A few questions on new wiring Ask questions and find answers to many subjects relating to electrics and electrical work

[JockeyB]

Hello. I'm new to submitting something on this forum but had already used some of the advise on it. I'm now after some help/advise please on a few wiring issues I'm having.

1: I'm putting a 2 way lighting system into a utility room (using 1mm T&E & 1mm 3core & E). I thought I could run T&E from the CU to the first ceiling rose, connect all additional lights from that first rose and run live feed from said rose down to first switch. Then connect the 2 switches using the 3 core & E. However, most diagrams I've found show live feed from CU going through a JB. Are both ways correct? Is the JB method used if I wanted to run another light circuit from the same CU MCB?

2: Can I run plastic 20mm conduit in Celotex and then screed over it?

3: Can I still use plastic capping on block work (to be plastered over)?

Think that will do........for now. Look forward to receiving replies.

Jockey

[kbrownie]

Hi Jockey,
What you suggesting to do sounds like a good logical method of installation.
BUT! and there always is one, if you have been reading some of the recent post on this forum.
You will notice that document p of the building regulation pops up a lot, I advise you to have a look in project pages on part p.
As you are installing the lighting circuit from the CU it automatically becomes a new circuit and under regulation should have an EIC (Electrical Installation Certificate) which will also require schedules of inspection and testing, this will prove it conforms to BS7671:2008 which it must do!
Regards
KB

[JockeyB]

Hello KB,
Thanks for the Projects/Part P heads up. I had a quick look but didn't see anything about the plastic conduit under screed or plastic capping in there. Do you know if both of those are acceptable?

Regarding Part P & 17th Edition : I've got either a qualified spark who's going to check my work during it's completion (as I'm running a ring main to extension both ground & 1st floor too) then test, inspect & certificate it for me OR I'm going to contact local council building regs and ask them about doing that. Would rather it be the former option though as I've heard the council charge quite a lot.

Thanks for your advice.
Jockey

[kbrownie]

Hi JockeyB,
Plastic conduit/capping can be used to protect cable from plasterers trowel. Conduit will offer ease of re-wire in future.
Recommend using RCD/RCBO on circuit as BS7671:2008 requirements.
KB

[kbrownie]

I should have mentioned that cable can be run in permitted zones but if not must be burried 50mm in to wall or have mechanical protection.
KB