Water vapor is far less likely to reach the dew point and condense at some point during its migration through foam, than it might be as it migrates through glass...

And IMO it is unwise to put a convection current (the ventilation) next to such a potentially volatile fuel supply as foam, as hot cinders my very well be drawn into a cold roof during a potentially beatable fire -

I typically sheath tight to foam and provide a secondary cold roof above it