I normally commute anywhere from 0 to 35F this time of the year. My commute is about 7 miles one way. I usually wear one pair of cotton socks, my shimano road cycling shoes adn an old pair of cotton socks over the shoes. I have yet to get annoyingly cold on any of my rides. I think the main key is keeping the circulation going. I've tried layering inside my shoes, even buying bigger shoes, and I just can't get past the constriction.