plastic bags for VB

been using them for years and they work great.
I've been going with very thin poly-pro liner socks, bag, and my regular Smartwool hikers. In winter climbing leathers have been very happy standing around at -31C air temps.

Would go with the bread bag – less material and slightly more durable, but eh not like your going to stress when it comes time to replace them!

so you don't put the VB right next to your skin? Is that to avoid "pruning"?

Tim,
Vapor Barriers are expensive plastic bags. During the day, I wear my VB socks next to skin with a sock overtop. But, I wear a thin base layer under my VB liner when I go to bed…for comfort. All it means is that whatever is between your skin and your VB is susceptible to moisture from your body – but it still works…if I had VB clothing, I would wear my baselayer overtop…but I don't…so I make do! :)

I've always been advised to use the liner socks and have been very happy with them. No reason to change for me but see what works for you.
FYI, no reason to get an expensive liner in fact the thinner and quicker drying the better – I use the five doller poly-pro liner socks from MEC. Been very happy with the setup for cold days on the ice.

Thanks for your comments. I think I will try it with and without and see how it goes. While they don't weigh much, liner socks are something I don't normally carry. It would be one more thing to pack in a system that seems to be getting more and more complicated as I plan it. I might post my clothing and look for some suggestions as I have no experience backpacking in temps lower than 20*F.

Tim

I second what Robert and Stephen said, and I always have a couple of bread sacks in case I or someone else needs them. If you really want to get into it check out the articles by Will Rietveld, "Lightweight Footwear Systems for Winter Travel", parts 1,2,&3. Just click "Magazine" above and then Techniques; you'll find them there.

Plastic bags for VB's work great!

I'll use VB's in combo with a ski touring set up. I don't use VB foot systems often, but when I do, here's how I do it.

I use the really super thin plastic bags that come off the roller from the produce isle at the grocery store. They eventually break, but you can usually get two days out of one bag.

NO LINER SOCK, the bag goes right on my bare feet.

Then a medium thickness wool (or wool blend) sock.

I do this to keep my ski boot liners dry, no other reason. But, when I stop hiking, my feet cool off fast, so I need to change out of the plastic bags and into a regular sock system. If not, I get cold feet.

I like keeping the liners dry, it's a big plus on a long trip. They don't freeze at night.

Would there be any benefit to foot -> bag -> medium sock -> second bag -> shoe?

Maybe that would prevent heat loss when stopped?

> Would there be any benefit to foot -> bag -> medium sock -> second bag -> shoe?

To some degree. It's a bit like using a VBL inside a shoe with a WP/B membrane. The outer layer, either bag or shoe, stops the sock from getting wet, IF the snow is at such a temperature that it could melt on your shoe. However, if it is that warm then maybe you don't need the inner VBL anyhow. A delicate balance.

Cheers