When you walk into a store from the cold, do you unzip your jacket to get warm? Sometimes I think that if I keep my jacket zipped up, I will keep the cold inside my jacket. Think about it.
When you want to keep something cold, you put it inside a bunch of insulation. Let’s say you are outside and it’s 60 degrees inside your jacket. When you go inside where it’s 70 degrees, are you keeping yourself colder by keeping your jacket zipped?