Spliting into Multiple smaller rings options - comments please

[DmsF]

Hi,

I have 2.5mm tw+e on a ring which has now been heavily insulated. (After the wiring work unfortunately) It is not really an option to rewire in 4mm back to the CU, or sufficiantly extract enough of the wires above the insulation. It serves two bedrooms (5 doubles apiece), currently with a 32A RCCBO at the CU.

Looking for comment on the acceptability of dividing it into two separate rings in 2.5mm with either 20A or 16A RCCBO serving each room independently.

Taking it a stage further - is it beneficial to plan for putting each other non-kitchen room on own ring with 20A RCCBO? Or would this look excessive?

(the property is not 4mm friendly - so I would prefer to get a safe, quality 2.5mm solution, and undertsand that I need to recognise that substantial insulation will be needed to keep runing cost to acceptable levels)


Cheers,
DF
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[malcolmsanford]

There is nothing technically stopping you from protecting the ring with a 20amp protection device. I know what appendix 15 says but they are more informative than anything. As long as you mark it at the CU ring final circuit.

Would you consider 10 x double sockets in a bedroom enviroment needing more than 20amps? Again the same thing about all other non kitchen rooms would 10 x double sockets be needing more than 20amps. IMO no I think 20amp in a non kitchen enviroment is ample. In fact now I would wire all sockets non kithen in a 2.5mm^ 20amp radial. Easier for testing and installing.

Change the ring to 20 amp a leave it as that

 

[telectrix]

off top of my head, think 17A for 2.5 with insulation over 100mm method 101 , so double that for a ring, 34A on a 32 MCB. if insulation under 100mm it's method 100, 21A double to 42A. that's well in. can't see you pulling 34A i9n bedrooms, but if ref. method 101, you could drop the rcbo to 20A or 25A to be on the safe side.

 

[telectrix]

malcolm, you beat me to it again!LOL

 

[malcolmsanford]

Joys of polishing a chair in the office mate.

 

[Jimmyb]

A wire within a ring final only has to be capable of carrying 20A so long as the insulation is less than 100mm and clipped to joist or wall ect (Ref Method 100) then its ok on 2.5mm and 32amp mcb