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 Fiber Lok is thick and dried out looking, Can it still be used? Are your Epoxies recommended for outdoor use? How do i figure out how much Silicone Rubber to buy? Comments 0 comments Article is closed for comments.