I got an original side door from 1922. Needless to say it's all warped and dented around the sides. My best attempts to weatherize have failed. It's extremely drafty. Various weather strips have not worked and the storm door helps very marginally. I was about to give up and just plastic wrap it leaving it unable for the winter, but I have one last idea however I'm not sure just how effective it will be. My idea would be to hang a heavy curtain over the door. From side wall to side wall. My question is kind of a general how to curtains actually provide insulation if they aren't air tight. The sides obviously aren't anywhere near tight with curtains so won't the cold air make it's way in eventually? Also what happens when I draw the curtain. Won't all that trapped air be released anyway?