getting electricity to my garage

[jackofnotrade]

planning on tidying up my garage with a new floor and painting it all and getting electric into it

I am planning on some strip lights and sockets

I may end up with a bench grinder and welder etc in it.

Is there any websites to learn the basics so i can try to understand what is required etc formulas for cable sizing etc so i know the electricain understands exactly what i want and it is done properly

any help would be great

thanks

 

[ban-all-sheds]

How does you knowing how to calculate the size of cables ensure that your electrician does it properly?

He will understand what you want done without you having to do the sums for him. If he doesn't then don't use him.

 

[jackofnotrade]

well i will need some sort of armoured cable to take from main cu to my garage to another cu and i like to know that the stuff is sufficient size to run a welder etc

would also like to know if the likes of a welder will require a seperate circuit etc

I have asked for some advice and would like to learn something along the way to make sure i dont get ripped off

 

[Steve]

If it were me, I'd run at least 10mm² for your anticipated demand. Depending on distance. Which you havent mentioned. If you can afford it, plump for 16mm². You only want to dig that trench once!

The welder - depends on its rating as to whether it needs a seperate circuit. Some will trip a B rated MCB, you'd need C rated back to the house DB if this is the case (or it may be better to skip the house DB and split the tails, with a cartridge fuse protecting the run the the garage.)

The feed to the garage should NOT be RCD protected, especially if you're putting in special circuits. The only RCD protection you need (provided all cables run on the surface or are armoured) is for the general use sockets.

 

[electronicsuk]

well i will need some sort of armoured cable to take from main cu to my garage to another cu and i like to know that the stuff is sufficient size to run a welder etc

That would depend on the size of the welder. My preference would be to run 10mm for future proofing, probably fed from a switchfuse henley'd into the main supply tails. Your 'electrician' may have other ideas, as he will be able to see the job, we can't.

would also like to know if the likes of a welder will require a seperate circuit etc

Again, that depends on the size of the welder. If it's fitted with a 13A plug then it will not require a dedicated circuit. If it requires more than 13A/3kW, it will need some sort of dedicated circuit.

I have asked for some advice and would like to learn something along the way to make sure i dont get ripped off

That's fair enough, but from where we're standing, the sort of questions your asking make it look like you plan to attempt this work yourself, and there is in fact no electrician involved at all. If you don't plan to carry out the work then there really is no need for you to be able to calculate cable sizes.

If you intend on doing the work yourself then you would have got a far more favourable response by being upfront and honest about it.

 

[jackofnotrade]

my garage is approx 8m from my CU in the house

I am planning to block pave my drive soon so am looking to get the cable layed before i do that.

If it is armoured cable could i run it just below the block paviors or do i need a proper trench to protect it?

cheers for the info

 

[electronicsuk]

my garage is approx 8m from my CU in the house

I am planning to block pave my drive soon so am looking to get the cable layed before i do that.

If it is armoured cable could i run it just below the block paviors or do i need a proper trench to protect it?

I'd suggest you run in a length of ducting so that your electrician can pull in a suitably sized cable at a later date. There's no point you installing something on our recommendation that your electrician may later be unhappy to work with.

Ideally you should be burying at 450mm deep, but if the ducting/cable is to be under block paving throughout it's entire length then there is little need to go so deep, as the chances of mechanical damage are low.

 

[jackofnotrade]

thanks for the reply, I dont plan doing this myself as i do not uderstand electrics and i am not qualified.

I do however intend to run an armoured cable to my garage before i do my drive way.

I am just interested in learning about the subject as like to know how things work

I shall be getting a spark to do all the wiring as i really dont fancy putting myself or my house up in smoke

 

[Steve]

I am just interested in learning about the subject as like to know how things work

Nowt wrong with that.

Like I said, get a length of 10mm² and run it, taking photos of the depth or burial for the electrician to see, so he can sign it off as compliant. Leave a couple of feet slack either end for connection.

 

[ban-all-sheds]

I have asked for some advice and would like to learn something along the way to make sure i dont get ripped off

You have absolutely no intention of using an electrician, do you.

 

[Steve]

give it a rest ban.

 

[ban-all-sheds]

Do you think he does?

 

[Steve]

Do you think he does?

I dont care! If he wants my advice he can have it. If I think he hasnt a clue, I will tell him as such and stop my advice.

 

[ban-all-sheds]

That's fair enough, but from where we're standing, the sort of questions your asking make it look like you plan to attempt this work yourself, and there is in fact no electrician involved at all. If you don't plan to carry out the work then there really is no need for you to be able to calculate cable sizes.

If you intend on doing the work yourself then you would have got a far more favourable response by being upfront and honest about it.

Precisely.

But Steve doesn't mind being insulted, so.....

 

[jackofnotrade]

I have asked for some advice and would like to learn something along the way to make sure i dont get ripped off

You have absolutely no intention of using an electrician, do you.

sorry do i know you?

You have no idea what i do or do not intend to do. If you have no helpfull information or worthwhile input go and type else where

thanks