Channeling the wall for 2.5mm cable

[bodger67]

Buy the channeling chisel from Screwfix - i find mine goes through breeze with little effort with the hammer on its slowest speed, and makes a nice, clean channel with very little mess. I usually go deep enough that the cable goes straight up into the box without bending, cutting in two stages about 10mm each time.

The 20mm oval conduit Wickes sell can be a bit tight for two 2.5mm cables - anyone know if I can get anything wider elsewhere?

 

[dingbat]

sorry what i meant when i said not to cap if horizontal or vertical

was not to cap if horizontal or vertical between and accesory or a cu

sorry hope its clear now

reg 522-06-06

As has already been emphasised, capping does not provide mechanical protection from penetration, nor does it satisfy the requirements for a circuit protective conductor. Whether to use capping or not is not even covered in the regs, it's simply good practice.

 

[ban-all-sheds]

As has already been emphasised, capping does not provide mechanical protection from penetration, nor does it satisfy the requirements for a circuit protective conductor. Whether to use capping or not is not even covered in the regs, it's simply good practice.

Indeed - taking this question literally sums it up:

Interesting. So if I want to bed cable in my wall, I need to use metal capping, is that right?

You never need to use capping, metal or plastic.

i.e. you may want to use it, which is fine, but if ever you need anything to cover unprotected cables then capping, metal or plastic, is inadequate.

 

[roccodelucca]

i.e. you may want to use it, which is fine, but if ever you need anything to cover unprotected cables then capping, metal or plastic, is inadequate.

If metal or plastic is inadequate then what indeed is adequate, oval metal conduit ?

 

[didthathurt]

If I'm about to cut the channels for a ring-main circuit, what width/depth would you recommend?

Don't forget, no deeper than 1/3rd of the thickness of the wall if it's a brick/block built wall. (Part A)

 

[Lectrician]

How many jobs will jo-nob need to go back to to put right then

You don't need to cap or tube any cables if run in the 'safe zones' - which actually extend beond just hor/ver of accessories (and CU....which is an accessory).

If you run outside of a zone, you need to go deep enough, as said......or provide EARTHED protection - or protection that will prevent penetration. (rarely an option).

The oval conduit/capping etc is used as a preventitive measure against damage from builders tools - trowl and float etc when scimming the wall.

The norm in my area is to cap cables on dry lined walls, and use oval tube on rendered walls.

 

[roccodelucca]

How many jobs will jo-nob need to go back to to put right then

You don't need to cap or tube any cables if run in the 'safe zones' - which actually extend beond just hor/ver of accessories (and CU....which is an accessory).

If you run outside of a zone, you need to go deep enough, as said......or provide EARTHED protection - or protection that will prevent penetration. (rarely an option).

The oval conduit/capping etc is used as a preventitive measure against damage from builders tools - trowl and float etc when scimming the wall.

The norm in my area is to cap cables on dry lined walls, and use oval tube on rendered walls.

Thank's for that info' I always feel safer protecting power cables, the woman in my house has put some pictures up in some strange places and hell if anything happened to her I'd have to learn to cook n' clean so thank's again Lectrician

 

[75pete]

This is an OLD post but i have the same question. Is the Ans. still as this old post or have things changed?

Thanks
pete

 

[ban-all-sheds]

It's the same, but BS 7171:2008 adds the reqirement to RCD protect nearly all cables buried at a depth pf <50mm.

See IEE Article on 17th Edition requirements for concealed cables.

 

[MisterG]

The 20mm oval conduit Wickes sell can be a bit tight for two 2.5mm cables - anyone know if I can get anything wider elsewhere?

You can get 25 mm oval conduit from various sites on the web, just google it.

Cheers

G

 

[ban-all-sheds]

bodger67 asked that question nearly 6 years ago.

I expect he's found some conduit by now.

 

[MisterG]

bodger67 asked that question nearly 6 years ago.

I expect he's found some conduit by now.

Lol, I didn't check the date, I assumed it was a new thread. Just goes to show you should never assume!

 

[IJWS15]

or even as a second choice

Or ever . .

Once used one to cut out a wall below a newly installed lintel into a new Kitchen, after 30 seconds I could not see the chalk line I was following from a foot away, could only see a dim glow from the window, dare not walk out because I knew there were things laid on the floor I could no longer see, took a long time for the dust to settle!

 

[MalcofArabia]

Just a foot note to this, and perhaps showing age here, but I was always led to believe that not only do you put the cable in oval tube or capping just as good practice or to avoid plasterers tools, but the PVC over the years could deteriorate if buried directly in the wall

I wonder if the 2004 post as cleared all the meess up yet

 

[ban-all-sheds]

I think brick & plaster dust is like holiday sand and Christmas tree pine needles - you never get rid of every last trace...