Garage Electrics

[Bobby10]

Hi, moved into a bungalow a few months back and was looking at sorting the electrics in the garage. The main unit is an older style consumer unit with fuses.

There are 2 6a for left and right side lights in the house.

There are 3 30a for 2 rings left and right side and 1 for cooker circuit.

Then there is a 15a fuse for the boiler I think.

There is a 40a Mcb fitted into it as well which is for the shower.

Looked at the wiring in the house and its a fair old mess. There is power adapters running power adapters running all sorts.

I removed all these and left it with just the sockets.

There is a cupboard in the hall and a 4 terminal junction box with a cable going into it and just stopping. Then there is a single socket at the back of the cupboard in the kitchen with a spur which goes into a junction box then on to another junction box and goes off to the boiler. There is also a connection to the alarm system from this.

As for the garage. From what I can see at the moment there is a 2.5mm twin and earth cable coming from in the attic somewhere running out to the garage. This then goes into a square metal box. This then runs into a single socket and about 4 adapters plugged into each other. There is also 1mm cable coming out and going into a breaker for the lights. When the breaker is off the electric for the socket still works but the lights don't.

The guy was using a good few different things in the garage, there is a circular saw, band saw, polisher, drill and he had a tumble dryer. There is 2 strip lights as well. When the saw is turned on the lights flicker.

I have not yet looked to see where the 2.5mm comes from in the attic but will be doing this. I have not been using any electrics in the garage at all until I investigate it properly.

I assume it will be a spur from 1 of the mains rings in the house. Will need to make sure though. Or it could be one of the 30a fuses direct from the fuse box. If its the 2nd it will be running about 8 meters in the roof then about 6 meters to the garage. The cable just comes out the roof of the house and is held up by wire there is no protection on the cable just 2.5mm twin and earth exposed to the elements.

Would be looking at having between 2 and 4 double sockets in the garage. Only 1 item would be used in the garage at any given time but there would need to be head room in case someone turned more than 1 thing on at any given time. There are 2 lights in the garage and an outside light. Be like a hand drill or lawnmower or circular saw being used.

Will this need taken out and redone. Or if it is made safer with the use of rcd protection. Or the use of a consumer unit in the garage?.

 

[Taylortwocities]

It sounds like you need an electrician to review what you have there.

Most (original) garage electrics are provided by a spur from one of the house ring finals to a double socket and that is all that can be supported on a ring, unless you are prepared for the total load to be only 13amps. Original garage lighting is usually a feed from one of the house lighting circuits.

If youy need more than this then an additional dedicated circuit would be needed to support the larger load that you requirments would need.
Also these sockets will require RCD protection.

In all, you would need
a new dedicated sub main from the supply, or the main fuseboard
probably a mini consumer unit to provide circuit protection for your 4xdouble sockets (probably a ring final or 32A radial)
you may want to leave the lights on their existing feed, or run it from the garage CU.

All of the above is notifiable work that really needs a registered electrician to carry out, unless you are already a competent electrical DIYer who can install and test to the recognised Wiring regulations?

I would get a couple of electricians round, so they can see what you have there, and get some quotes.

PS

Then there is a 15a fuse for the boiler I think.

Maybe, more likely for the immersion heater - if you have a hot water tank?


and also

There is a 40a Mcb fitted into it as well which is for the shower.

I hope that you have an RCD on that circuit!

 

[Bobby10]

Hi, thanks for getting back. The house was sold with a home report and nothing was mentioned about electrics. There is only 1 cable out to the garage which is 2.5mm twin and earth.

There is no water tank in the house it has recently had a combi boiler installed. However as I said the wiring to this seems to be coming from a spur in a socket in the kitchen.

Looks like just a 40a mcb installed. Then the cable runs around 8 meters through attic into a 45a pull cord. Then from there into the shower.

Seems weird that they did not have a mixer shower after installing a new combi boiler as the shower is about 1 meter away from the boiler. Seems more logical than running a 10 or 12 meter length of cable.

I think that there should be blueprints made with every house. Which give locations of all plumbing and electrics. Also the design to show what is what. It would seem that the electrics have been added to and altered in the house.

I am in Scotland though and there really isn't any laws on what can and can't be done. So in effect a plumber or kitchen fitter can do electrical work and so can anyone on a DIY level.

The guidelines for my council say that you can pretty much rewire your house and power to external buildings without notifying anyone. Only if you are in a block of flats or 3 storied building do you need to notify anyone.

Unfortunately what this leads to is what I am seeing in this house. Where the boiler fitter has not done a very good job of wiring it up. Whoever wired up the extension needs shot. The garage has too much in it for what is supplying it. If it is a spur it should only have 1 socket and a light. Not adapters and power tools a plenty.

Would be tempted to rip out all that is there and get it done from scratch. When I was under the floor there was a fair few cables lying around tied up and not used. Also 2.5mm twin and earth tied together as they obviously ran out of cable and thought it would be ok just to tie extra cable to it.

 

[Bobby10]

Will double check the shower but pretty definite that its on an mcb. Surely the installer should have used a seperate board for the shower though. Like installed a rcd and mcb in a seperate 2 way consumer unit?. Or used an rcbo?.