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Wood structure with wood diaprhagm - question on disconntinuity

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I have a condition that I could use some opinions on. I have two diaprhagms - 
one is low pitched 2:12 while the other is relatively flat. They meet in the 
middle of the residence and there is a change in elevation of about two feet. 
The lower flat roof flush frames to a series of posts and beams and the upper 
roof frames on a poney wall above the beam. 
The analysis indicates that there is sufficient shear at each end to transfer 
shear into resisting walls at the ends. There are no interior shearwalls to 
use since the roofs join on beams and posts.

In the old flexible diaprhagm design I would generally consider the beams to 
be a hinge in the diaprhagm and design some or all of the columns to be 
laterally restrained. However, in the new methods the roof should be 
considered monolithic in nature and capable of distributing shear to the 
extreme edges.
If I use the columns as I would in the past, I must penalize the structure by 
using an R of 2.2.

I don't have a problem doing this other than to justify the cost difference 
to the owners for my decision.

I would like some opinons as to how others have resolved similar situations. 
Do you consider the line of beams to be hinged or do you consider the 
diaprhagm capable of distributing shear to the edges of the enveloped roof?

The loaded questions, If you do consider the beams to be a hinge in the 
dipaphragm, how can a torsional analysis be considered valid if th two roofs 
are simply supported beams rather than a continuous beam?

DEnnis Wish PE