liz wrote:
Is there an official minimum size a room must be before it can be
described as a bedroom?

Is there a minimum size according to building regulations?

Dunno. A couple of months ago I rang an estate agent to complain about
their describing a room as a bedroom, when it couldn't take a standard
sized single bed. He was a bit miffed, and said that of course it was
possible to get a bed in there. Would've been a small one, & a tight
fit, too (ooh-err!).