Ring main extension

[Terrywookfit]

Is there any reason that I could not use 4mm2 cable to extend a ring final to supply 4 or 5 new sockets.
I have half a roll of 4mm but no 2.5mm.

 

[EFLImpudence]

No reason at all.

Although you do not need to extend the ring if using 4mm², a single spur (or spurs) in 4mm² to the 4 or 5 new sockets would be fine - assuming installed by Method C - clipped direct or buried in masonry.

 

[blup]

Is the circuit rcd protected?

Blup

 

[Terrywookfit]

No.
Old Wylex Cu with cb's.
There are no spare ways , otherwise I would have put a radial in.

 

[flameport]

No RCD = no extension of the circuit.
All socket outlets require RCDs, as do most cables concealed in walls.

 

[ericmark]

@flameport is correct, regulations are not retrospective so what has been fitted can remain, but anything new should comply with current regulations, however regulations are not law.

I have asked the question why RCD FCU and RCD sockets do not have the BS EN number listed in the regulations to which RCD's today should comply with.

I personally can't see any reason for not fitting a RCD FCU other than wrong BS EN number. But again personally I swapped my old fuse box for a consumer unit with all RCBO's. A RCD FCU costs around £15 and a RCBO around the same clearly depends on make used, but seems daft to fit some thing which will be made redundant once distribution unit is upgraded.

There are laws where people work, and laws for rented accommodation which if we ignore we could get caught out, some laws also apply to owner occupied, but unless you injure or kill some one, seems unlikely you would get caught, and as to rules, well if we want to comply with BS 7671 may as well close this site, as very few DIY people could do the inspection and testing required.