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I'm no design engineer, so caveat emptor.The weight of the roof is carried by three linear supports: the ridge beam and the two walls. To figure the load on the beam you would add up the load it carries on each side, which is half the load of the roof between the span supports. For the lower roof it would be 5' x 60' times 60 lbs = 18,000 lbs. For the upper roof you have the same plus the weight of the overhang. If that is two feet then the load on the beam for the upper roof is 18,000 + 2*60*60 = 25,200 lbs. So the total weight on the beam would be 43,200 lbs.But you don't have a single ridge beam. You have five separate beams that have junctions over a post. So for load calculations and beam sizing you want to know what the dimensions of that 13.5' beam need to be. That assumes of course that you have more rafters than bents. As presently depicted you don't need a beam. The beam would only be needed to support additional rafters. The reason to do that is so that you can use timbers of a practical size rather than having each bent rafter be oversized.For a ridge beam spanning two bents the load would be based on the 12' spacing, so (5+5+2) * 12 * 60 = 8,640 lbs. Note that equals one fifth of the total load.Each wall supports half the 10' span plus the load of the eave overhang. The total load for a wall is 7' * 60' * 60 lbs/sf = 25,200 lbs. Each 12' plate supports 5,040 lbs.The load on the posts is done the same way. Loads on beams are shared equally by the posts, so it is just a matter of adding up all the loads. For an interior post supporting the ridge, the load on each post is equal to half of each span it supports, which totals 8,640 lbs. For the outside ridge posts the load is just half that, or 4,320 lbs. That is just roof load and doesn't include the dead load of the wall.For the wall posts, each interior post supports 5,040 lbs. The corner posts support half that, or 2,520 lbs.

D'oh. Alaska! My bad. JT

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