What I have learned is that plank decking will have diaphragm value if used in the following fashion:
1. Place it diagonally (45 degrees).
2. Use plywood/sheathing over or under the decking. However, for aesthetics reasons, placing sheathing on top is better. Nailing of sheathing to the planks should follow the standard sheathing nailing pattern. We must provide blocking at perimeter to transfer shear from horizontal to vertical elements.
3. I quote the following from Lock-Deck publication:
“Lock-Deck laminated roof or floor decking in 3”, 4”, and 5” thicknesses may be designed to resist lateral forces when a 3/8” bead of 3M adhesive No. 5200 is applied on top of the tongue-and-groove joint between adjacent decking courses. Random applied decking may be used and the nailing schedule is the same as regular deck.”
I hope this helps anyone who may need in the future.
Regards,
Lutfi