Drywall Soffit Calculations

[rgerk]

I have a client who wants some calculations for a drywall soffit. The soffit will hang from a metal deck roof and span approximately 30ft over some shelving. My first thought is just put it up. It seems as if the drywall will act like a deep beam against the studs and make the span, but I'm unsure of how to calculate this. Any ideas on drywall properties?

Thanks, Ryan

 

[UcfSE]

Does it hang vertically or horizontally? I would not rely on the drywall strength for anything, and I have not done so in the several ceilings and soffits for which I have done engineering. Use light gauge framing and hang it from the roof members. I never attach any hanger wires to metal deck, always to joists, beams or slabs or the like.