Outside Electrical Point

[sotv]

Anybody any experience of this?. i am thinking of getting a suitable Electrical Socket and Cable installed up the garden for my smoker (maybe some outside lighting up there as well, still undecided on that), it will be about 20-25 meters from the fuse box and hoping to get it done at the same time as when we have some new fencing put up later this year . Will I require certification from anyone from electrical or building after I have had the work completed, or would there be no need?

[Justin]

You will need an electrician mate.  Outside plug is like a outside light. I have one that spurs of a power point inside and for reason on the fuseboard that power point. This is fine for a light. It  depends on the load. For example my garage power spurs off a power point to a separate sideboard because I have a higher load in there with fridges lights and a dehumidifier plus sometimes a drill. And my homebrew kit. Plus I am going to eventually put a heater in there...  

Once done it is very useful.

 

You could use an extension cable of course. Much cheaper.

[Wade]

Is this going to be totally outside or is it close to a shed or outbuilding?

When I laid power and  data to my smokery and workshop, following the advice of a local electrician, I used armoured cable clipped to a pressure treated board at the base of the fence. Using armoured cable protects against accidental damage from gardening equipment and also from animals. 

If you have a shed at the other end then it would be a good idea to fit a second RCD unit so that if something in the garden causes a trip then it is less likely to affect the rest of the house and would be easy to troubleshoot. The second RCD then goes to your external sockets.

If you dont have a shed then simply terminate the cable with a double (or more) external weatherproof socket that has its own built in breaker.

Instead of the armoured cable you could use armoured flex (SY cable). This is more flexible to install but would tend to sag more between clips.

https://www.armouredcable.net/armoured-cable/4mm-armoured-cable.html

https://www.armouredcable.net/4mm-3-core-sy-cable.html

With cable lengths of this distance you need to ensure that you select the right size cable to take into account the voltage drop. To calculate the minimum size cable you need there is a handy calculator here https://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html. Do not spec to your exact requirements - it is always best to use the next size cable up in case you use it for power tools or electic patio heating etc. in the future.
I am not sure if the 25 metres takes into accound the cable run inside the house to get it to the existing consumer unit. I have assumed not, and have increased the actual required cable length in the calculation to 30 metres. Using the calculator the maximum loading on a 2.5 mm* cable would be 4 Kw - however on a 4 mm* cable you could go up to 8 Kw. The difference in cost is not that great and, personally, I would go for the higher spec.

* cable size refers to the cross sectional area of the cable and not its diameter.

[Raptor72]

I’ve got similar setup to wade 

definitely need armour cable and Additional RCD box at the end point 

Edited January 19, 2020 by Raptor72

[Justin]

From power point near front of house.

 

Then along fence a long way.

And eventually across garden to outside garage.

Then inside is sideboard to 8 sockets and three led light strips.

[sotv]

Thanks for the replies, useful information. It will be just for a pellet grill and maybe one of those Philips Hue Outdoor Lights attached to the fence , nothing more. So hopefully a double weatherproof extension socket will suffice. But if possible to spur some extra Philips lighting from the cable for the patio closer to the house.

With new fence going in hopefully get the work done together. Only problem fusebox is on the other side of the house to the garden and a lot of difficulties to hide cable from there to get it outside, so it may prove too difficult for that to come to fruition with that method, will see if electrician can work round it and perhaps do something from one of the existing power points in the kitchen?. I will get armour cable. it is the possible need for certification of any works that are troubling me as it appears to be needed but most people seem to ignore it. I am sure an electrician will advise me anyway. 

[sotv]

Booked an electrician to fit one in the next 10-14 days, costing me a new fusebox as well, as the current one is over 40 years old and a cassette type, but it  needs doing for the house in general as well and means I  can now have an outside weatherproof double socket safely spurred off the socket in the kitchen to run the cable outside from it and the new fusebox means it will be able to be isolated if it ends up tripping for any reason.

So hopefully that will be the end of needing to run an extension cable outside the kitchen window to run the smoker now.

[sotv]

Went with a single one in the end as a second socket not really needed now and as it was best secured to the fence itself rather than the concrete post. Glad I got an electrician and the fencers were here at the same time to do it as a groove had to be cut into and along a slab and the rounding of a corner so the armour cable could run from the external wall along the edge of the patio to the fence, and wasn't bent at a sharp 90 degree angle at any time. 

Not sure how true it is, but buried mine under stone chippings along the edge of patio and fence , as advised covering it in concrete is corrosive to the casing, long term. No interruptions to cooking with the grill now, due to wet weather now hopefully 😀

 

Edited May 13, 2020 by sotv