twin and earth between block wall and dot dab - cable channels needed?

[Deuce]

Hi all,

Our sparky has carried out first fix, twin and earth cables clipped to the block walls of our extension routed to each back box. His leaving instruction was to dot n dab the plasterboard over the cables - but he has laid them without plastic or steel cable channels and in such a manner that I'd have to re-route many of them to fit within channels.

Is it actually a requirement to use channels or is it fine to just put the plasterboard directly over the cables? I'm obviously thinking it's going to make it very easy for someone in the future to have a 'shocking' experience putting up shelves.. but much as I google the question I see many suggesting no protection or plastic channels - which of course a drill bit would shoot through anyway. I personally use a detector but I guess most do not.

What do the regs say about this? Elsewhere in the house I have found steel channels used, I can see the sense in them but in this instance, using them would pretty much require starting again.

Thanks in advance for any help.

 

[cliffed]

Find it easier to use metal channeling it keeps the cables in place…but like all have said nothing wrong in not using it…obviously all cabling will be protected by rcd/rcbo’s

 

[7029 dave]

We normally fit metal capping or oval tube, its just if you do have damage you have some chance to pull through, but only sparks seem to be aware of 150mm from ceiling, .. i personally think he is so booked up, they just tacked the ceiling,
I dont no any sparks would wire like that when they could have gone through joists.

I did exactly that when converting my integral garage. Above was the third bedroom all laminated floor did not want to pull that up.
All services were in the garage so it weren't too bad, just quite a bit of chasing 150mm from ceiling all by hand most of it was internal block work. External wall was hard brick an rendered.

 

[Deuce]

*where the wall thickness is <=100mm

Thanks, good to know the regs, although - as below...

This is where it gets a bit silly IMO, you just cant avoid these situations, to keep compliant chop in a shallow box and blanking plate there is your prescribed zone, but who's going to want that.
Just having a moan Daz off the beer trying to lose some timber. lol

That was what I thought when this thread first educated me about the zone being created only when there is an obvious fixture for the cables to be routed towards. I must have seen hundreds of exterior lights that can only be supplied by cables run in this way but no one is putting a blanked off box on the inside of the wall.... Has anyone ever seen this actually done? I can imagine a very particular spark perhaps suggesting such a thing, but I can't imagine their home owner customer liking the idea!

Sorry you're off the beer by the way. Sounds none compliant to me!

 

[Deuce]

Find it easier to use metal channeling it keeps the cables in place…but like all have said nothing wrong in not using it…obviously all cabling will be protected by rcd/rcbo’s

I have drilled through a live before. Big bang and a moment of confusion - but yes, the circuit was de-energised instantly. I have since used a detector, they may be crap at accurately locating studs and pipes but they're very good at detecting a live cable.

On reflection, using boxes to define zones based on the theory it will give future diy'ers a vague clue as to where the cables are probably puts people off bothering to use a detector to make certain - which I believe they should. Not because there is much chance of a serious shock, but because there is a very great chance of falling off a step ladder, stumbling, dropping your drill or soiling yourself when it happens..