Vapor Barrier in Boots

I was talking to a friend about keeping warm feet in single boots, especially over a multiday trip. He swears by using bread bags over sock liners and under a wool sock to keep the socks and boots dry and insulating well. Does this work well and is it worth the trade offs? Pretty new to ice climbing and mountaineering in the Northeast so any tips are helpful.

It will definitely reduce the amount of moisture that builds up in the boot over the course of days. Some people can tolerate the dampness that is inevitable inside the VBL, others find it too much. Bread bags are cheap; give it a try.

Try it. It works for ​some people​​​ so your buddy isn't totally talking out of his ass. I found diminishing returns from adding multiple layers of socks, made boots too tight. Maybe I have fat feet.

Another trick is a couple of 500cc Nalgenes of boiling water slipped into your boots at night, same shenanigans as drying out a sleeping bag.

Double boots are really nice when you're spending multiple nights outdoors. 

I do this regularly if I'm spending more than just a night or two out in winter. But I use thin plastic shopping bags instead, sometimes doubling them up. The liner sock gets pretty sweaty but it dries very quickly in my sleeping bag at night and my boots stay totally dry inside.

If you’re doing a couple multi day trips renting doubles is an idea. So nice to pull just the liners out and stick them in your sleeping bag overnight instead of an entire single boot.

I've had good luck with 3mm neoprene booties.

It works, especially if your feet sweat a lot.  I use the same setup as your friend, but in snowboard boots.  I wear Icebreaker "MEN'S SNOW LINER OVER THE CALF", then a thin kitchen garbage bag, followed by either normal or Lenz Heated Socks.  I have very cold feet all the time.  The vapour barrier makes a big difference during long riding days.

AlpineIce wrote: Rab makes VB specific socks.

Review here.

I've tried them on.  They're too short for most snowboard and ski boots.  The cord-lock sits below the boot cuff making them uncomfortable.  A kitchen garbage bag works just as well and cost pennies.

thanks for the input. Ill definitely be experimenting with VB socks this winter! I'll let you know how it goes