Trunking

[unlucky]

Just had a quick search and couldn't find anything relating to this. Go easy if its an obvious question but if I don't ask I will never know the best way to do it!!

Right, now the excuses are out of the way... I've been reading around the 17th ed regs and part p and can't find anything about locating the wires in chases (i.e. to switches and sockets) in trunking but was wanting to know what best and accepted practice is? The chases I'm referring to will be located in safe zones, so no need to provide protection from a safety point of view and that which isn't will be protected with capping.

Would it be nicer for the next person who re-wires to put trunking in all the chases so they don't have to chase the walls ever again or is this a bit over the top?

Thanks and apologies if its already been answered.

 

[Taylortwocities]

Put capping over if you want to. If the cables are in the proper zones then there is no reg to say you must.

Capping does not allow you to go outside safe zones in any case, its only there to protect the cable from the demon plasterer and (as you say) to make things easier for the next bloke.

 

[holmslaw]

..

 

[GaryMo]

No, it's not over the top.
Many people use oval conduit for that very purpose.

 

[Spark123]

Capping or oval conduit is different to trunking - you would normally install trunking on the surface and avoid the concealed cable requirements (safe zones) in doing so. Not very aesthetically pleasing but where aesthetics don't matter it is a good thing.

 

[unlucky]

Cheers for the quick replies.

I'll probably use oval conduit seen as though all the walls are going to be back to the plaster for re-skimming with all the chases cut out. Seems a tad lazy to have the cables plastered in and slightly awkward for the next person that re-wires, although that will be in a fair few years.

Another question then...

I thought that running the upstairs ring and lighting inside capping would avoid the need to place it in a safe zone?

Its not really an immediate concern as I'll probably make these runs in a corner of the kitchen inside the corner safe zone, just interested.

Thanks again.

Phil

 

[Taylortwocities]

To go outside safe zones the cables must be either

More than 50mm from the surface
or
run in earthed steel conduit
or
must be cables that comply with special requirments (eg armoured cables, etc)

Plastic or galvanised metal capping/ conduit does not comply.

Be careful about the corners of kitchens. Kitchen fitters often hang cupboards on the walls there, and they dont know or care about safe zones for cables.

 

[flameport]

Seems a tad lazy to have the cables plastered in and slightly awkward for the next person that re-wires

Perhaps, however as the rewire will inevitably mean accessories in completely different places, and could well mean completely different types of wiring, this is not an issue.

It's the same situation as if you have wiring from the 1960s today - the fact it is in conduit or whatever is largely irrelevant, since far more socket outlets are required and lighting probably isn't a single lamp hanging down from the ceiling.

 

[unlucky]

Thanks for the warning, Its my dad and me that will be fitting the kitchen so no risk (i hope) there!!

Its also not in a place that you would place a cupboard, its a walk way through to the extension, if it had one there you couldn't get to the washing machine.

"To go outside safe zones the cables must be either

More than 50mm from the surface
or
run in earthed steel conduit
or
must be cables that comply with special requirments (eg armoured cables, etc)"

Thats what I thought, however I've just taken a load of tiles off the wall I am planning on using for the aforementioned cable runs and found, outside of the recomended safe zone I was planning on using, some steel capping with the 6mm shower circuit running inside it, I uncovered this with a SDS chisel, good job I had switched it off as I thought thats where it was!!

That was fit by the council as part of a bathroom for the previous owner (disabled shower etc). Just goes to show!

Thanks as always.

[/quote]

 

[unlucky]

Seems a tad lazy to have the cables plastered in and slightly awkward for the next person that re-wires

Perhaps, however as the rewire will inevitably mean accessories in completely different places, and could well mean completely different types of wiring, this is not an issue.

It's the same situation as if you have wiring from the 1960s today - the fact it is in conduit or whatever is largely irrelevant, since far more socket outlets are required and lighting probably isn't a single lamp hanging down from the ceiling.

I suppose, I'll do it anyway, just on the off chance I'll need to do some work on any of it after the plastering has been done, me and the wife would be well peeved at having to pull the wires out of the wall just for the sake of £10 of conduit!

Thanks though