Ian_m wrote:
In an effort to make ignoring Part P easier (sorry re-wire kitchen) I have
removed the plasterboard ceiling which was 15mm plasterboard.

Should I just replace with plain 15mm or would moisture proof and/or sound
deadening (as my sons bedroom is directly above) be more suitable ? Any
thoughts ?


foil backed offers a bit more damp resistance..

Unless you go expensive, soundproofing is very hard to achieve.