Garage Wiring

[IanNE]

I need to wire an adjoined garage to my existing house.

Whats my best option and way to go about it. I have a consumer unit fitted with two RCDs on two seperate banks of MCB's. Do I wire directly off one of the MCBs of existing consumer unit to garage or is it better to run off existing consumer to a new garage consumer unit... but this would end up being protected by two rcd's...

Any suggestions are appreciated, thanks..[/b]

 

[RF Lighting]

What are you planning in having in the garage? Are you after just a single light fitting in the middle of the room, or a home workshop with machinery, welders etc?

 

[securespark]

All depends what you need, circuit and load-wise, but generally, if the building is attached, I'd wire it back to the CU.

Unless you need loads of stuff.

Whatcha got?

 

[securespark]

****....

 

[EFLImpudence]

 

[securespark]

Wot you laughin' at, catty-puss??

 

[EFLImpudence]

You called.

 

[securespark]

My decrepit fingers are not as nimble on the old KB as you young whipper-snappers.

 

[IanNE]

It will have in it an electric garage door, three large strip lights, around six double sockets. quite a few power tools..

My only concern is, if anything trips in the garage it will trip the RCD in the house consumer unit, tripping the other MCB's..

I can easily run 6mm2 cable to the garage and then to a samll consumer unit in there. BUT do I connect to an MCB on the existing consumer unit OR prior to the existing consumer unit...

Also is plastic conduit required in a garage.

 

[bernardgreen]

It will have in it an electric garage door,

You do have another door that you can use during a power cut ?

My only concern is, if anything trips in the garage it will trip the RCD in the house consumer unit, tripping the other MCB's..

The MCBs will trip on overload of their circuits, not when the RCD trips out. If one or more MCBs do trip when the RCD trips you are likely to have a serious error in the wiring of the consumer unit.

I can easily run 6mm2 cable to the garage and then to a samll consumer unit in there. BUT do I connect to an MCB on the existing consumer unit OR prior to the existing consumer unit...

An electrician could connect the cable from the garage to a switch fuse powered from Henley blocks on the tails feeding the consumer unit.

Also is plastic conduit required in a garage.

Better than storing it in the master bedroom. It does provide the cables with some protection from flying objects in the garage / workshop

 

[ban-all-sheds]

My only concern is, if anything trips in the garage it will trip the RCD in the house consumer unit, tripping the other MCB's...

In other words your concern is that you have no idea how to design this all properly, with the right discrimination etc.

You are wise to be so concerned. And you would be wise to get an electrician.

 

[IanNE]

My only concern is, if anything trips in the garage it will trip the RCD in the house consumer unit, tripping the other MCB's...

In other words your concern is that you have no idea how to design this all properly, with the right discrimination etc.

You are wise to be so concerned. And you would be wise to get an electrician.

Thanks for the helpful reply, your a credit to this DIY forum.

 

[aesmith]

Do you have spare ways in the consumer unit?

 

[PrenticeBoyofDerry]

It's a fair point being made by BAS and with no disrespect to your DIY skills, it would be wise to employ someone with an understand of circuit design and a knowledge of inspection and testing as you will require test certificates. And possibly depending on the method of installation building control approval.

Electric kills and that is a fact, like it or not!

You could use an circuit from the CU that is not protected by RCD (cable mechanically protected) or circuit protected by RCBO to garage then depending on which of those methods used have either RCD protected garage CU or an unprotected CU. Then distribute sockets and light from there.
The circuit will need to be designed with loading, de-rating and voltage drop calcs.

 

[ban-all-sheds]

Thanks for the helpful reply,

No problem - glad you found it useful.

your a credit to this DIY forum.

Several hundred people think so.