Originally Posted by MichaelW

The Everest/South Pole type of conditions are not very applicable, being very cold and dry. Under these conditions you dont need waterproofing, just very effective windproofing. The humidity gradient results in optimium breathbility of gortex compared to more humid climates but there are other materials that work more effectively.

The classic Ventile mountaineering smock is still used by the British Antarctic Survey.

Tests on vintage mountaineering kit show that under Everest conditions it performs very well indeed.