Running cable into house from meter

[jake123]

Hi All,

 

New member here, looking for a bit of advice, sorry if it's a trivial question!

 

I'm looking to convert my garage to a kitchen, it's an integrated garage which is at the far other side of the house to the existing consumer unit. After discussing with the electrician, we agreed it would be simpler to split the power coming in to the meter into two due to the strange layout of my house: one to existing consumer unit then a second (new one) to run to the new kitchen. This all sounds reasonable to me so far (keen to hear if others disagree).

 

The question I have is, to save money we agreed I would dig the trench and run the ducting into the new kitchen (about 5m). So I've gone ahead and purchased a roll of 63/52mm twin walled underground ducting and was going to run that. Now to the second question: if I run this underground, how do I get it into the house? Would you normally bore a hole the size of the ducting and run the ducting through the wall into the room (going through the floor isn't an option). Or do you terminate the ducting/cable to some sort of junction box that then runs through the wall to the inside of the house (assuming this would be underground unless you come up to then go through the wall).

 

Thanks in advance for any thoughts and tips!

 

Jake.

 

[Nickfromwales]

Hi Jake.

Yes, your electricians proposal sounds a practical one tbh. Without plans and an some understanding of the topology we cannot really argue either way though  

Basically you'd usually use a drill bit to drill a series of holes into the slab ( called "stitching" ), missing the foundations, and then chisel out the core to get the duct in to floor level. If it was a steel wire armoured cable, you really don't need the duct as that type of cable is suitable for 'direct burial' but a duct is belt and braces and favoured by many. If you cannot get through the slab ( so you are trenching outside, yes? ) then you ca just stop the duct at ground level, then clip the steel wire armoured cable up the outside wall and then just drill a hole that size to get you inside the house again. Drill uphill, from outside in, when you drill the hole to stave off ingress of rainwater  

[jake123]

Really helpful thanks so much Nick!

 

I am indeed trenching outside at 450mm. Running the cable only through the wall and leaving the ducting at ground level feels much easier - not so keen on making a 63mm hole in the wall if that's an option  What do you close the ducting off with, some sort of grommet?

 

 

Cheers,

Jake.

[jake123]

Also - was looking at 16mm2 armoured cable such as this: Prysmian 6943X Black 3-Core 16mm² Armoured Cable 25m Drum | Cable | Screwfix.com

 

Does that seem suitable? My electrician is impossible to get hold of otherwise I'd ask him to spec it..

[markc]

16mm SWA is more than sufficient for this purpose. Close the duct off with some insulation or squirty foam. Also drill your hole though the wall slightly downhill towards the outside to prevent water creeping along the cable and into the house.

[jake123]

Thanks for the help Mark! ?