You can check your snow load for the 2x6 rafters 24"o.c. to see if they will work or not, remember to add the drywall now on the rake to your dead/live loads. Won't work for the 4x's you want though, check around as said.
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17,000 dryer fires a year, when did you last clean the inside of the dryer near motor or the exhaust ducting?
Great info Gary thanks. I did some load calculations based on the information I found and a 50# load (on the belt of 30-35 snow so just went high with 35 and 15dead).
I did some rethinking about what would make the most sense and rather than 4X's I think two 2X's on either side of a rafter is better. Connecting them in between. I could then cover them and make them look like one "beam".
This would be a more traditional method and easier in some ways.
Doing the math I would need 3 of these "beams" to properly support the load but may be able to cut that down by using something stronger than pine and just 1/2" through bolts. The weakness is in the connections, not in the tension of the boards. Also these calculations are based on no collar ties (or rafter ties depending on what you want to call them all that height) so I should have a pretty good factor of safety in these calculations.
Thanks for all the help so far! I will keep things posted as they move along.