Hi guys, I have seen all types of things used, but I was wanting to find out what type of materials most of you use for a door opening to go from one area to another that doesnt actually have a real door. I have seen black freezer vinyl strips, cloth, etc. and I was just wondering what worked best/didn't work well, and which were the most inexpensive and still fire retardant. If anyone has any ideas or websites to order from please let me know! Thanks!