Question: what is a 1 hour rated wall?
Answer: According to the book "Commercial Drafting and Detailing," a typical one-hour fire rated wall consists of 2x4 studs spaced 16 inches from the center of one stud to the center of the next, covered by 5/8-inch, type X gypsum board. Type X gypsum board is wallboard to which non-combustible fibers have been added.