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I can help. Can I get back to you in a couple hours?
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If you have those struts, I would assume that wall supports the roof. I can size the beam for you if you can give me the following information.
The length of the joists on each side of the beam.
The city and state so I can look at snow loading.
I can size the beam, but you will need a detail to provide lateral stability to the beam since the top will not be braced by joists or sheathing.
If the struts are restraining movement then they are taking load. If they are not taking load then they wouldn't be helping with deflection.
I apologize. I completely missed the dimensions you provided. I will size the beam and post the size in the next hour.
You will need a 7" x 11.25" 2.0E LVL to work for strength and limit deflection to L/360.
It's not just section modulus, that's for strength. LVL are almost always controlled by deflection.
I used 30 Psf live load (3/4 of the attic and roof combined) and 25 psf dead load (10 for attic and 15 for roof). The required moment f inertia for L/360 deflection is 813. The actual moment of inertia is 830, so it's pretty lean for that deflection ratio.
Hello. Do you have any other questions for me on this topic? If you could rate my answer, I would appreciate it.