Advice on outside wiring

[Field954]

Hi,

I’m new to the forum and am seeking some advice please.

I’ve picked up a job that another electrician has abandoned, the job is to ‘finish’ the electrics however there’s quite a bit to take in/check.

The original electrician has ran a 2.5 armoured to an outside garage but not connected up either end yet. The client was advised that one end of the cable would be connected up to an inside socket and the other end would be connected to a new CU in the garage!?

At the minute the client runs an extension lead from a double socket in the house to the garage which powers a lighting circuit, the garage door and plugs.

The client is adamant what he has been told by the previous electrician can be done however I’m questioning myself hence why I’m seeking advice. Is the previous electrician right to do this?

Every garage CU I’ve ever done has been powered via an armoured back to the main board. The client has spent a lot of money on the house and isn’t wanting any chasing done as not wanting to redecorate. Bit of help/advice would be great please.

Cheers.

 

[pc1966]

You can power the garage CU from a 13A plug via the cable, it is not a great idea on many fronts, but nothing intrinsically unsafe about it.

However, you can't terminate SWA in a 13A plug! It would have to be glanded to some box and then suitable flex taken to the plug, or you gland to an FCU back-box to wire from there, etc.

I suspect the only reason for not taking the SWA to the main CU is they wanted to avoid part P requirements?

 

[pc1966]

Is the new cable able to reach the CU? If so a separate MCB to feed the garage CU with (I presume) RCD or RCBO protections is better.

If it won't reach, but you could run SWA from house CU to where it currently ends up then you could join them using a resin joint. Bulky and a bit weird for indoors use but it is maintenance free!

 

[nicebutdim]

The client is adamant what he has been told by the previous electrician can be done however I’m questioning myself hence why I’m seeking advice. Is the previous electrician right to do this?

Sounds like the sort of client I'd want to ensure no ambiguity existed with, prior to accepting the job. On the basis of your post I can't help wondering why the original spark isn't going to be completing the job.

 

[littlespark]

The biggest problem I see is something in the garage tripping out the entire downstairs sockets.

I’d be planning around possible loads… is it just a few lights, garage doors and an outside freezer…. Or is there going to be a hot tub plugged in, or a load of heaters??

 

[snowhead]

The client is adamant what he has been told by the previous electrician can be done however I’m questioning myself hence why I’m seeking advice. Is the previous electrician right to do this?

It doesn't matter what the previous, missing in action Electrician said, or didn't say, promised or quoted for.
Or what the Client won't pay for.
What matters is what is needed to complete the abandoned job, if it can't be done to the regs and in a professional manner that has no future issues and at a price acceptable to both parties, then it's time to walk away.

As Nicebutdim, I wonder why the other Spark walked away.?

 

[timhoward]

Assuming the cable length doesn't create a volt-drop or ADS issue there is nothing 'wrong' with terminating the SWA in a wiska box and going through the wall to a socket. Then stick a an FCU the garage end.

You just need to make the customer aware of the shortfalls of this design and ensure they accept that.
13 amp limit outside. And if a shared RCD he'll lose half the house if there's a fault outside.

Is the socket circuit inside a ring or a radial, and what is the protective device (e..g B16, B32 etc.)
It would be unusual and horrible but I suppose it might be compliant to have a garage CU with a B10 and B6 in it...
Personally I'd avoid going that route.

 

[pc1966]

The client was advised that one end of the cable would be connected up to an inside socket and the other end would be connected to a new CU in the garage!?

I interpreted that as plugged in to a socket, but maybe they ware making it a spur? In which case not in keeping with RFC regs if it has more than double socket on it, and as above having anything permanently wired in to house sockets is a nightmare if faulty. At least with 13A plug, or DP switching FCU, you can isolate the garage feed and allow house sockets back on.

As I said not a great idea but i was thinking of the problem as technical. Others have pointed out there might be more issues with client and/or original spark's promised solution to be careful of.

 

[littlespark]

I was reading an older thread on here, much the same issue, when someone suggested speaking to the old electrician….

The OP replied with “do you know a good clairvoyant?”

 

[Field954]

You can power the garage CU from a 13A plug via the cable, it is not a great idea on many fronts, but nothing intrinsically unsafe about it.

However, you can't terminate SWA in a 13A plug! It would have to be glanded to some box and then suitable flex taken to the plug, or you gland to an FCU back-box to wire from there, etc.

I suspect the only reason for not taking the SWA to the main CU is they wanted to avoid part P requirements?

Yeah I think the original electrician was trying to do this job quickly and a bit rough too by the look of the way the cables are.

I’ll gland one end to an FCU in the house next to the double socket and then the other end to a socket in the garage and then use an FCU for the lights.

 

[Field954]

Is the new cable able to reach the CU? If so a separate MCB to feed the garage CU with (I presume) RCD or RCBO protections is better.

If it won't reach, but you could run SWA from house CU to where it currently ends up then you could join them using a resin joint. Bulky and a bit weird for indoors use but it is maintenance free!

New cable won’t reach the CU unfortunately. I’m going to take it to a FCU and run it from there.

 

[Field954]

Sounds like the sort of client I'd want to ensure no ambiguity existed with, prior to accepting the job. On the basis of your post I can't help wondering why the original spark isn't going to be completing the job.

After looking at the wiring I think I can see why.

 

[Field954]

The biggest problem I see is something in the garage tripping out the entire downstairs sockets.

I’d be planning around possible loads… is it just a few lights, garage doors and an outside freezer…. Or is there going to be a hot tub plugged in, or a load of heaters?

 

[Field954]

The biggest problem I see is something in the garage tripping out the entire downstairs sockets.

I’d be planning around possible loads… is it just a few lights, garage doors and an outside freezer…. Or is there going to be a hot tub plugged in, or a load of heaters??

Nothing huge, garage door, lighting circuit for 2 lights and a socket for power (not used for heaters or hot tubs etc).

 

[Field954]

It doesn't matter what the previous, missing in action Electrician said, or didn't say, promised or quoted for.
Or what the Client won't pay for.
What matters is what is needed to complete the abandoned job, if it can't be done to the regs and in a professional manner that has no future issues and at a price acceptable to both parties, then it's time to walk away.

As Nicebutdim, I wonder why the other Spark walked away.?

Totally agree, not enjoyable picking up work that others have left, client is the main focus and to keep happy as well as keeping everything safe. Job is on Thursday so should be able to get stuck in and have more of an in-depth look of how the previous spark did things.

 

[nicebutdim]

Yeah I think the original electrician was trying to do this job quickly and a bit rough too by the look of the way the cables are.

That's an easy conclusion to reach and, admittedly, my own first thought was that client may not have been happy with work carried out.

If this was the case, alarm bells would be ringing at the client being adamant you work to the previous spark's recommendations.

Tread carefully.

 

[Pretty Mouth]

This sounds like what I see in a lot of recently built properties. Spur from downstairs ring final to the detached garage via SWA, with a FCU at one end or the other for overload, plus another for the garage lights. Sometimes they put a garage board in the garage as well as the FCU in the house, which is a bit unnecessary IMO.

Nothing wrong with it really, but perhaps there are better ways to do it. One client did manage to pop the fuse, though he was using the garage as a gym in the winter and had 4kW of heating going on in there.

 

[DefyG]

Nothing huge, garage door, lighting circuit for 2 lights and a socket for power (not used for heaters or hot tubs etc).

Its not just the loading, if a fault develops within the garage the whole RFC will trip its RCD and if a split board other circuits too.