minor works cert for new circuit doubled up from an existing mcb??

[telectrix]

if your new work requires RCD protection in order to comply ( e.g if you are burying cable in a wall < 50mm deep etc., etc.) then you must either fit RCD/RCBO to the circuit, or an RCD FCU to your new work.

 

[GT1]

interestingly the diagram on page 425 of BGB shows socket outlets wired downstream of an FCU wired in 1.5mm....
Makes perfect sense when thought about, but woulve triggered a trip to the van to check the book if i'd found it on PIR (ECR)..!