Adding sockets

From DIYWiki
Revision as of 23:06, 14 July 2010 by NT (talk | contribs) (Cable Choice)
This page is Under Construction
Whilst all Wiki pages are subject to continuing improvement the author(s) of this page have included this disclaimer to alert the reader that the page may be particularly
  • incomplete - important sections may be entirely missing
  • inaccurate - significant facts and figures may be quite wrong
  • misleading - the text may not convey the author(s) intended meanings

In particular treat any safety-related sections of the text (e.g. relating to electrical work) with great caution.

If you are thinking of editing this page please be aware that the original author(s) of this page may be actively working on it at this moment, so changes you make may clash with theirs. (The Wiki software will warn you of conflicts if this happens.) Checking the page's history tab for frequent recent edits can warn you if changes by others are likely.

(this is a draft outline - feel free to add topics you would like to see covered)

This article covers the ways in which you can safely extend existing socket circuits to provide more outlets.


How many sockets?

Extending radial circuits

Extending ring circuits

New sockets can be added as part of the ring, or as a spur. Itsv ery much recommended to add them as part of the ring where this is practical. This means breaking the existing ring, and often adding a bit more cable.

A relatively easy way to add new sockets as part of a ring is to cut the existing cable run and fit 2 new sockets, one to each end of the cable, then link the 2 with a new piece of cable.


Sometimes running a single piece of cable from an existing point in the ciruit to a new socket is the only practical option. This is called a spur, and is subject to some limitations.

  • an unfused spur should only feed one single socket
  • a fused spur can feed an unlimited number of sockets. Many multi-way sockets have a fuse built in to provide the needed fusing.

Many single spurred sockets have been replaced with a double socket. This is not regs compliant, but is common.

Cable Choice

2.5 mm^2 the most popular socket circuit cable. Its sufficiently rated for 30/32A ring circuits as long as its not buried in 100mm or more of insulation. Its also good for 20A fused radials as long as its not buried in 100mm or more of insulation.

4 mm^2 is used for 30/32A radial circuits, and 30/32A ring circuits where the cable will be buried in insulation.

1.5 mm^2 cable is sometimes used on radial circuit where the circuit is fused at 15A and the cable won't be buried in 100mm or more of insulation. Where the cable is buried, 1.5 mm^2 can only be fused up to 10A. 1.5 mm^2 is typically used where an old immersion heater feed is reused to supply sockets.

Socket Positions

Cable Routes

  • describe allowable zones

RCD Protection


Circuit joins

Junction boxes

Extending cables

Disused cables

See also