How long does it take for Fiber Lok rug backing to dry? Monica P. March 03, 2020 14:40 If used in a dry, warm environment around 2 hours. If used in a a cold or damp environment around 24 hours. Related articles Can I wash and dry my rug after applying Fiber Lok rug backing? Fiber Lok is thick and dried out looking, Can it still be used? Comments 0 comments Article is closed for comments.