Calculating Rigidity of a diaphram

[SeanStruck]

Hello (this is my first post )

I am designing a structure with a cantilevered diaphragm. The shear walls are CMU walls, and the roof is plywood over 4x T&G.

How do I go about checking to see if the roof diaphragm is rigid or semi-rigid?

Thanks

 

[sandman21]

ASCE 7-10 has a check for rigid s. flexible, section 12.3.1.3, the diaphragm is flexible when max diaphragm deflection is greater than 2 * the average drift of the vertical element. A semi-rigid analysis involves modeling the stiffness of the diaphragm.