garage wiring alterations

[andy_h]

Hi,

I've bought a new build house and it has a detached garage.

There is a single breaker on the house consumer unit for the garage which feeds a cable into the garage. This cable runs underground and comes up into a switch (inside the garage at the front) that seems to shut off all electrics, then runs via 2.5mm twin and earth to the back door where there is a switch that operates a single light . From this switch runs cable two more cables - one to a double socket and one to the actual light. (the switch seems to be doubling as a junction box)

Ideally, I'd like to put in another light at the front of the garage and a second double socket.

Is it OK/legal to cut the 2.5mm coming from the first switch (and going to the second switch) in order to do this, and could I do this via a second socket or switch - i.e cut the 2.5mm, wire both ends into the socket - and then another wire going to a second switch to a second light bulb? Or cut and put another switch (similar to existing light switch) and use this as a junction?

please see rather attached poor diagrams(I'm no artist!!)

 

[Spoon]

Welcome to the forum mate.

I presume the cable that supplies your garage is wired to the house CU. What size breaker is it wired to?
Does your house CU have RCD protection?
What is the earthing arrangement for the incoming supply to your house?
I don't like the wiring inside the garage. Can you take some pics of your house CU and wiring inside the garage and post them up please.

 

[Pete999]

Welcome to the forum mate.

I presume the cable that supplies your garage is wired to the house CU. What size breaker is it wired to?
Does your house CU have RCD protection?
What is the earthing arrangement for the incoming supply to your house?
I don't like the wiring inside the garage. Can you take some pics of your house CU and wiring inside the garage and post them up please.

If his gaff isn't that far from me I will go and have a butchers, PMd Andy for his location.

 

[Strima]

Photos are worth a thousand words!!!

 

[Gavin John Hyde]

My instinct looking at them pictures is it needs a bit of tweaking, the first switch as the op describes it I would change to a small cu - it would make things easier for him and others to understand rather than having it all off one circuit. and then run separate circuits from this new cu for the lights and sockets, this new small Cu being fed from the breaker in the house (assuming its got capacity and the cable is up to the job). We can then look at the earthing for the house and garage.

 

[davesparks]

Does the switch which operates the light incorporate a fuse by any chance?

 

[telectrix]

Does the switch which operates the light incorporate a fuse by any chance?

i was just thinking . is it a FCU. as it's a new build, the feed is probably 2.5mm T/E . done as cheaply as possible.

 

[Spoon]

I'll just wait for the OP to post some pics up. Then we should get more of an idea of whats going on.

 

[Baker1988]

I have seen this set up quite alot in the local housing association jobs. 2.5 t+e from 16A breaker to the supply side of the fused spur then from there down to a socket. Then 1.5 t+e from the load side of the fused spur to a pendant and a 5A fuse fitted in the fused spur all usually in conduit aswell.

Cheap way to do it but it is ok as far as i can tell.

 

[rolyberkin]

Same as standard new build around here, 16amp MCB, fed 2.5mm to the garage and then switched fused spurs to the lighting, conduit would be a luxury in the very expensive houses around here, most seem to be clipped direct!

 

[Pete999]

Hi,

I've bought a new build house and it has a detached garage.

There is a single breaker on the house consumer unit for the garage which feeds a cable into the garage. This cable runs underground and comes up into a switch (inside the garage at the front) that seems to shut off all electrics, then runs via 2.5mm twin and earth to the back door where there is a switch that operates a single light . From this switch runs cable two more cables - one to a double socket and one to the actual light. (the switch seems to be doubling as a junction box)

Ideally, I'd like to put in another light at the front of the garage and a second double socket.

Is it OK/legal to cut the 2.5mm coming from the first switch (and going to the second switch) in order to do this, and could I do this via a second socket or switch - i.e cut the 2.5mm, wire both ends into the socket - and then another wire going to a second switch to a second light bulb? Or cut and put another switch (similar to existing light switch) and use this as a junction?

please see rather attached poor diagrams(I'm no artist!!)View attachment 40763 View attachment 40764 View attachment 40763 View attachment 40764

Andy, I have sent you several PMs offering help, if you are nearby to me,so far I have recieved nill resoponse, I will offer my help again subject to location, if I don't hear from you I will form the opinion that you are un intersted or can't see my PMs.

 

[Spoon]

I don't think the OP will be coming back...
Obviously not a Terminator fan.

 

[andy_h]

hi all,

thanks for all the replies - fraid i've been too busy to get to computer though!

I think the setup is as several people say - cheap as possible new build - 2.5 twin'n'earth into garage from 16a breaker in house. (see attached) the first switch at the front switches all the power to the whole garage. this then runs a 2.5 TAE to the rear *light* switch , that seems to double as a junction box - with a split off to the socket and the switch output going to the single light.

so there's no 'propper' feed going into a consumer unit and distribution - its all just a wopping great spur really.

But, its not a workshop - all I'd really like to add to this setup is:

- a second light - ideally controlled from a switch near front (i.e. near the 'main' switch not the existing light switch)

- a socket near the front

- a security light (120w)

if i can get those in without re-wiring the whole damn garage / calling in a electrician I'll be a happy bunny. If i can't, I'll just live without the extra light/socket and security light!

By the way, as a teenager in the 80's , I'm a massive fan of the ORIGINAL terminator ! i like T1 the most - if felt like computer technology I could imagine - I felt the liquid metal was a bit of a cop out!!

pete - thanks for the offer .I actually live in peterborough, but tbh, if this is a big job I'm just not going to do it!

 

[Spoon]

Thanks for the reply.

- a security light (120w)

I'd check the max wattage allowed for an outside light. I think 120W is too much.

Well I may be wrong in that.. haha

 

[Spoon]

Looks like 150W is the max..
Building Regulations | Lighting | Planning Portal - https://www.planningportal.co.uk/info/200130/common_projects/35/lighting/2