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Strict Deflection Constraints w/ Heavy Snow Loading

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SHEAR_FORCE

Structural
Sep 2, 2022
12
We are designing a two-story moment frame in a new home with the upper bay housing a Marvin Windows Ultimate patio door, with windows above. The 28' wide moment frame is supporting large roof snow loads of ~4200plf. It looks like all of the Marvin ultimate doors require an 1/8" max deflection. We currently have a truss designed over the door to meet this deflection requirement. Is there a way to meet these deflection requirements with a non-loaded secondary header within the frame below the frame top chord? Attached is an image of the frame.

Thank you for your help and opinions!
Screenshot_2024-03-15_080321_ewwxto.png
 
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Is there a need to use a portal frame? Can you use the floors and roof as a diaphragm? and the end walls as shear walls? and maybe preengineered wood trusses?

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Thank you for these options! We have already pursued them. The diaphragms and shearwalls don't meet aspect ratios.
 
Can some sort of slip connection be provided to the beam by Marvin? 28' Seems too far for a steel stud header, or at least a reasonable one.

I'm not quite sure why the roof has structural steel. My first thought would be to have pre-eng roof trusses (or LVL' if too shallow) coming down to bear on the W10x77. Then tie in the roof diaphram to the moment frame with bracing or clips for lateral. You could also move the beam up into the truss cavity, have the supplier provide hangers or design for top chord bearing, and then provide an HSS girt above the window, which would only take its self weight and maybe some wall weight. If you wanted to add sag rods that could work as well, just have to make sure they don't transfer any load to the girt, so some sort of slip connection.
 
We are eliminating the top chord and it will likely be a smaller frame with a secondary hss or wide flange header below the top chord. I would assume that the slip connection would only need to be on the siding. We can design the secondary header for wind loading as well.
 
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