Should I use conduit for cables in the service void

[MikeSharp01]

Just been doing first fix electrics in the garden room and I am wondering if I should thread some conduit in around the drops to the sockets for the light switches, ring main and the network cables that run in the service void. You can see the drops in the photo. The wires will be 37mm back from the face of the plasterboard as they run behind the horizontal battens and if I use 30mm plasterboard screws that will be OK and given that they run vertically down to the sockets they should be in a safe zone. All the same I thought I would elicit opinions.

[Onoff]

You know safe zones are 150mm from the ceiling, internal corners and then in line horizontally or vertically of sockets, switches?

 

That cable on the lhs wall up by the roof then looks low.

 

Nothing to stop you running horizontal between sockets down low.

 

I'd run in conduit. You could even use singles if it took your fancy.

 

EDIT: Are you using the "50mm" rule to put the cables deeper than the zones? There's always someone who'll put a longer screw in!

Edited August 23, 2017 by Onoff

[ProDave]

+1 to running horizontally from socket to socket. I had a stand up finger wagging argument last year with the joiner building a house I was wiring, he was trying to tell me you can't do that and must take the cables up above the ceiling across and back down again

 

And yes that left hand run looks to be more than 150mm down from the ceiling.

[Onoff]

Tbh I've always thought running cable in the 150mm zone either side of an internal corner is bloody silly. It's the first place Joe Public puts shelf brackets. Keep everything in line with switches and sockets and you won't go far wrong. For that matter, 150mm down from a ceiling.....how many people have just banged a quick nail or two in to hold up coving whilst it's setting?

[ProDave]

My only gripe is nobody else apart from electricians knows about safe zones.

 

I am not convinced they are entirely well thought out. I have seen it before, someone wants to hang a picture on a wall. There is a socket below it. So to make it "look right" out comes the tape measure to ensure the picture is exactly centred on the location of the socket........

[Onoff]

6 minutes ago, ProDave said:

My only gripe is nobody else apart from electricians knows about safe zones.

 

I am not convinced they are entirely well thought out. I have seen it before, someone wants to hang a picture on a wall. There is a socket below it. So to make it "look right" out comes the tape measure to ensure the picture is exactly centred on the location of the socket........

 

Agree in spades! That's why I'm such a fan of galv conduit. This was mid new kitchen. The place came with a nice dinner gong...I just knew so carefully excavated to show this:

 

 

 

 

 

A near miss methinks!

[jack]

I found some galvanised conduit behind a rendered wall once, long before I knew about safe zones. I'm pleased it was there, because if it hadn't been I'd have gone straight through the wire!

[MikeSharp01]

10 hours ago, Onoff said:

That cable on the lhs wall up by the roof then looks low.

 

10 hours ago, ProDave said:

And yes that left hand run looks to be more than 150mm down from the ceiling.

I agree it looks low but the ceiling in that area actually comes down onto the upper batten and after the thickness of the PB is taken into account the base of the slot is 130mm below the finished ceiling so should be OK even allowing for 'droop' between the battens. The VCL is 62mm back from the finished face of the wall so cables resting on it or, I guess, taped to it would be 50mm back, If I put them in conduit they won't but I guess that will be OK as they will be protected.

 

Much thanks all, perhaps will get some conduit - see below.

 

9 hours ago, ProDave said:

I am not convinced they are entirely well thought out. I have seen it before, someone wants to hang a picture on a wall. There is a socket below it. So to make it "look right" out comes the tape measure to ensure the picture is exactly centred on the location of the socket........

You guys already helped me out with the safe zones on the gable wall and I have been using the document at these links https://www.diynot.com/wiki/Electrics:walls and http://electrical.theiet.org/wiring-matters/54/cables-in-walls/index.cfm for my work although the second one is perhaps wrong in showing all the zones as the same when the drops from / horizontal runs between sockets need to be 50mm back or mechnically protected I believe and that one is from the IET although I am led to conclude that provided the circuit is RCD protected you do not need mechanical protection which is the path I was taking, not sure any more!

Edited August 24, 2017 by MikeSharp01
Sense change of thanks.

[ProDave]

They don't "need" to be 50mm back, it's just that if they are less than 50mm, the circuit must be protected by an rcd.

[MikeSharp01]

1 hour ago, ProDave said:

They don't "need" to be 50mm back, it's just that if they are less than 50mm, the circuit must be protected by an rcd.

Ok, so, IF in a designated safe zone AND less than 50mm back AND protected by an RCD then mechanical protection NOT required. (specialized case) Is that correct it seems to be what the regs say if I read them right in light of this conversation.