Installing cables in an external wall

[Paul205]

thinking laterally, am I required to drill a hole at 90 degrees through a wall?? With a long drill bit I may be able to angle the cable through the wall so it came out withing 150mm from a corner. This will probably require an angle of around 45 degrees

Once again, I will ask the electrician, I just want to go to him with a credible proposal

 

[PrenticeBoyofDerry]

Your not required to drill at 90 degrees, you can angle it but not at 180
Providing the cable cannot be penetrated outside the permitted safe zones by a 50mm pointy thing, you should be fine!

 

[JohnW2]

thinking laterally, am I required to drill a hole at 90 degrees through a wall??

No - on the contrary, it should be angled downwards towards the outside, so that water can't run in to the house.

With a long drill bit I may be able to angle the cable through the wall so it came out withing 150mm from a corner.

That would involve doing some careful geometrical investigations, to make sure that none of the path of the hole came within 50mm of the inner surface of the wall other than in a safe zone. You might well also have to undertake similar checks on the outside surface of the wall - one doesn't usually have to think about safe zones outdoors!

Kind Regards, John

 

[Paul205]

thanks guys, all comments greatly appreciated. Out of interest, is there such thing as a maintanance free earth clamp?? ie one that could be used to clamp to metal conduit but would be screwless?

 

[JohnW2]

thanks guys, all comments greatly appreciated. Out of interest, is there such thing as a maintanance free earth clamp?? ie one that could be used to clamp to metal conduit but would be screwless?

There are certainly clamps which clamp to the pipe/conduit by spring action, not screw, but they will still usually have a screw connection to the cable - so would not be 'maintenance free' in the junction-box sense. Why do you ask, and what conduit are you thinking of?

Kind Regards, John

 

[Paul205]

well a previous suggestion was to use metal conduit. My electrician said this would need to be earthed and this could be done in the light fitting (which would be an ache), he dismissed the use of an earth clamp elsewhere as I have no way to inspect it as it would be in an inaccessible ceiling void.

The light fitting would possibly permit the entry of 10mm conduit.

 

[JohnW2]

well a previous suggestion was to use metal conduit. My electrician said this would need to be earthed and this could be done in the light fitting (which would be an ache), he dismissed the use of an earth clamp elsewhere as I have no way to inspect it as it would be in an inaccessible ceiling void.

Ah. Conduit is usually earthed by being connected to an earthed accessory box at one or both ends, but I suppose that may not be the case with what you are thinking about. Could you not extend the conduit to somewhere which was accessible?

Kind Regards, John

 

[Paul205]

I don't know John, after all this it may transpire I actually want the lights in a safe zone. The other half is going to give her thoughts on where we actually want the lights. I think they look better in the unsafe zone but its a team decision!

 

[JohnW2]

I don't know John, after all this it may transpire I actually want the lights in a safe zone. The other half is going to give her thoughts on where we actually want the lights. I think they look better in the unsafe zone but its a team decision!

Ah - well, in that case, let us know when someone has won

Kind Regards, John

 

[sparkwright]

I think common sense has to be applied here.

The so called earth shield cable will still get damaged if it gets drilled, so it's a waste of time considering that.

Same goes for SWA.

You've still got the problem of repairing it.

That leaves two options - earthed steel conduit. Earthing it could be bothersome, one way would be to fit an end/terminal box on the end where it passes through the wall. Have the inspection hole facing the outside. Connect a seperate 4 mm earth wire from the outside light to the earth terminal on the conduit box. Yellow ring terminal and 4 mm brass screw. (Fit bush end at other end.)

Unfortunately hidden screw terminal.

Technically wrong, but... what can you do?

The other option, again as suggested, drill holes at angle to end up in safe zones, also bend the rules slightly so cable passes through cavity also at an angle.

As I said, common sense has to be applied here, and I really think a cable that isn't going to get easily drilled through is far more important than a concealed earth screw or a cable not passing directly through a brick cavity.

 

[JohnW2]

I think common sense has to be applied here.

I agree.

In fact, as far as I can make out, this entire complex discussion (some relating to potentially quite complicated work) arises from the fact that the OP does not want short visible lengths of cable (or conduit) on his external walls, from just above ceiling-level down to each of the lights. I cannot help but wonder whether he should not consider re-visiting that decision!

Kind Regards, John

 

[Paul205]

Wash your mouth out with soap John!! There would be two 1m vertical runs of either cable or some form of conduit both sides of my front door uurrgggh!!!

 

[JohnW2]

Wash your mouth out with soap John!! There would be two 1m vertical runs of either cable or some form of conduit both sides of my front door uurrgggh!!!

Views about aesthetics vary! Seriously though, I'm having trouble in picturing the arrangement - particularly how the middles of the walls of the new toilet room and shower room would be at the sides of your front door. Maybe a rough sketch, if you could produce it, would help me understand.

Kind Regards, John

 

[bernardgreen]

Front door leads directly into the shower room ? Would be handy for a quick shower when coming home after a long energetic jogging session.

 

[ban-all-sheds]

I really do not want to run the cable down the external brick in SWA etc

Find an electrician who can do pyro - have him run it in the gaps between the bricks, and point over it.