2" Gypsum Plank

[pat2]

I am working on an existing building that is 60+ years in age. I need to check the capacity of 2" gypsum roof plank. Does anyone have any information about gypsum plank, or any idea of a name of an existing manufacturer I may call to inquire about the load capacity of the plank?

 

[theonlynamenottaken]

Are they the precast panels or the poured gyp-crete with half-embedded bulb-tees @ 24"-32" O.C.?

 

[pat2]

There are no embedded bulb tees. The panel widths are 12".