[Closed] Garage electricness help

Convert the socket circ to à ring main but make sure the supply to the main cu is aproàtly sized.

So that is as simple as just joining the two existing sockets and putting the two extra in between?

It'll also depend on the supply to the garage consumer unit (which may or may not be what TheBrick said)

If that's a 32A circuit breaker (photo's a bit blurry) then it could be too large for a radial socket as fitted. You need someone to take a proper look

Cable size is the key.
I looks like you have 2.5mm T+E cable, in a ring, feeding the sockets. If so, then you need to extend the ring to the new sockets.
However, it looks like you havent got any RCD protecetion.
All new socket outlets must have socket protection now.
In your case, I'd be tempted to keep the cabling on the surface, and buy 2 sockets with in built RCD protection (@£15ish), and then you comply.
Or, you can remove the main switch, and put an RCD in its place, and have RCD protection for both the lighting and all sockets.
Or, buy an RCBO, to replace the 32A circuit breaker, and have the sockets alone RCD protected - possibly the cheapest option there, as RCBOs are typically £15-25 each. I'd also downgrade it to 20Amp too, so you dont have to extend the ring, and can spur off to any socket just with the one cable.

It looks from the photo that the consumer unit is fed by a piece of twin and earth and you have a socket below and possiblly a socket somewhere else as the two cables coming out the right hand upper side look like different sizes - one probably being lighting.

A 32A MCB is too big if the cable is 2.5FTE but not if it's run in 4mmFTE. If it is 4mm, all you need to do is run cable from the original socket to another, again using 4mm FTE.

If it's 2.5FTE then you can either make the circuit a ring or change the MCB to one that is smaller (20A will do).

A ring is more complex to do as you need to run from the existing socket to any new ones, then either to the end socket of any others already in place or, if there aren't any, back to the 32A MCB in the consumer unit.

I see that the consumer unit has a main switch rather than an RCD. This is probably due to the garage being fed from an RCD protected circuit on the main house consumer unit. If not, it should have an RCD in place for shock protection.

Job looks neat so I would guess it was done originally by an electrician rather than being a DIY job.

Rich.

PS - the assumption is that the socket at the bottom does not have any cables running from it apart from the one we can see. If has, then it probably is already a ring. In this case, you can spur off the socket but you can only add one double socket outlet per spur unless it's a fused spur. Any chance of a wider angle photo?

Job looks neat so I would guess it was done originally by an electrician rather than being a DIY job.

Maybe, but should the cable not be in surface conduit?

Marko

You could argue the case for it being in conduit. It's really a case of whether the cable requires the additional impact protection that a conduit gives. In a garage there are often tools, bikes etc. that could damage the cables so yes, conduit would be preferable. However, if the CU and sockets are not vulnerable then probably not.
Personally I'd use conduit but I still think it's neatly done compared to a lot of stuff I've seen.

a socket somewhere else as the two cables coming out the right hand upper side look like different sizes - one probably being lighting.

Yes, the socket below is a dead end, as is the other fed to to right and the smaller cable is lighting. Also correct, the garage is being fed from an RCD protected circuit on the main house consumer unit.

At the moment I'm thinking best option may be just to extend the existing ones to a more convenient location (behind plasterboard), presumably there is no harm in a belt and braces approach by replacing with the RCD ones as suggested.

I wouldn't bother. The RCD in the main CU protects the sockets. In a fault situation you can't guarantee the local rcd will trip first, it will be the most sensitive that does. This could be the one in the main CU anyway.

Check your cable sizes then extend as required as a radial rather than a ring, changing the MCB to a 20A if it's 2.5mm or leave if its 4.0mm. Job done.

Rich.

isn't converting a spur into a ring notifiable under Part P? apologies if not its been a while since I grappled with this while sorting out my own garage. Strictly speaking I know the OP didn't ask about this, but it might be worth highlighting whether or not his options are genuinely DIYable

isn't converting a spur into a ring notifiable under Part P?

Pretty academic as no one will notice esp if the current stuff is the new cable colours.

Rules have been relaxed quite a bit and very little is notifiable now. This job won't be if that unit is fed from the house cu abd already fed protected.

Looks like a 32 on the MCB. Will check the cable sizes, the clips say 4-6.

You don't need to notify for adding sockets and fused spurs to an existing ring or radial circuit provided it is not in a kitchen or "special location" ie a location containing a bath or shower, swimming/paddling pools or hot air saunas.

Rich.