Replacing service cable buried <50mm in wall

[rickmusik]

Hi..

We need to replace a 16mm twin and earth service cable that is buried in a wall in zone 2 of a bathroom. It is buried less than 50mm and unprotected by metal conduit or RCD.

It is being replaced by a SWA 25mm armoured cable, all terminations well away from the bathroom.

Is it OK to surface mount the SWA cable in plastic conduit or does it have to be chased into the wall &gt; 50mm?

The service cable is fed by a metal 100A Wylex switch fuse and feeds the metal CU in the flat above the bathroom using standard cable glands.

 

[Sharpend]

So this is a feed to another property passing through? 

Can the swa not be fixed on the external of the building? 

Why is it being changed in the first place? 

 

[Blue Duck]

You wont need 100a supply to a flat unless someones growing weed up there.

 

[ProDave]

It almost certainly complied with regs when it was installed. If you are not changing anything, there is no requirement to upgrade it now.

Why are you changing the cable for the upstairs flat and in the process trashing the bathroom downstairs?  I would do as sharpend suggests and run it up the outside of the building.

I would have no more than an 80A fuse in the switch fuse to try and discriminate from the suppliers fuse.

Put a dummy accessory at the top up near the ceiling to mark it for other sparks to show there is a safe zone there.

 

[Evans Electric]

Depending on how easy the options are  , think I'd go for the SWA  contained in PVC trunking .   But then on second thoughts  I'm sure you cannot pass other circuit cables through a bathroom  anyway .   I'd have to double check the regs  .

SO outside the  bathroom  or externally . 

 

[ProDave]

If I was the downstairs flat, I would not want the upstairs flat's supply inside my flat.