Electricians - Do I need this signing off or to be done by an electrician?

Depends where you are, rules are different across the country. In England you can merrily DIY it, in Wales it is notifiable (Just a spur wouldn't be be as it is outside it will be), not sure about Scotland as its a different system with warrants.

Also, if the circuit already has an RCD then adding another one won't do anything other than give you two places to check if goes off. If it doesn't already have an RCD the I'd look to adding one to protect the whole ring.

It's England so sounds like should be ok then.

The extra RCD bit was to try prevent it tripping the downstairs ring main (which has fridge freezer on it) if there's a fault aith anything plugged into the outdoor socket (pond filter so running all the time) It should just trip the RCD fused spur. Although I am aware that sometimes the ring main circuit can still trip depending on sensitivity of the breakers.

Might be useful (Warwick Council blurb)

Electrical rules

I thought theyd stopped (or trying to) DIY electrical mods by wrapping them in red tape needing to ensure any mods are tested (Inspection and Test) for insurance/building regs purposes forcing you down the approved electrician route.

i don't think RCDs work like that, you're likely to trip both of them anyway (or lucky dip if one happens to react first)

How do those plug in RCD sockets work then, if I have one of those on the end off say abjetwasher and it trips or impress test then it doesn't trip the rest of the house?

I’ve not heard of precut or glanced Swa before. Surely that be a pain in the butt unless your cable run is exactly the right length?

On the Rcd front, if your use case is the ability to isolate the outdoor circuit from the internal one you are better off using a double pole switch,

OP@:

Need to install an outdoor socket

Reply:

In England you can merrily DIY it

That'#s not what I thought and that link to the rules (as provided by Warwick Council) would support my thinking

As long as the job isn’t within a ‘special location’ such as a bathroom or outdoors, you’re also allowed to install additional new light fittings, switches, sockets and even add a single fused spur to an existing circuit

Outdoors
Another high risk area is outdoors. Many DIY power supplies run to garages and pond pumps and are potentially dangerous. This is why outdoor electrical work is now strictly controlled and circuits must be protected by RCD and cables must be run in special external grade protective conduit.

You're adding a new spur outside, which is notifiable work. Based on the details on the Warwick Council site, you CAN do it yourself by notifying them in advance and then getting them to come out and check. You will of course have to pay for this. Or you can get an electrician to do it and certify the work

That sounds out of date. Outside used to be a special location but it was removed from list in England a few years ago. Only special locations now are rooms with a bath or shower or a room with a swimming pool or sauna.

There's quite a bit that's poorly worded in that Warwick council link so I'd take it with a pinch of salt.

What you could do is install the outside socket and run it back to a 13A plug instead of wiring into the back of an existing double socket. This would not be a spur and wouldn’t require notification.

No point in having two RCDs (it won’t hurt anything) but it won’t have any impact on which one trips first (which is usually the house one, since it’s better quality and already has some earth leakage in it). You might not be able to test the RCD in the socket as the test switch just leaks some current to earth.

That sounds out of date. Outside used to be a special location but it was removed from list in England a few years ago.

Good call. The official Part P document doesn't mention outooors at all

Running a spur off an internal ring sounds expedient but does not sound neat.

Consider a separate circuit for your outdoor socket.

If the DB RCD and the RCD spur are both rated at 30mA (they should be) then the one in the DB will always trip first as it’s measuring earth leakage from all circuits connected to it, including your new wiring, the spur would be measuring just the new wiring so the DB one will get to 30mA first in the event of a fault

You’re adding a new spur outside, which is notifiable work. Based on the details on the Warwick Council site...

Definitely out of date. The only things to require Part P notification , in England, are a new circuit, additions in bathrooms and new consumer units.
I’m a bit intrigued how the OP is going to get ‘pre-cut and glanded’ SWA. Never heard of such a thing,and do you realise the size of hole you’ll need through the wall to get the gland through - probably 40mm, when a 16mm hole would be fine for the cable alone. How are you going to terminate the gland inside?
The easiest option is to drill a 10-16mm hole through the wall from the inside of the back of the socket you are feeding it from. Then fit an IP65 rated adaptable box where the hole comes out. Use 2.5mm T+E to get through the wall into the outside box. Gland your SWA into the bottom of the outside box, join the 2 cables (put now for easy reading, but do it last thing). Makes sure the armour is earthed (at both ends is preferable). Attach the SWA to the wall, attach new IPXX rated socket outlet, gland into the bottom of the socket, test the earthing, test the RCD, make sure the bonding is good. Fill in your minor works certificate. No council involvement at all.
A better option would be taking the power from a switch or fused connector, then the outside socket could be isolated if ever it started leaking water, though it's rare for them to leak if fitted properly. The above advice about a RCD socket outlet holds true, an extra one isnt needed, just use a normal IPXX socket.

It shouldn't be a huge amount of money so I'd pay someone with the correct accreditation if I was you, people will pay a mechanic to carry out minor repairs to their car or even a bicycle but will diy an electrical job. 🤷‍♂️

https://www.electricalsafetyfirst.org.uk/guidance/safety-around-the-home/electrical-diy/

https://www.hse.gov.uk/electricity/injuries.htm

Not worth it for a few hundred quid.

@nickjb

Only special locations now are rooms with a bath or shower

The whole bathroom? My interpretation was only work within the zones around the wet areas were restricted.

Yes, slightly lazy shorthand from me as we were talking about outside sockets. Within a bathroom there are three zones defined by their distance from the bath or shower. Special Location doesn't apply to the whole room, but if you are working in a bathroom you do need a better understanding of the regs.

The whole bathroom?

The zones mean that most UK bathrooms end up entirely within one of the zones.

@nickjb Thanks, just wanted to check I hadn't got the wrong end of the stick after adding a spur (predominately outside the bathroom) to add a heating element to a towel rail (and for future if I add a shaver socket).

@thebrick My bathroom is probably below average size but its still got a whole wall that is outside the zones

It shouldn’t be a huge amount of money so I’d pay someone with the correct accreditation if I was you, people will pay a mechanic to carry out minor repairs to their car or even a bicycle but will diy an electrical job.

not necessarily the same people though!

as I understand it the rules only become an issue when you move house (I guess if you did a bad job and someone got electrocuted or your house burned down it might cause some difficult conversations too but that’s equivalent to doing something stupid fitting new brake pads).  So your options are 1. Get paperwork right first time; 2. Hope nobody spots (cares) it’s a new addition when you come to sell; 3. Get it retrospectively inspected (which might be to new standards by then); 4. Remove the uncertified wiring before the sale.

as I understand it the rules only become an issue when you move house

when I bought my house in 2007, a small note on the ‘enhanced (pointless waste of money) survey’ said electrical inspection would be advisable.
That was the end of it.

if a home buyer is put off purchasing a house because a spur didn't have the right signooff they probably weren't going to buy in the first place.

can't remember the exact name but with our place I had a sparky in to do a full inspection and advise on upgrades when we moved in. but I knew our house was of the age you would expect it to be needing a rewire