I understand the sparks has done this already, but thanks for the reminder
Yep - this was done last year complying with the 17th edition regs. The non RCD domestic circuit would not be allowed by the 18th edition so this would need an RCD isolator in place of the isolator switch in the new CU. As always your electrician can advise and make sure any work is done to meet the latest regulations.
Just for completeness -
My sparks was talking about a clean earth …
Each existing spur / radial is earthed already, but to achieve a clean earth the sparks was suggesting taking a new earth wire from each spur / radial back to a new earth spike, which would also be connected to the new standalone CU fo those spurs / radials.
Understood. Not something I’ve bothered with, but I imagine it would be worth doing if you have an electrician who can instal it properly.
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One issue I had with an earlier sparks was arguing against the numbers, resistance I think in ohms, that the existing earth produced. I live in a rural location, with a sub-station 1/4mile away, and down-stepping transformer a hundred yards away. There are only residential buildings in the vicinity, but there is a busy farm yard down the lane. Which, I believe adds up to a relatively good clean source of electricity. Even so I can hear the difference in sound quality between weekends, evenings and weekdays.
Rural is probably good in this respect. Farms can run some fairly power hungry equipment, though. Dairy farms at milking time will be firing up regularly at milking time, grain driers at harvest time, etc.
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I’m pleased with rural location and fortunately the farm is not dairy and the grain dryer did not get used last year. 
As it happens I think the farm supply comes from a different sub-station.
I find the biggest problem from the farm next door is when the welder is being used
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Sort of on subject… Some guy in the office said the regulation method of UK house wiring is now a separate spur from each socket back to the CU with an MCB per spur. This is the method that’s popular on the continent e.g. France. It means a heck of a lot of mains cable is used and a HUGE CU is required; fuse per socket. On the other hand the mains flex used doesn’t have to be as thick as normally used on a ring installation. Also he says that twin-and-earth is no longer used with individual separate wires running from each socket back to the CU. Is this right?
Is your ‘guy in the office’ an electrician ?
Not a domestic type sparks no… He has some electronic engineering qualifications but not a ‘qualified’ sparks - no.
I’ve done some google research including some intros to the 18th edition (effective from Jan 2019) and no mention of any changes like this. Sounds like a load of…!
Yes - the 18th is a an update. Your colleague seems to be suggesting a whole change to the way UK electrical installations are carried out.
Usual Caveat - consult a qualified electrician.
Indeed - as they are ploughing around here I expect it to stRt up at any moment. There is little interest in no-till farming around here
I think we are talking about ‘radial’ circuits, ‘spurs’ are a particular type of radial, often taken from a ring circuit in the UK. Radials are common ‘on the continent’ but it would make more sense to refer to rings being a quirk of the UK, as no one else seems to use them in final circuits.
Rings are more economical on cable, probably why the Brits started using them and the higher rated protective device feeding them, usually a 32A MCB backed up by and RCD (pre 18th edition of the regs) requires the use of fused plugs, BS1363.
Continental system is more fail safe/user proof, and easier to fault find. An example of where the Brits didn’t necessarily get it right. Oh and did i mention the 13A plug is more likely to land ‘pins up’ than the continental alternatives for the unwary sock wearing occupier to stand on! Sorry had to get that one off my chest :0)
Any way I have not heard of any trend towards the use of Radial circuits for socket outlets in the UK. After all we are allowed to use them anyway, and many dedicated circuits, cooker point, immersion heaters, lighting circuits already use radials anyway.
One thing the 18th Edition of BS7671, ‘The IET Wiring Regulations’ is bringing our way is the AFD, Arc fault detection device. I look forward to reading the discussion on the sonic disadvantages of AFDs in the near future.
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Yes I read the section on AFD with interest. Audio/sonic aside I’ve had a couple of issues in my house where, when checking existing wiring, I’ve discovered evidence of arcing. One case there was a junction box where the inside was extensively charred around one terminal where the insulation had been trapped under the screw of the terminal. Must have been like this for years!
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I think, like most safety inspired devices, they are probably a good idea. As yet I’m not sure how we are going to accommodate them or test them for that matter. I understand that they have been around for a while over the pond.
But I’m sure the market will adapt to serve the burgeoning market.
Yes you can even get them on ‘the river’ for less than a ton! Sounds a good thing to me.
So, yes i think Radials are a good idea, limit the protective device ratings for each circuit, just they do else where, then you don’t need a fuse in the plug, which some people will manage to get wrong when replacing them, and get some benefit (not sure how great) of being able to distance noisy loads from sharing the same circuit as one’s prized HiFi supply.
Everyones a winner, except it will cost a little more to install in the first place.
Sparks in the house …
First stage of the wiring update, separate 2xCU installed … I can’t hear any sonic differences, except that the hum is back when the I turn the tv off.
Next stage is to run the independent earths from the sockets back to the main earth.
Good question…