1. Let's use Francis' numbers 25 psf, no reductions, seismic C, 90mph. Feel free to use other numbers.
2. 10 psf will cover DL, no don't pick up any diaphragm action here just load it
3. Let's use #2 SPF, snow, repetitive member
4. 2x12, for insulation, keep it simple 2' oc spacing. How did I arrive at those sizes, typical,... academic exercise, pulled out of air feel free to use something other. Different depth plumb cuts are ok, ridge must simply be deeper than the deepest rafter to support bottom edge of plumb cut. If that offends drop the dormer rafter a size,we'll insulate the level ceiling there, it'll still check on this building.
5. Not allowed, Footnote Table R802.5.1, Why, the tie tension and bending moment get out of hand if they are restraining the rafter thrust from high on the rafter. Is that the situation here, no.
6. top of fl deck, anything, put the ridge at 35'. You have width and pitches, sufficient info for general plate and ridge heights, I used 12/12 and 24' wide, 3/12 to make it easy on you. I sketched quickly, go grand call both overhangs 2'.
7. I was tempted to say sheathed with a tarp. What I'm asking for is that no diaphragm action be used in your analysis of the dormer roof. 50' long, call this the entire roof. IIRC the engineered dormer in the photo I posted was about 24' long, ridgeboard. The framing under the ridge is temporay construction support, it was removed. I stated that the shed roof diaphragm was probably sufficient to take care of lateral loads but upon thinking more I don't believe we even need to bring that into the equation, I'm calling it gravy for the purposes of this discussion, don't use it.
8. There was no center wall in the original photo of that engineered shed dormer. For what its worth that build was the subject of a feature article in a trade mag. The article was on design rather than structure. However over 350 home companies were advertising in that magazine at that time. I know many of their design depts read those articles. Not one wrote in commenting that they were concerned with the design. Having built basically the same detail for a number of them over the years, neither am I. Walls conventionally framed 2x6- 16 oc fully sheathed.
9. Your baby, the moment I break out my calculator here it's going to get off track but I do have a fair idea, let's see what you come up with. I've been showing what has worked and been standard among many thousands of homes. Go back to the beginning, I didn't really disagree with you did I? Show your calcs.
10. Why do you think the connections are anything higher than the heeljoint table would cover? If this were a 3/12-3/12 would the tension be higher or lower? Now look at the heeljoint table, it's using 16 commons, we'll be shooting .131's. Make the conversion, I can do it from a referenced table. You can go round the horn and use the yield limit equations if you want to do it the hard way. Double check the heeljoint table, I'm not factoring diaphragm action, now check the table again, it's light isn't it? "Rule of thumb"... pull the trigger at least half again.
11. Vertical deflection of rafter over a wall is zero. Horizontal deflection of the wall does occur, I was wondering who would make it that far. For the loads above it is within acceptable limits though isn't it. Then we do have the shed roof diaphragm in the "real world".
Actually scooting around a plan with these drawing programs give me headaches, I learned with slide rule, pencil and parallel bar. I'm perfectly capable of drawing a phantom clevis with paper and pencil
. No interpolations from different conditions has occured here, standard practice. I've simply asked for you to show proof.
12. Third time's a charm, I've got others depending on my income. Y'all take care.