Adding sockets to an existing radial supply in a garage

[Hinksy]

Hello all, I’m new to this forum! I work in commercial electrics (NVQ level 3, HND etc) but not domestic. I am confident to carry out basic domestic work but not familiar with the regs such as Part P etc.

New build house, 17th edition amendment 3 consumer unit.
I have a detached garage fed from the house consumer unit on a 16A, RCD protected MCB.
This is run in 2.5mm SWA underground into the garage and terminates into a double socket, with a 5A fused spur (FCU) for lighting.

As I understand it, I can run several sockets from the socket in the garage as a radial, protected via the 16A mcb in the house and this is not notifiable under part P. Is this correct? I would like to run all of this in singles in conduit for neatness and safety. Can anyone see a problem with this?

Installing a CU is notifiable, but what about a garage CU feeding the sockets and lighting? Technically, this is still on the existing circuit from the house and performs the same job as a FCU for the lighting so on one hand I don’t see it as notifiable, but on the other a new CU is notifiable!

So I am asking can I install a garage CU in place of a FCU without any notification or should I just leave the lighting on a FCU to avoid the notification issue entirely?
Thanks in advance!

 

[JBW175]

What’s your maximum demand for the garage? What loads you going be running?
Any extraneous parts that require bonding? Etc...

I’d look at all of that and then design accordingly.

 

[Hinksy]

What’s your maximum demand for the garage? What loads you going be running?
Any extraneous parts that require bonding? Etc...

I’d look at all of that and then design accordingly.

Very little demand, just want the extra sockets for convenience. A freezer at the back, dewalt charger etc. No water or oil or gas or anything like that so no bonding needed. It’s literally a brick shed with a 2.5mm SWA cable running into it!

 

[radiohead]

The part P document can be downloaded and read in a few minutes, it's not rocket science. And with a few exceptions (additional protection and distribution board construction) Bs7671 regulations do not distinguish between commercial, industrial and domestic.
It always surprises me the number of 'commercial or industrial' electricians who post on here for advice on very basic wiring in dwellings.

 

[Hinksy]

The part P document can be downloaded and read in a few minutes, it's not rocket science. And with a few exceptions (additional protection and distribution board construction) Bs7671 regulations do not distinguish between commercial, industrial and domestic.
It always surprises me the number of 'commercial or industrial' electricians who post on here for advice on very basic wiring in dwellings.

I’m not really in need of electrical / technical advice.
There’s more than one way of skinning a cat as they say, so I just wanted advice on whether I can install a garage CU without notification or not seeming as it is an existing circuit fed from the house CU. If I did need to, then I could just keep the FCU and extend the radial circuit which is not notifiable. Just trying to avoid the red tape which is not something I would encounter on site!

 

[westward10]

As soon as you fit a consumer unit then red tape comes in to play. Crazy world of Part P.

 

[Hinksy]

As soon as you fit a consumer unit then red tape comes in to play. Crazy world of Part P.

Exactly as I thought. Even though it really doesnt make sense in this case. I’ll just leave the FCU for the lighting in place and extend the radial circuit for a couple more sockets around the garage. Thank you!

 

[7029 dave]

IMO, to fit a CU to this radial is a waste of time and money, 2.5mm on a 16amp ocpd, just extend the extra sockets to the radial.

 

[Hinksy]

IMO, to fit a CU to this radial is a waste of time and money, 2.5m on a 16amp ocpd, just extended the extra sockets to the radial.

Fine by me! Avoids the red tape, easier, cheaper... I’ll run 2.5mm singles in conduit for some mechanical protection. Looks better too IMO but that might be because that’s what I’m used to at work

 

[Dave OCD]

Just crack on mate, it'll look good done properly in conduit. With a 2.5mm SWA you could even upgrade the MCB in the house to 20amp if necessary.