A friend while refurbishing his kitchen has completely boxed in all the pipework right up to and under his boiler (wall mounted combi) leaving no access to any safety valves, filling loop etc. I'm not a plumber but I suggested it was unwise if he needed access in a hurry or any work done but he just said he'd break it open if that's the case but is it in contravention of any regs and is there any particular danger to doing this when as he suggested he could always turn the gas and mains water off at the meter/stopcock?