I'm putting up a shed roof next to my shipping container, to have some covered workspace. Single sloping 4:12 pitch, going down from a conventionally framed wall on top of the shipping container. The other wall is roundwood posts and a roundwood wall plate; the 16' 2x8 rafters will extend past this wall about 30".
The local peanut gallery thinks that I should birdsmouth the rafters at the top, then just sit them on the roundwood wall plate and toenail them in place with structural screws. Failing that, they think I should cut a slightly notched flat on the slop of the rafters for each one, on the angle of the slope, and then toenail the rafters in with structural screws after dropping in to this slot.
I think the correct method looks pretty much like the picture below. I'm a bit tempted by the time savings implied by the suggested alternatives, it's been raining like mad here and I'd really like to be done sooner. Is my intended method overkill, for an unenclosed utility structure?
'Theoretically this level of creeping Orwellian dynamics should ramp up our awareness, but what happens instead is that each alert becomes less and less effective because we're incredibly stupid.' - Jerry Holkins
The best method is the one in your picture, For added security you might want to add Hurricane clips ( rafter ties).
If you need to get it done speedily then you can use the simple birds mouth with a corresponding flat on the round top plate, again added security with rafter ties is always recommended, especially in places with high winds.