I will be installing a couple of runs of cable (some twin core and earth and some flex) under a patio area. Can a 20mm rigid plastic conduit be used to encase the cables? Is this a satisfactory (and cheaper) alternative to using SWA?
SWA Armoured Cable Alternative?
- Thread starter EViS
- Start date
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No.
522.8.10 Except where installed in a conduit or a duct which provides equivalent protection against mechanical damage, a cable buried in the ground shall incorporate an earthed armour or metal sheath or both, suitable for use as a protective condutor....
PVC conduit is NOT suitable for this
522.8.10 Except where installed in a conduit or a duct which provides equivalent protection against mechanical damage, a cable buried in the ground shall incorporate an earthed armour or metal sheath or both, suitable for use as a protective condutor....
PVC conduit is NOT suitable for this
It would be cheap(er) but not satisfactory.
Thanks for the prompt replies chaps. Why would this be unsafe, seeing as the cable (and conduit) would be chased into the concrete bed of the old patio and under 50 mm concrete slabs of the new patio? (genuine question, I'm not trying to be argumentative 
)
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Are there any areas where it will not be under the concrete ?
Nope, it will come out of the wall, down behind the render, under the paving, up another wall (400 mm above ground level) and into a socket.
What happens if one of the slabs gets damaged and needs to be replaced or the patio gets removed?
I know it's not the answer you want to hear but SWA (or pyro or earthed steel conduit) is the only way to do this job properly, safely and in compliance with wiring regulations.
Is the cable behind the rendering going to be within a prescribed safe zone?
I know it's not the answer you want to hear but SWA (or pyro or earthed steel conduit) is the only way to do this job properly, safely and in compliance with wiring regulations.
Is the cable behind the rendering going to be within a prescribed safe zone?
Apart from what has been said -
Plastic conduit offers NO protection (drill holes in it, hammer nails through it, hit it with a pick, strike it with a spade - did you feel any resistance?)
So, in effect, you are wanting to bury T+E unprotected.
Do you think it wise?
Plastic conduit offers NO protection (drill holes in it, hammer nails through it, hit it with a pick, strike it with a spade - did you feel any resistance?)
So, in effect, you are wanting to bury T+E unprotected.
Do you think it wise?
My thinking is that when the patio gets replaced one day, the plastic conduit will be immediately obvious, especially when combined with a warning tape covering it.
The cable will be some 30mm into the blockwork, so will be in a 'safe zone' as far as I'm concerned, happy to hear any advice on this though.
If I do go down the path of using SWA, can I remove the 'armour' from the point that the cable touches the bottom of the wall at ground level and run the inner cable up the wall (it would look like flex)? SWA does not bend easily and wouldn't give me the correct radius to bend into the wall and be covered with render.
Maybe maybe not who knows but I certainly wouldn't be happy with this installation, and as far as I'm concerend it does not comply with the wiring regs or building regs.
So the cable will not be in a safe zone then.
You must use SWA for the entire run.
It must not be cut off or bared back or anything else. It must run right up to the socket, and all the way inside the house. How exactly do you think you'd earth the armour if you cut it off at ground level?
The more you say the more I'm beginning to think you out to engage an electrician to do this work for you so that you don't bodge it up and end up with an unsafe and illegal installation.
So the cable will not be in a safe zone then.
You must use SWA for the entire run.
It must not be cut off or bared back or anything else. It must run right up to the socket, and all the way inside the house. How exactly do you think you'd earth the armour if you cut it off at ground level?
The more you say the more I'm beginning to think you out to engage an electrician to do this work for you so that you don't bodge it up and end up with an unsafe and illegal installation.
Right, all clear, thanks pal . Have started a new thread asking whether I can use 1.5mm SWA for two sockets, or whether I would need 2.5mm.
What would you consider a 'safe' zone for the part of the cable running up the wall mate? 30mm blockwork + 20mm render not enough?
. Have started a new thread asking whether I can use 1.5mm SWA for two sockets, or whether I would need 2.5mm.What would you consider a 'safe' zone for the part of the cable running up the wall mate? 30mm blockwork + 20mm render not enough?
Thanks bud, so as I'm burying to 50mm from the finished wall surface, I am in the safe zone by the looks of things.
Well you're not though are you. You said a chase 30mm deep plus the rendering of 20mm = 50mm minus the size of the cable = >50mm so it's not in a safe zone.
I know you don't want to here any of this, and you're going to keep arguing until someone agrees with you and then go away and do your dodgy lash up just like you planned all along.
You've been told the proper and safe way to do the job.
It's up to you wether you chose to do it properly or not.
I know you don't want to here any of this, and you're going to keep arguing until someone agrees with you and then go away and do your dodgy lash up just like you planned all along.
You've been told the proper and safe way to do the job.
It's up to you wether you chose to do it properly or not.
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