You will need the snow load and wind load requirement for your
area to even begin the calculations. The dead load is minimal at
10 PSF. You will also need to meet sheer wall requirements
especially if you are in a seismic zone. The depth of headers
will probably not be that bad to meet minimums. I really hate to
see garage headers, in particular, that sag over time. It is so
common on double doors. Set your design standards above the
I would look into using a continuous LVL (can be doubled in situ)
or other man made to avoid multiple headers and trimmers. You
might be able to clear span if the weight doesn't get
unmanageable. The separations between the doors could perhaps be
done with Simpson Strong wall portal system:
or the steel strong wall for sheer and load:
Keep the whole world singing . . . .
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