External cable

[Sunshine12]

hi, looking to run some cable down the garden before we turf/landscape next week. Already have an outdoor socket & was told by previous electrician could spur off that in the future.

What cable would be required for both power & lights? (eg shed/outdoor lighting) eg what core & mm?

I’m only planning to lay it at the moment not actually have it connected up. Can’t get hold of the electrician. Will use safety tape. Is ducting necessary with armoured cable?

Ta

 

[Tigercubrider]

the electrician needs to see what you've done - or at least approve it .
If you can't contact him, wait.
I'd use a duct as it's easier to replace the cable or add something.

 

[Sunshine12]

He told me how to lay it in the borders, How deep, where to & from. He just didn’t tell me what core cable. All I remember him saying is make sure it is for both power & lights, not just lights.

 

[Notch7]

He told me how to lay it in the borders, How deep, where to & from. He just didn’t tell me what core cable. All I remember him saying is make sure it is for both power & lights, not just lights.

it could be any size and any number of cores depending on use and length. I would get the electrician to confirm even if you have to wait.

 

[winston1]

3 core SWA. Size depends on loading and length. 2.5mm is probably OK for small power tools and some lights for the avarage garden length.

 

[ban-all-sheds]

Sunshine - you should PM Winston, as you need to get his contact details as you've got to get him to sign this declaration on an EIC:

I being the person responsible for the design of the electrical installation (as indicated by my signature below), particulars of which are described above, having exercised reasonable skill and care when carrying out the design hereby CERTIFY that the said work for which I have been responsible is to the best of my knowledge and belief in accordance with BS 7671:2008, amended to 2015 except for the departures, if any, detailed as follows:​

You also need him to put some sort of warranty in place to cover the costs of replacing the cable if it turns out not to be large enough.

 

[Blueflash]

See you on Tuesday Bas ?

Kind regards,

Dave

 

[Sunshine12]

Thank you Winston. Electrician has just text to say 3 core 2.5mm!

 

[JohnW2]

Thank you Winston. Electrician has just text to say 3 core 2.5mm!

For what it's worth, and particularly since you're about to have landscaping done, I would personally either put in a duct or else use SWA appreciably larger than 2.5mm² - since it's amazing how many people come fairly soon to think of a reason why the need significantly more electricity in their garden/shed/whatever than they originally thought would ever be needed!

Kind Regards, John

 

[DetlefSchmitz]

See you on Tuesday Bas ?

Not sure what this person has to do with the thread - but he doesn't seem able to spell.

 

[Sunshine12]

For what it's worth, and particularly since you're about to have landscaping done, I would personally either put in a duct or else use SWA appreciably larger than 2.5mm² - since it's amazing how many people come fairly soon to think of a reason why the need significantly more electricity in their garden/shed/whatever than they originally thought would ever be needed!

Kind Regards, John

Thank you John, that is a good point. He told me to run one for each eg a 3 core swa 2.5mm for lights, then the same again for power.

I’d rather use swa, it’s a long garden & that ducting isn’t cheap is it?!

 

[JohnW2]

Thank you John, that is a good point. He told me to run one for each eg a 3 core swa 2.5mm for lights, then the same again for power.

That's a fairly unusual way to do it

I’d rather use swa, it’s a long garden & that ducting isn’t cheap is it?!

I wasn't really suggesting that you shouldn't use SWA, but rather that the SWA could be put in a dict so that it could be replaced with larger if that ever became necessary, without having to destroy your beautiful garden.

It's a long time since I bought any, but in the context of the price of SWA and, more particularly, the cost of landscaping. I think that the marginal cost resulting from putting SWA into ducting would be relatively minor.

Others might even suggest that you should put in two ducts - one for such things as telephone and other communications (i.e. ethernet) and alarms etc. purposes, should you ever decide you need them.

Kind Regards, John

 

[Sunshine12]

Ok, fair point. I think because it’s not going to be connected up/used for probably a long time it’s hard to spend hundreds on ducting & cable, as well as all the expense of landscaping. But appreciate I need to now to do it now to avoid ruining the garden.

Think I’ll have to just lay the duct & string for now then after all. I’ve asked him why 2 cables, he said because otherwise it will be only be possible to have lights at the same time as power & vice Versa. So to have power we would have the lights on too. He fitted an outdoor socket last year for us (double) & will spur off that as & when the time comes. Clearly I’m not an electrician. I just want to lay the ‘best’ option for future uses. He told me 700mm down, with warning tape 3-400mm down. It will be the landscapers actually laying it once everywhere has been dug out & levelled. I have the electrical wholesale book ready to order the swa but having question marks now

 

[JohnW2]

Ok, fair point. I think because it’s not going to be connected up/used for probably a long time it’s hard to spend hundreds on ducting & cable, as well as all the expense of landscaping. But appreciate I need to now to do it now to avoid ruining the garden. ... Think I’ll have to just lay the duct & string for now then after all.

Fair enough - that would certainly keep your options open, and protect your investment in the landscaping. Others here can probably advise you what sort of ducting would be best.

I’ve asked him why 2 cables, he said because otherwise it will be only be possible to have lights at the same time as power & vice Versa. So to have power we would have the lights on too.

If he really said that, it's nonsense - there will surely be a light switch which you could use to switch off the lights if you only wanted power?!

He told me 700mm down, with warning tape 3-400mm down.

I would think that would be more than adequate.

Kind Regards, John

 

[ban-all-sheds]

Ok, fair point. I think because it’s not going to be connected up/used for probably a long time it’s hard to spend hundreds on ducting & cable

Hundreds?

How long is the garden?

I’ve asked him why 2 cables, he said because otherwise it will be only be possible to have lights at the same time as power & vice Versa.

True, if you want to be able to switch the lights on from the house end.

4-core cable is an alternative. Or 5, if you think you might want two sets of lights, or lights and a water feature pump.