simple shed with no walls
I'm working to create an aluminum roof shed with no walls. The shed has 4x6 post in the ground that are buried 4 ft deep and 8 ft out of the ground. I'm using 2x6x20 to frame out the top support to allow for 2x4x10 rafters.
My question is with using 2x6 for a center support beam for an a framed style roof, will the span of 18 ft and using 2x6x20 be strong enough to support the roof?
I've been thinking that it may be best to add another 4x6x12 and nail into concrete using the hurricane bracket.
(the 4x6x12) would replace the 4x6x30" which is displayed center screen in the attached picture.)
Looking forward to feedback.