Last fall I added wooden framing to this steel hoop house frame and covered it with plastic, which has worked out very well except...
first, the photo from when it was finished last fall
I used foam pipe wraps to cover the tops of the hoops, thinking it would cushion the plastic and keep it from eroding against the steel -- unfortunately, the foam either reacted with the plastic or the black color of the foam just caused the plastic (which was just "regular" plastic, not UV protected) to deteriorate more quickly
I had hoped to get through this winter with the same plastic again, but will definitely have to recover it before the weather gets too cold!