Wires hidden in a wall.

[joeb99]

Hi,

What is the normal way to protect cable that is in a wall and will be plastered over? The cables are going to run horivontal and vertical.

It always used to be a peice of metal sheeting over the cables, but im not sure what to use now, if anything at all!

 

[equitum]

if its going to be plasterboard over the top with dot and dab then I just clip direct to wall, if going to plastered with browning then I will usually use the galv capping just to help out the plasterer and protect cables from trowell/getting disturbed etc.

 

[joeb99]

Ahh, capping! Thats what it is called!

Now there appears to be 2 types; Galvanised or PVC. What are the advantages (excluding cost) of the two?

The wall will be hardwall'ed then multi-finish. Currently bare brick.

 

[jj4091]

if its going to be plasterboard over the top with dot and dab then I just clip direct to wall,

Only if it is in a safe area! PVC capping only offers protection against plasterer's trowels etc. Galvanised metal must be used in non-safe areas & should be earthed, it is not particularly protective aginst drills & nails but better than nothing.

 

[joeb99]

it is not particularly protective aginst drills & nails but better than nothing.

Been there, done that! Oooch!


Thanks for all the help.

 

[plugwash]

whether metal capping even if earthed complies with the regs for cables out of zones is somewhat dubious to say the least.

It doesn't surround the cables as is specified in the earthed protection requirements and doesn't really provide much mechanical protection either.

 

[joeb99]

but if you hit a nail into it, then into the live, the earth path will be through the capping, not you.

I know its not the best solution, metal pipe would be a better solution, but if i put pipe in the walls, my plasterer will put a bucket of muck over my head.

 

[Taylortwocities]

but if you hit a nail into it, then into the live, the earth path will be through the capping, not you.
.

That is only a true statement if the metal capping is earthed properly and through its entire length. In many years of sparking i have never seen metal capping that is earthed.

If the cables are not in safe zone (horiz or vert from a socket etc) or more than 50mm deep from the surface it must be run in earthed steel conduit. So, it will upset your plasterer. Better that than have a death on your hands when a nail gets driven into the hidden cable run.

 

[joeb99]

The cable will be horiz or vert form the sockets, and i'll earth the capping just to be on the safe side.

 

[Taylortwocities]

If it runs H or V from sockets you dont need to worry, just pop it behind the dot&dab and yr away.

 

[joeb99]

No dot/dab, its being hardwalled, then skimmed.

Im going to use galv 20mm pipe for the horz, and capping for the vert runs - both earthed.

That should be ok. I can channel in 20mm with a grinder no problems to keep the plasterer happy.

Im going to hang stuff on the wall near the cables, so i want to not kill my self too!