Properties by Means of the Guarded-Hot-Plate Apparatus. 1.4 Design/Performance Requirements. A. Structural Performance: a. Deck: Uniform Load – An allowable span of 16 in. on-center and 100 lbf/sq.ft. b. Tread of Stairs: Concentrated Load: An allowable span of 12 in. on-center, and 750 lbf...