To add one more test related to the subject.
Outside temperature naked: 37oC
Inside Heat Resistance building with 100% shelter buff: 30 oC
Inside Heat Resistance building with 80% shelter buff: 31 oC (near a window)
Inside Heat Resistance building with 60% shelter buff: 34 oC (near a door)
Outside Heat Resistance building with 20% shelter buff: 36 oC (near the wall but outside)