What size cable to run from house to garage?

[Williamraff]

Hi folks, I don't currently have a garage but I am in the process of building one. I will be digging a trench to bury armored cable this weekend and just wanted to know what size spec would be recommended?
I intend to use the garage as a workshop and will be running a compressor, welder, lights sockets etc on a regular basis.
I am happy to over spec if required and will be using a NICEIC electrician to do the wiring in to the house and the garage.
I have not approached Building control as yet, am I right in thinking that I should?
Many thanks,Will.

 

[PrenticeBoyofDerry]

Hi folks, I don't currently have a garage but I am in the process of building one. I will be digging a trench to bury armored cable this weekend and just wanted to know what size spec would be recommended?
I intend to use the garage as a workshop and will be running a compressor, welder, lights sockets etc on a regular basis.

You would require the output demand of the electrical equipment and the cable distance that garage would be from house consumer unit.

I am happy to over spec if required and will be using a NICEIC electrician to do the wiring in to the house and the garage.

There are more than just NICEIC electricians available!
http://www.competentperson.co.uk/

I have not approached Building control as yet, am I right in thinking that I should?

That would depend on whether you employ an electrician that can self cert/notify the work for you, but as you have not yet got an electrician on board, you should be notifying and getting approval prior to you starting this work.

 

[Williamraff]

Hi folks, I don't currently have a garage but I am in the process of building one. I will be digging a trench to bury armored cable this weekend and just wanted to know what size spec would be recommended?
I intend to use the garage as a workshop and will be running a compressor, welder, lights sockets etc on a regular basis.

You would require the output demand of the electrical equipment and the cable distance that garage would be from house consumer unit.

I am happy to over spec if required and will be using a NICEIC electrician to do the wiring in to the house and the garage.

There are more than just NICEIC electricians available!
http://www.competentperson.co.uk/

I have not approached Building control as yet, am I right in thinking that I should?

That would depend on whether you employ an electrician that can self cert/notify the work for you, but as you have not yet got an electrician on board and you should be notifying and getting approval prior to you starting this work.

Many thanks for the response, I was not aware of the competent person scheme.
Will.

 

[Robin0577]

Your best move if you want to get on with the groundworks straight away would be to bury a duct with a rope in it so the cable decision can be left to the sparks.

3"/75mm twinwall corrugated duct ducting should do the job, something like this http://www.draindepot.co.uk/index.asp?u=107&m=&cat=3&scat=13&t=Duct+Systems

Keep bends to a minimum and as gentle as possible, place warning tape over the top and take photos before filling the trench in so that the sparks can verify the (s)he's happy with it.

While you're at it a second, smaller duct alongside for phone/data cables in the future wouldn't be a bad move.

 

[Aragorn84]

Make sure you stick a decent size in.

I'll probably be running a 10mm cable to mine.

Better to spend the extra now and run a big cable, than to stick a 4 or 6mm in then discover later that you really want a bit more power. The extra cost is small compared to the cost of the whole project, and when compared to the cost of digging it up again!

 

[mikeyd]

Wrong reply, please delete.

 

[PrenticeBoyofDerry]

Many thanks for the response, I was not aware of the competent person scheme.

There are quite a few scheme providers these days, all the members can notify for you, can often be worth employing just for the reduction in notification fees.
If you input your location a list of electricians that are deemed competent will appear.
You could also check out here:
http://www.electricalsafetyregister.com/
and
http://www.electricsaferegister.co.uk/

 

[Williamraff]

Your best move if you want to get on with the groundworks straight away would be to bury a duct with a rope in it so the cable decision can be left to the sparks.

3"/75mm twinwall corrugated duct ducting should do the job, something like this http://www.draindepot.co.uk/index.asp?u=107&m=&cat=3&scat=13&t=Duct+Systems

Keep bends to a minimum and as gentle as possible, place warning tape over the top and take photos before filling the trench in so that the sparks can verify the (s)he's happy with it.

While you're at it a second, smaller duct alongside for phone/data cables in the future wouldn't be a bad move.

Thanks, ducting it is then.

 

[Williamraff]

Make sure you stick a decent size in.

I'll probably be running a 10mm cable to mine.

Better to spend the extra now and run a big cable, than to stick a 4 or 6mm in then discover later that you really want a bit more power. The extra cost is small compared to the cost of the whole project, and when compared to the cost of digging it up again!

Yes, I would rather over specify than under.

 

[Williamraff]

Many thanks for the response, I was not aware of the competent person scheme.

There are quite a few scheme providers these days, all the members can notify for you, can often be worth employing just for the reduction in notification fees.
If you input your location a list of electricians that are deemed competent will appear.
You could also check out here:
http://www.electricalsafetyregister.com/
and
http://www.electricsaferegister.co.uk/[/QUOTE]

Thanks, I will have a look at some in my area.

 

[PrenticeBoyofDerry]

If you get one on board they will help you calculate the cables size required for both load demand and voltage drop.
If you wish to do the donkey work, it may be possible that electrician will be happy to make final connections, certification and notification for you providing they see all cables prior to them being buried/hidden.
It could end up saving you quite a hefty notification fee!