Electrical – Wiring gas hob with electric ignition to mains

I assume your in the U.K as this sounds like a typical set-up for cookers in a kitchen area. The circuit feeds a control switch or cooker unit switch which may incorporate a one socket-outlet. The rating of the circuit depends on the current demand of the cooker. A 32A circuit breaker is normally sufficient for cookers up to 15kW. Wiring a cooker circuit with a rating more than 15A but not exceeding 50A may supply two or more cooking appliances where they are installed in one room. The cooker switch should be installed within 2m of the cooker but not directly above it. One switch may be used to isolate two cooking appliances where they are installed in the same room but neither are more than 2m from the cooker switch. A minimum cable size of 6mm flat twin & earth cable can be used for a typical cooker circuit (from the CU) with a maximum load of 15kW with a maximum cable run lenght of 28m (installed above a plasterboard ceiling covered by thermal insulation not exceeding 100mm thick).

In summary make sure to check the new appliance is the correct power/current rating. However normally to replace like for like is perfectly fine

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.