I have worked outside in Canadian winters since 1977.
It goes like this up here for me:-The first layer should be of a formfitting design and made of fabrics that breathe and keep you dry.
Polypropylene or knitted silk are popular choices. Cotton is definitely not recommended.-The second layer serves to keep you warm. Polar fleece or genuine pile wool (like Grandpa’s old sweater) are recommended.
(a workmans vest was always the most important component to ward off the cold,your body will always extract heat from other areas [i.e.hands/feet/head] to keep your heart warm first,so keep that chest insulated!)-The third or outer layer should offer protection from wind, snow and rain.
Wind-resistant and water-repellent materials, like Gore-tex, are best suited for this purpose.
Of course,also protect your extremeties,again with synthetics/genuine wool and remember to wear a cap,toque or headband to keep the 40% heat loss from your head and neck areas controlled.Edited by 5aces - 10/16/11 at 10:29am