10mm SWA questions

[Seanl]

Afternoon all, newb here and I have a couple of questions regarding wiring to a garden building. I've had a good search online but can't find any definitive answers or anything similar to my circumstances recently. So the background is I have 10mm SWA that I need to run to a garden building. It's approx 26m from the CU in the house, going to an IP rated sub main CU in the workshop. It's only supplying lights and a couple of sockets initially, but I want to future proof as we've been considering a hot tub for a while, so a 32a supply will give us greater options. The first question related to entering the property. The house is a period one with foot thick stone walls. The main CU is in the front room and you can see on the pic the mains in cable to the CU. Drilling through from internally to ensure I miss any other cables is obviously the wisest choice, but a 25mm hole through such a thick wall isn't my idea of fun. Coupled with the bend radius externally and the preference for neatness, would a terminal box be advisable in this situation and if so, does anyone have a link for an appropriate one? The cable would then be run along the side of the house for approx 3m at 2m height, down and underneath patio slabs on a step, then through a block wall which acts as a flower border. The second question I have is routing. The flower border runs parallel to a fence which rises up, so the only suitable route without raising the rear patio (not really an option as it's recessed so slabs will have to be broken to lift) is to run it along that border. Given that it's right next to the fence, if the posts needed to be replaced then that's the only place to dig. Being 2 -2.5 foot deep as they are, burying the cable would present more of a risk of it being damaged even with warning tape in place. I've seen previously that others have located the cable behind gravel boards. Is this something that those with experience would recommend in this situation as well? Sorry for the long post, I've tried to add photos for clarity but can't seem to attach them at the moment. Any advice would be very much appreciated. Thanks, Sean.

 

[Murdoch]

Your own place ?

 

[Seanl]

Your own place ?

Yes

 

[Evans Electric]

Its difficult Seanl  as we can't see the job .   What exactly is worrying you ?     The cable may be damaged in the future by a fencing guy  ?  

Trouble is , none of us would ever get anything done if we went on that way .        Basically , bury it in the ground about 18 inches deep  , half fill , lay warning tape. 

My last three garage supplies  were done  by glueing 25mm PVC saddles to gravel boards  ( You shouldn't drill them)  a day before starting job.    Feed sections of conduit down cable & fix in place .        I've seen cable fixed to fence panels  but its not the best idea .      Glue saddles with  a mastic  C10  I think we used.  

 

[Murdoch]

Yes

Then you need to consult a local spark ..... before you start.

 

[Seanl]

Its difficult Seanl  as we can't see the job .   What exactly is worrying you ?     The cable may be damaged in the future by a fencing guy  ?  

Trouble is , none of us would ever get anything done if we went on that way .        Basically , bury it in the ground about 18 inches deep  , half fill , lay warning tape. 

My last three garage supplies  were done  by glueing 25mm PVC saddles to gravel boards  ( You shouldn't drill them)  a day before starting job.    Feed sections of conduit down cable & fix in place .        I've seen cable fixed to fence panels  but its not the best idea .      Glue saddles with  a mastic  C10  I think we used.  

Thanks for the reply. Yeah the fact that it's more likely to be damaged by burying than fixing to the gravel boards - they're wooden if that makes any difference. The fence follows all the way to the garden building, and has a flower border next to it all the way up with a border wall about 8" in from that for the first half of the run. It could be buried next to the fence with the potential for damage, then it would have to cross the flower bed and run up the lawn before crossing back to the fence and into the building which butts up to the fence at the end of the garden. It seems a very convaluted way to run it though. I want to do it properly, but It just seem the least likely route to cause damage would be behind the gravel boards. I'm in a rural location too so getting a local spark to assess isn't easy as they're all so reluctant to travel to me.

 

[Seanl]

Of house, from mains CU at second window, along to edge by gate, then down under fst step slabs

 

[Seanl]

I can't add the remaining pics as they're too large, but in the second one, you can see the border wall next to the fence and how it rises. It goes to about 4 feet high then levels off where the main part of the lawn is. The main part has a flower border next to the fence and follows all the way back to the building where it needs to go. Hope this clarifies a bit better than my original description! 

 

[Murdoch]

. I'm in a rural location too so getting a local spark to assess isn't easy as they're all so reluctant to travel to me.

That’s no excuse not to follow the electrical and building regs.

just saying

PS give it a couple of weeks and I suspect they will be extremely happy to travel

 

[binky]

North Devon is all rural  :lol: . If you were in South Devon I would happily pop out to have a look. 

 

[Andy™]

id take a look but the callout fee wouldnt be cheap