Pulling Cables through Ceiling Void

[Conor]

Hi, a few parts to this!

 

I need to bring a 6mm2 cable across from the consumer unit to opposite side of the house though the basement ceiling void to wire up an EV Charger. Was originally meant to be on the same side of the house as the consumer unit but, alas, things change. Consumer unit is prepped for the charger wiring, and the charger itself only needs the three core cable.

 

The ceiling is all boarded up, so I want to minimise entry into the voids. 

 

The image below shows the locations, and the red line is the route I plan to take. There is an existing cable tray and I hope to get the cable in it (bonus). The walls are cored out where the trays pass through.

 

Yellow squares are where I think I need cut into the ceiling to be able to push/pull through.

 

Ceiling is suspended with about 150mm total space.

 

I'll drill through the external wall from the outside, and hopefully be able to hook on to the cable and pull through.

 

Really want to minimise opening and not have any in the hallway.

 

Total cable length ~13m.

 

Is this feasible? Any tips using a fibreglass rod? And Do i try and pull the wire itself or a draw cord first?

 

Thanks

 

Edited Wednesday at 14:10 by Conor

[BotusBuild]

Conor, 

I would try to pull a drawstring through first - hit, and overcome, all the snags and route smoothly without possible damage to the 6mm cable.

I think you would benefit from a hole at the wall where the cable goes the wall to the charger to make feeding the cable as easy as possible.

I have used a piece of wire taken from a stock fence to do similar routing instead of the fibreglass rods. You can bend it when necessary to go over or under awkward points.

Also, when you start pulling the cable with the drawstring, have someone feeding the cable in the first hole to reduce tension in the string and the cable. This also minimises damage to the outer insulation.

Good gaffer or duct tape is very useful for this job.

Best of luck with this.

[SteamyTea]

I worked with an electrician and he had a very long, flexible, coiled steel spring, with a light at the end.

Was a simple bit of kit but made pulling cables through easy.

No idea where he got it from, or if it has a name. 

 

[Conor]

Did this today.... Went as expected, tho I needed an extra hole in the ceiling in the hallway. Fiddly and uncomfortable job. Hopefully first and last time!!

[Conor]

Well, charger is up and running. About 8hours work in total, with plenty of faff on my belhalf. Can't figure out why the spark was looking £600 labour only.

[Alan Ambrose]

Congrats - any tips you can pass on?

[Conor]

Yes, 5mm poles are too flexible for going through a ceiling void horizontal. Max 2-3m before the tip drops down and gets snagged on the ceiling bars / insulation. I'd get 8mm if doing it again.

 

And drawstring didn't work. Cable kept getting snagged. Better way was to attach the cable directly to the rod with tape.

 

Installing the charger itself was easy. Project EV Apex 7. It's literally one cable, three connections each end. My consumer unit already had a 32amp RCBO installed with common neutral for the charger, so was just a matter of pulling the cable in and wiring it up.

 

The Apex 7 doesn't need it's own earth, has lots of built in fault detection functions, so I'm confident it's all as should be and safe.

 

Main motivation of doing DIY was not money, but time. We bought the car last Monday, only way to charger is at public fast chargers at ~65p/kWh. Couldn't get an electrician round any time soon.

Edited 13 hours ago by Conor

[BotusBuild]

10 hours ago, Conor said:

And drawstring didn't work

Sorry (sheepish grin)