Help Needed - Garage Door Header

[lcifers]

I'm helping a friend frame a garage and have a question. One wall (a wall bearing the trusses) has 3 garage doors in it. Two are 10' wide and one is 12' wide. Can someone tell me what header size to use or a resource for finding out? I have a feeling that we will have to use an engineered member, as I dont think a pair of 2X12s will do the trick. But I would appreciate some guidance.

The building is 36' deep, with 1' overhang, so half a truss is 19'. The roof pitch is 10/12.

Thanks in advance,

- Luther

[DanG]

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 minimal L/360.

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: