(Its a new built (2015) house and weve just moved in so wanted to put enough in and not have to think about changing anything later on.)


sorry if its been mentioned already but the garage circuit, is it on a 16A mcb in the house consumer unit?

New builds these days seem to just have a 2.5mm t&e go into a whiska box which is then terminated onto a 2.5mm 3 core swa. depending on the garage demand, you might have to upgrade the cable from the consumer unit to the whiska box first.
 
yeah just checked and its on a 16a breaker in the house, and it does appear to be a 2.5mm t&e being fed. not sure about a whiska box as obviously this cable then runs behind the plasterboard.

i thought a 2.5mm was enough for a 16a radial circuit? after seeing the cable i know i cant uprate it to a 32a, which i wasnt intending to do anyway. But are you suggesting the 2.5mm and the 16a wont be enough for a few garage sockets?
 
2.5mm2 T&E can be used with a 20A breaker.
All depends on the installation method.
SWA is rated slightly higher than T&E.
Don’t like the idea of there being two 16A breakers in series, it’s a guessing game as to which would trip in the event of a fault.
As you intend installing extra sockets, and even intend using sockets for lighting, you will need to provide RCD protection.
Easiest method would be to swap the MCBs in the garage for RCBOs.
 
Thanks, so this is what i think im going to get ready.

new 20a breaker in the house cu (maybe an rcbo, my board is full and plan an extension later on, if i replace all breakers for rcbos i can gain 4 slots by removing the dual rcd parts)

new 16a rcbo in the garage (replacing 16a breaker)

new lighting rcbo????? not sure if this is needed.

radial circuit from the garage cu to the plugs.
 
Also i was thinking of wiring the external wall socket into an rcd plug and then into one of the double sockets on the inside. This would reduce the radial circuit by one permanent double, and the external could just be plugged in/turned on when used.
 
If the circuit feeding the garage is already RCD protected in the house by one of the dual slot RCDs, there will be no need for extra RCD protection in the garage.
No need for an RCD plug if the socket you plug into is already RCD protected.

Ideally the circuit feeding the garage should not be RCD protected, though it may have to be as you mention the T&E runs behind plasterboard.
 

Similar threads

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electric Underfloor Heating Electrician Courses Heating 2 Go Electrician Workwear Supplier
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Advert

Daily, weekly or monthly email

Thread Information

Title
Garage Wiring Advice
Prefix
N/A
Forum
UK Electrical Forum
Start date
Last reply date
Replies
28

Advert

Thread statistics

Created
Lee Mason,
Last reply from
Deleted member 26818,
Replies
28
Views
4,980

Advert