First Fix

[stevefizz]

We are having a new kitchen extension built with a vaulted ceiling and a solid floor.

from what I have been told the first fix electrics will be done after the roof goes on. Can the cables go in conduit in the wall cavity or do you use “top hat” or oval conduit between the wall and the plasterboard. The other question is how much space do you normally get between the wall and the plasterboard, enough for a 6mm cooker cable.


I am not doing this myself just curious about how it should be done

Thanks
Steve

 

[jj4091]

The answer to all your questions is yes, but if the walls are being dry lined then the cable would normally be clipped to the wall under the plasterboard

 

[RF Lighting]

You are not supposed to drop cables down the cavity.

The cavity could be (and probably will be on a new extention) filled with thermal insulation, which reduces the cables current carrying capacity.

The cable can bridge the cavity and cause problems with damp.

The cable cannot be supported at appropriate intervals

No one will be expecting the cable to be there which could lead to it getting damaged in the future.

You should run the cable on the face of the internal wall. Additional protection is not required, but is IMO it is good practice to install it. I prefer oval conduit.

The gap between the blockwork and the plasterboard will be big enough to allow an oval conduit not chopped in.