The site didn't require a lot of work as far as leveling. So we tilled it up to loosen it so we could move it around. Then we leveled it and spread the 19 tons of gravel and compacted it. Ended up with at least 4" of gravel all around. I asked the concrete company and they said no rebar was necessary unless I was going to get heavy equipment on the edge of the slab. His comment was something like "It won't need rebar unless you are working on heavy equipment and driving it off the edge.
I used 4k psi with fiber and the concrete finisher said it was overkill, that I could park the loaded concrete truck on it when it was cured. He was almost amused that I used that. He said 3.5k would have been more than enough. But it was only like $9.50 a yard more so I feel like it was money I could afford to spend. So between the two I felt fine with the way I went.
The finisher felt like the site prep was quite good and that it would be very stable. Of course we have no frost heave here and it is nice stable ground. Of course, someone with more experience or preferences might do things differently, time will tell if my advice was sound.
You are probably right on the 4' front overhang, it would have been nice to have. I didn't think of that. The stubby 2x6's are notched to lie on top of the 2x6 truss rafter. They are nailed from the backside through the rafter. They are also nailed to the purlin which they lie next to. It's not as strong as what you mention, but it's only a 10" overhang.
The truss is spliced with the 2x6 that runs vertical and with the plywood gussets which are indeed nailed and glued. The plans called for the truss to be built that way without the plywood gussets. Like I mentioned earlier, if I was to do it again, I would buy trusses as it would have caused less problems with the building inspectors. That being said, I have no reservations with the design. A local engineering firm agreed that the trusses on 8' centers would have been fine, but it was cheaper to buy the materials and add 5 trusses to appease the inspector. I figured if I was going to spend the money, I would rather have the extra structure though it wasn't needed.
