighter tights and/or lighter pants. I am hot climbing in cold temps in these layers so, personally, I'd be hesitant to add a midlayer. I do get cold on the belays though and over pants are a pain when doing anything more than cragging. Experimenting with a zippered belay skirt :0 and it definitely keeps you warmer, but it's also finicky when you're tied in to the anchor and not on a larger ledge.

I run some Pata Cap leggings with some older Mix Master pants. Really warm, durable, and allow for good mobility. Unfortunately like all good things Patagonia makes, they discontinued the Mix Master line years ago. 

If it warms up or I'm doing something more mixy, then I go with some microgrid sweat pants and my Arcteryx Gamma Lt pants. If it is way warmer then I'll just go with some leggings and the Gammas and be fine.