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Porch Beam Size Help

Branden Battig

Registered User
Joined
Jun 11, 2020
Messages
5
Location
Peninsula Oh
I am building a garage 28' (Gable End) x 32' (depth) with a 10' overhang porch. I originally sized the porch to have 2x8 rafters (24" OC) attached 2-2x10 beams attached to 6x6 posts @8' OC.

I did not like the layout of the 8' OC and want to change to 10'8" span on the beams. I am having trouble calculating the beam size. I am in NE Ohio so I am using a 20psf snow load and 15psf dead load. I plan on finishing the underside of the porch with additional rafters and barn siding.

My burning question is the double 2x10 beam enough to span the 10'8" OC posts on the porch?
 
Can you please clarify what the tributary length of the rafters landing on the beam is?

Sounds like the rafters span 10-ft from the exterior wall to the beam, which would be 5-ft of tributary. Add in a foot for an eave, by my guess you have 6-ft of tributary acting on the beam.

This is what my calculation looks like then.
upload_2020-6-26_12-24-58.png
 
"Sounds like the rafters span 10-ft from the exterior wall to the beam, which would be 5-ft of tributary. Add in a foot for an eave, by my guess you have 6-ft of tributary acting on the beam." ~ CORRECT. 10-FT RAFTER SPAN WITH 1' EVE.

Is your 1st post saying a 2ply 2x10 (hem-fir) will work? What about a No. 1 Southern Yellow Pine?

I downloaded a trial of the sizer app, looks awesome, just a lot to learn. Thanks for your help.

 
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