Thanks for your insight, Freddie. I hadn't realised that building regulations varied throughout the country.
The building regulations are a national specification & they dont vary throughout the country (except Scotland). As with all specifications, what varies is their interpretation & the understanding of local BC officers, some of whom seem to be incompetent idiots. If you have a good understanding of the regs, never be afraid to challenge local interpretation; at least it will make the officer go away & check it properly.