garage insulation

Hi All West Midlands based and looking for someone to tell me if I’m going down the right path. Just finished putting up 8x2 joists for a new master bedroom above my garage and looking to install insulation. Am I on the right path with the below and should I be worried about significant heat...

Hi All I wondered if you could assist me please as I am in the middle of insulating the ceiling of an integral garage/utility room and making a bit of a hash of it! There is a bedroom above the garage which gets cold. I have put 100mm of PIR between the joists right up against the floor...