I've had an old storm door stored in my garage for at least five years now with the intention of building a cold frame. Well, I think it is finally time. I have the door, and thanks to a deck removal, a large supply of scrap wood. The benefit of a cold frame is that you can get a jump on the growing season. I know, I have a heated greenhouse but there is never enough space! A cold frame also has the benefit of being a passive system that shouldn't cost anything to operate!