It is not clear why you claim that per 1997 the diaphragm shall be considered
rigid. The definition of diaphragm rigidity has not changed from the 1994 to
As for the Building Official asking for a diaphragm rigidity calculation for
such a project I believe it is a little too far stretched. I wonder if they
require this for every building with a wood diaphragm.
Ben Yousefi, S.E.
San Jose, CA