Done to death I know I’ve got mine out at the moment as I’m taking the roof off to do another couple of jobs and they are a mess. Not just sagging vinyl, but the actual backing of the liner is soft with no rigidity in it. I think it’s been soaked at some point and it’s broken down the compressed material it’s made from. I’m wondering if I can get it flattened out on a surface if there is a hardening gel or resin I can paint on to give it some rigidity back ?? I considered fibreglass as well, but it needs to have some form of flexibility to get it back in. Any ideas anyone ???