Converting house into 2 flats?? resistance to the passage of sound

Property Investment

I am in the process of converting a house into two flats (ground and first). The planning was fairly straight forward but the building regulations relating to Part E - the resistance to the passage of sound are not!! Although there are diagrams i feel there is some confusion. I am a builder but I have found it impossible to find local information and advice. (Wolverhampton) My architect seems to know little, who originally drew up the plans and I wonder if there is anyone who has successfully passed this test who can offer a few tipsa