Consumer unit full - what are my options?

sparkwright said:

... you could have all RCBOs instead of MCBs and two RCDs. ... This means you would have circuit breakers with their own individual RCD built in. .... This therefore means if there is an earth leakage fault, only the one 'RCBO' will trip, whereas before one RCD would trip taking out several circuits rather than just one. .... If you can afford it....

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Factually all true.

However, to put this all into context, when I think about the (tiny) number of times during the 40+ years I've been living with RCDs that I have experienced an RCD trip due to an earth leakage fault, and the (again, tiny) proportion of those (extremely few) trips which have resulted in appreciable problems or inconvenience, I have to wonder how much additional cost (for 'all RCBOs') can be justified to balance the consequences of not having 'all RCBOs'.

Kind Regards, John

I can’t see the value in changing that modern unit to an expensive metal rcbo unit.

Wait until the half height rcbo with arc detection come down in price.
Even have a led on front

My 17th edition consumer unit is also full after a loft conversion in 2016, just did an extension and they have bung in a small Axiom garage cu powering sockets oven and lights off a henleys block.

What I am not sure about is the consumer unit being plastic, but 4 of the slots are taken up with RCD's so swap the MCB's for RCBO will free up two or four slots, it is unlikely that some functions can't be combined, so it should be possible to get the extra slots needed.

As to cost, my RCBO were around £10 each, but does depend on make of board, so swapping 10 would likely cost more than a dedicated board for the car, but RCBO is better anyway as reduced chance of unwanted tripping, and if it does trip you lose less.

It is not best option as all options have plus and minus points, and not sure which would work out cheapest either, as if I swap a MCB for a RCBO I suppose I should also be testing that circuit.

Although no two circuits should share a neutral it's not unknown, so changing to RCBO could highlight an existing fault, however that is not really a bad thing.

Not sure about earthing either, it may be the car needs TT and house TN-C-S so mi I consumer unit may be better.

So there is no right and wrong just different opinion as to option best suited.