Adding a Spur Socket

A spur is a branch cable taken from the ring final circuit to feed one extra socket. It's the simplest way to add a socket without rewiring the whole ring.

What a Spur Looks Like

Ring main cableRRRRSpur cableS

The Rules

  • One spur per socket on the ring. You can only take a spur from a socket that does not already have a spur.
  • One socket per spur (or one double socket — it counts as one).
  • Spur cable must be 2.5mm² T&E — same as the ring.
  • The spur cannot loop back to form another ring — it must be a dead end.

How to Identify a Ring Socket

You need to check before taking a spur. At a ring socket, there should be two cables entering (ring in and ring out). At a spur socket, there's only one.

Important: Always isolate the circuit at the consumer unit before opening any socket. Test with a non-contact voltage tester before touching any conductors.

Non-Fused vs Fused Spurs

  • Non-fused spur — connects directly to the ring via a socket's terminals. Protected by the 32A ring MCB.
  • Fused spur — via a Fused Connection Unit (FCU) with a lower-rated fuse (e.g. 13A or 5A). Useful for permanently connected appliances.
⚡ Try adding a spur on the canvas