How to extend wiring for extra high current sockets/appliances in Utility room

Question

In our basement we have a metal double socket which I believe is wired directly into the Consumer Unit. We currently have these plugged in.

• fridge (750W, 4A max)
• washing machine (2400W, 11A max)

All works fine.

I now want to add 3 extra sockets:

• Tumble Dryer (2600W, 12A max)
• double socket above worktop for...
  • hoover, iron, etc

So increasing from two sockets to 5.

Qu 1: What is the best way to extend the existing double socket to add 3 extra sockets.

Current criteria:

• I am in the UK, so 230V AC.
• Running the washer machine, tumble dryer and iron all at once, would draw about 10A each, so hit the 30A limit, but that's probably likely all will draw that much at exactly the same time.
• I assume the ring main has a breaker of 30A (which I need to double check).

Assumptions:

• I can't use a spur from existing socket as this will pull too much current.
• It sounds better to continue this as a ring main rather than a radial circuit.
• Using a double socket for washer/dryer isn't great as they don't deal well with 20A+.
• Each major applicance would plug into a switchless single 13A socket.
• Each switchless socket would then connect into a 13A switch (above the worktop).

Qu 2: Can I just connect the 3 x 13A switches in parallel from the existing wires coming from the consumer unit?

Qu 3: I presume if I want a normal double plug/switch (above the worktop), I can add this in parallel as well.

Qu 4: Presume makes these changes will need me to get an electrician to certify it (even if I do the work myself)

Answer 1

Qu 1: What is the best way to extend the existing double socket to add 3 extra sockets.

You want to increase the total load from 15A to >27A.

You probably don't want the breaker tripping if you, for example, run the washer and dryer at the same time.

If the existing circuit is really a radial circuit with a dedicated breaker in the CU you will need to check

• The breaker rating
• The wire diameter.

If the wire diameter is small, you cannot increase the breaker rating without first replacing the wiring with a suitably sized new circuit. Under UK regs I believe you should get an electrician to do this work.

I can't use a spur from existing socket as this will pull too much current.

It depends what you plug in. The breaker should protect the circuit.

It sounds better to continue this as a ring main rather than a radial circuit.

Ring mains are typically 32A but I don't see creating a ring main as easier than upgrading a radial circuit.

Using a double socket for washer/dryer isn't great as they don't deal well with 20A+.

So long as the circuit is properly constructed, you should be fine. I certainly run those two appliances from a double socket.

Qu 2: Can I just connect the 3 x 13A switches in parallel from the existing wires coming from the consumer unit?

You should draw a diagram of your intended circuit. You don't wire switches in parallel. I guess you mean something different but you need to be clear.

You may be over-complicating things here. You can use normal switched sockets (even though inaccessible with appliances in place) and when necessary, just isolate the whole circuit using the switch on the breaker.

Qu 3: I presume if I want a normal double plug/switch (above the worktop), I can add this in parallel as well.

Yes.

Qu 4: Presume makes these changes will need me to get an electrician to certify it (even if I do the work myself)

As I understand part P, You can extend an existing circuit but you need an electrician to certify it if you create a new circuit. It might be no cheaper than paying an electrician to do the work themselves.