I'm enlarging an opening for a front door. I'm trying to work out the header size. Please see attached picture for reference.
Structure: As the structure of my house doesn't match what is in the code as reference points, I'm taking what I would consider the next "highest" structure (Roof, ceiling and one clear-span floor)
Ground snow Load: For my area the snow load is depicted as 55 psf. So I have rounded that up to the 70 psf column.
Building width: As shown/mentioned in the picture, the house is 20' wide. There is a little more to this however. It's a 100+ old home. It's almost as if they built two sections together but with one roof. So the one section is 20' wide by 17' deep and the other section is 20' wide by 30' deep. (the picture only shows the 20x17 section). The 20x30 section has the roof running perpendicular to the 20x17 roof. Given this, I've selected the 24' Building width.
Span: The span of the new opening is 6'. With this in mind I have two options in the 70 psf, 24' building width column: 6'7" or 6'5".
Header size: based on 6'7" I should use 3 2x12s or based on 6'5" I should use 4 2x10s.
So the question is, Am I really reading/understanding this correctly? 3 2x12s 'feels' like overkill for a 6' span.
(Just a side note, currently there is no header over the 3' opening!)
I've attached the table section of the ICC IRC 2021 code for reference.