My through lounge is being replastered and skimmed. Is it advisable to extend the height of 2gang x 6nos of power socket to 450mm just by extending the existing wiring through a connector, and leaving the connector under the floor board.
Or, is it necessary to do a complete new rewiring to these points so that there is no connetor.
Why do you want to raise sockets to 450mm? There is no need to have sockets in existing installations at this height and often one finds that to raise the height means that
"522.6.1 Wiring systems shall be selected and erected so as to minimize the damage arising from mechanical stress, e.g. by impact abrasion, penetration, tension or compression during installation, use or maintenance."
is not complied with.
Many items like chairs, beds get wider as they go up and mounting sockets higher can mean these with bang into items plugged in to the sockets. You need to do risk assessment.
As to joining where the cables are not assessable then maintenance free methods must be used. i.e. nothing using screws as these can vibrate lose. Western role and solder with shrink sleeve final being epoxy resin filled can make a really good joint but this is hardly a DIY job. Solder on it's own is not good enough so for DIY maintenance free junction box is most likely way forward these hold wires with spring clips and also hold the cables in grips unlike the old Bakelite round JB's.
Crimping is also allowed but something must protect the cable and although self amalgamating tape and insulation tape may cover the cables and seal from damp ingress it can be removed without a tool so does not strictly comply. Shrink sleeve needs the job to be neat but is likely best method.
Of course if you move the socket it then must comply with latest regulations so if you don't have RCD protection already you will need it once moved.
Also needs minor works certificates so you would need to hire an earth loop impedance tester, RCD tester, and Insulation tester to fill in test results.
Seems a lot of work to go to. I would only do it if someone in the house was having problems with low sockets. Never quite worked out why 450mm recommended in a house and 400mm in commercial premises? If you read Part M there are a few items which do not make any sense. The thermostat needs mounting over 1200mm high as it needs readings and under 1200mm for access plus of course it's height will also effect how it works so following Part M has to be with some common sense and not strictly to the letter. Also they want socket 400mm up the wall but you are still allowed floor mounted sockets.
Items like isolators and consumer units have always been mounted on the high side to keep them out of the way of children and in the main that is more important than the old disabled visitor.
Unfortunately common sense seems to be lacking in many of our actions. I have just binned a load of silly plastic lumps my daughter bought and plugged into the sockets. She said "To stop kids getting a shock". What they did was disable the protective shutter system already fitted to British sockets and introduce danger rather than remove it. Caught kid playing with them. The size of these plastic lumps did not comply with sizes for British plugs and of course had no British standard yet the toy shops sell them and mothers buy them. Bad little earner for someone?
So don't just follow the books also think about if it is really a good idea!
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