The Building Regulations (or 'regs') are very brief. The Approved Documents, on the other hand, suggest (in considerably more detail) ways in which compliance with 'the regs' can be achieved. But failure to comply with the Approved Documents does not necessarily equate with failure to comply with the regs. So 'building according to the regs' is a rather broad concept. And building according to the Approved Documents is very dull.