Ring or Radial....?

[Noob2013]

Hi all,

Im am soon to be installing 4 double sockets and possible 2 wall lights in a new conservatory.

Was going to extend downstairs ring but a tad awakward and I'm not a lover of junction boxes if they can be avoided. The consumer unit isn't too far so just as easy to install a new circuit.

I'm debating whether to go for a 2.5mm ring, 2.5mm 20 amp radial or a 4 mm 32am radial. If the wall lights are required then will be fused down via a FCU.

Obviously less Cable to run with radial and I can't imagine there will ever be much load on the few sockets.

Opinions much appreciated

 

[7029 dave]

Not to my knowledge. If it has, it wouldn't bother me too much, i'd have no problem running a cable in such a low cavity wall again.

I am with you ENG, have dropped down many with rewires, and still would apart from the cavity boys messing it all up. lol

 

[Farmelectrics]

yes thers a thought dave free cavity wall insulation has changed this got it done my self last year the house is warmer but dosent help current carrying capacitys of any cables installed in cavity walls

 

[7029 dave]

TBH Farm, how many thousands of home's have been insulated the cables are not greatly affected.

 

[Farmelectrics]

no i agree dave but the bgb has derating factors ranging from 0.51 up to 0.88 depending what length of insulation your cable is sited in

 

[Noob2013]

Thanks for all the responses.

Quick update.

- 4 double sockets and 2 ceiling lights to install.
- Sockets only required for tv + 2 lamps
- Approx total length of run = 20m
- 100mm insulation in cavity (brickwork with plasterboard)

There is one spare way in consumer unit so my plan is to put in a 20A 4mm radial supplying 4 x DSSO's and 1 x FCU (to feed the light switch + 2 ceiling lights in 1.5mm)

If the loading of sockets is increased in the future then the MCB can be increased to 32A.

Cables will run underneath the existing floorboards then clipped to the joists in the new conservatory then up through the cavity with 100mm insulation. Only approx a total of 5m of cable will be surrounded by insulation, including the lighting cable fed from FCU.

Sound ok, any suggestions?

Thanks

 

[Octopus]

On the basis that the bonding is up to date and there is RCD protection in the CU that just leaves the EIC and LABC to do!

 

[Farmelectrics]

Sounds ok to me

 

[sparksburnout]

Joists in new conservatory?????

 

[specs]

I'd probably install a radial, whether it be a 20 amper or a 32 is down to you and your knowledge of the install mate.

Ditto mate