Capping or No Capping?

[eveares]

So lets say you were doing a re-wire and needed to chase out walls to run new cables, would you bother using capping over the new cables before plastering over the chase to fill it in, and if so, would you use plastic or metal capping?

I know that both plastic and metal capping provide no mechanical protection under BS7671 and are there just for the sake of the plastering process.

Another similar question is when fixing cables on internal brick walls, do you prefer galvanised banding, normal metallic cable clips or something else to fix the cable to the wall?

It seems like these type of questions can generate a lot of inconsistent answers and open a can of worms from looking online.

Regards: Elliott.

 

[EFLImpudence]

It seems like these type of questions can generate a lot of inconsistent answers and open a can of worms from looking online.

That's because there are no definitive answers.

It is personal opinion and as such equally up to you to do what you prefer.

 

[JohnW2]

I know that both plastic and metal capping provide no mechanical protection under BS7671 and are there just for the sake of the plastering process.

If you utilise a decent plasterer (and there are plenty around, since the work of 'bad plasterers' is usually very apparent to 'lay' eyes!) you don't really need any 'capping'.

If you're going to do the plastering yourself, only you can judge how like you are to damage uncapped cables

 

[phatboy]

I always use plastic conduit (Not capping). It is possible to replace a cable in the future, if you are very careful and have access to the other end of the conduit. Fix it as required with plumbers banding.

 

[JohnW2]

I always use plastic conduit (Not capping). It is possible to replace a cable in the future, if you are very careful and have access to the other end of the conduit. Fix it as required with plumbers banding.

That's the theory, but I have to say that my experience is that, unless one uses very generously-sized conduit, subsequent 'replacing the cable' is much easier said than done

 

[sparkwright]

Always a good idea to use capping or conduit.
If a cable should get drilled through, you have a chance of pulling the cable through, to minimise damage.
Secure capping or conduit with galvanised clout/plasterboard nails.

Why people think banding is the answer, I do NOT know.
Just more messing about, and I doubt you will get the conduit anywhere near as secure as you would with galv nails either side.

 

[Scally-Ho]

My opinion for what it's worth is round plastic conduit and larger than needed to allow pulling through if needed to replace a circuit. If any bends needed then pull as long a radius as possible before rapid cooling to set the bend. Nothing worse than an expensively papered/decorated room destroyed to gain access to one circuit or another.

 

[phatboy]

That's the theory, but I have to say that my experience is that, unless one uses very generously-sized conduit, subsequent 'replacing the cable' is much easier said than done

I've done a few recently, due to adding sockets to a ring. 20mm oval conduit.

Strip the ends of each cable, cut the L and N off, and twist the CPCs tightly together. Cover in tape from outer sheath to outer sheath. Washing up liquid on the cable, and drip a bit on the hole for a cable going down, and ive had 1 failure out of 6.

 

[pete01]

Chased and plastered I would use capping

Block then dot and dab I would just clip

 

[JohnW2]

I've done a few recently, due to adding sockets to a ring. 20mm oval conduit. .... Strip the ends of each cable, cut the L and N off, and twist the CPCs tightly together. Cover in tape from outer sheath to outer sheath. Washing up liquid on the cable, and drip a bit on the hole for a cable going down, and ive had 1 failure out of 6.

I suppose 20mm conduit isn't too bad, but I'm sure that, over the many I've tried to do in my time, I will not have had as few as 1 in 6 failures.
I would do exactly as you describe, but with one addition - I would solder the twisted CPCs together because, at least in my experience, if one doesn't then the most common mode of failure is the coming apart of twisted-together CPCs (if, as is often the case, one has o pull fairly hard)

 

[JohnW2]

Chased and plastered I would use capping

Why? Is it perhaps because you don't know a plasterer who you can 'trust'?

 

[pete01]

Why? Is it perhaps because you don't know a plasterer who you can 'trust'?

Just always have, just to keep cables in place mainly, can't help it.

 

[pete01]

Why? Is it perhaps because you don't know a plasterer who you can 'trust'?

Would you just clip a cable that will be plastered over? Doesn't seem right does it?

 

[EFLImpudence]

So lets say you were doing a re-wire and needed to chase out walls to run new cables, would you bother using capping over the new cables before plastering over the chase to fill it in, and if so, would you use plastic or metal capping?

 

[JohnW2]

Would you just clip a cable that will be plastered over? Doesn't seem right does it?

Seems right enough to me That's what I'd do, but wouldn't necessarily even use formal 'clips' - I might well just 'jam it into the chase with 'bits and pieces' (sometimes little bits of T+E!), maybe nails, to keep it in place until it was plastered over.

Is something like that not what most people do?