Limitations of radial circuit

[Glyn1959]

Confused! I have read that a radial circuit using 2.5mm cable covered by a 20A mcb can serve an area of no more that 20sq metres.
How is this measured? Is the distance from the consumer unit to the area served by the radial circuit a factor?
In my case, the distance from the consumer unit to the garage/workshop is say 10m and the garage/workshop is approx 20 sq metres.
Is this condition ok?

 

[jj4091]

It is not the area served, but the current carrying capacity of the cable & the size of the protective device that is important. I presume from your description that your garage is supplied by a 20A radial, but what does it serve in the garage? If there is a small consumer unit for lights & a socket then you will be fine.

 

[plugwash]

it is the area the circuit serves, except in unusual circumstances I would take the area served as the total area of all rooms that the circuit serves.

just running through a room is not serving it.

 

[Glyn1959]

Hi, currently I have 1 light in workshop and 2 lights and 2 double sockets in the garage ... I plan to add my old consumer unit, (I am replacing my existing one) 1 additional light and 1 additional socket.
Would this be acceptable?

 

[Dippy]

I believe that its 50m2 max floor area and max 30m run assuming the new CU is latest spec.

 

[mikely]

My understanding is that the floor area limit was based on potential space heating demand on a socket final circuit. This is not really applicable to a garage.