Adding lean-to to pole barn

[hookdrvr]

I've started building my pole barn, its a kit consisting of metal trusses instead of wood. Its 40x60, 6x6 post, poured slab with metal roofing. I'm using bookshelf girts so I have less lumber involved when finishing the inside. The top band is a 2x6x12 that's screwed into notches in the 6x6 post, nothing else is attached to those 2x6's. I'm adding a lean-to on either side of the building and looking at the best/safest way of attaching the rafters.

My question is this, I want to attach 2x6 rafters for the lean-to to the band that is attached to each 6x6 on the building, but I'm thinking the load carrying capacity is not there. My current thought (based on limited construction knowledge) is to use 2x10x16's to overlap the 2x6 bands and being 2x10, these will go up to the outer 2x6 that sits in the inner pocket and prevents racking, on the steel trusses. The 2x10 will be outside of the post, but that's fine as I'll butt the exterior metal siding to the bottom edge of the 2x10. Will the 2x10x16 overlapping, glued and screwed, to the 2x6x12, and using timber screws through both boards into the 6x6, be enough to carry the load of 2x6 rafters 24" on center? My roof pitch will be 3/12 and the only roof load will be from rain, no freezing weather here in south Alabama.



I'm at work and this is the only picture I have. The 2x6's in question are in the top left corner of the picture.

 

[i579rbd]

I think if you swapped the outside 2 x 6 for a 2 x 10 you would be fine. You could also put a block between that and the inside 2 x6 and screw them together for extra strength. I am a chainsaw math kinda guy and not a engineer but all my buildings have withstood some pretty severe winds here in N Cackalacky.

 

[Xfaxman]

They used 2x12's on my shop, but we get some snow here.