Garden room roof insulation detail

This although, I say its the last time i explain, probably wont be! Warm roof/ cold roof, hybrid, compromise. I know this will have the roofing guys screaming at the monitor, its how it has to be! 2.5mtr is height limit and we are down to the bare bones on every detail to give maximum timber sizes and still maintain head height and over all height. Any way, this works, like it or hate it, its what we do, thanks as always!!1