I had a gas safety check on a Bosch 24i combi and the man said that the
pressure relief pipework was sub-standard as it simply runs from the boiler
to the floor with the exit inside rather than an external exit.

Can someone please tell me what the Building Regs require as I am thinking
of correcting this myself (especially as the main work is do drill a hole)?
EG is it 15mm or 22mm pipe, what are restrictions on the exit, such as is it
downward facing etc etc.

Also where could I read or access these regs?

I even have the original Bosch Installation instructions but they dont
mention this pipework beyond the boiler

Thanks

Simon