10mm twin/earth clipped outside wall in trunking or swa?

[eeb1933]

hi all

got a job where i,ve got to run a supply to shower. no way of running it through house so c/u is in garage and could go straight out up to soffit into loft, was thinking of doing it in swa, any of you done it this way or have you just put t/e in trunking.

?:|

 

[Sidewinder]

I don't like unnecessary joints, so, for me protected T&E, IF there is no other way.

Also it is gonna be big for T&E I guess 10 or 16mm thus you'll need safe access to any joint for maintenance to comply with wiring regs & CDM, unless you fit maintenance free joints and at 10/16mm these will probably be crimps?

 

[PC Electrics]

Yep, did just that in swa recently. Works fine. just use a galv box in the loft above to change to t&e or do it in the ceiling switch (use a Crabtree one).

 

[ianmacd]

Trunking is not designed for this use and neither is t&e so SWA would be the best way imho.

 

[roys]

As PC Electrics says use a galv box and as Sidewinder says keep joints to a minimum so secure the galv box right above the switch, gland the swa into the galv box then just using the galv box as a 'through' box ie no joint in it go straight into the switch with your cores. You will probably have to drill the box bottom at some point so that it lines up with the ceiling switch, so obviously a grommet or some other method will have to be used to make a safe edge.

I would put a dwang in, think in England it is called a noggin, piece of wood screwed in between the joists and lying on the ceiling if you see what I mean, then the box would be screwed onto this in the loft and the switch screwed into from below. Then a hole is drilled straight through the box, dwang and into the switch.

Not sure I have explained it very well, but it makes sence to me.

Agree with ianmacd, plastic trunking and t&e would be a poor choice.

Cheers Steve

 

[green-hornet]

I would go with swa just as the others have said. The crabtree shower switch has big terminals on, and are far better for 10mm cable, and will even take 16mm.

 

[Evans Electric]

Yes we've wired showers from the outside quite a few times , using SWA made off into an adapt. box and changing to T/E . I have no problem with jointing cable , if it needs to be jointed , joint it .

 

[Harvey]

Why use a galv box ? Why not plastic one

 

[Zeespark]

The SWA gland would more than likely deform a plastic box during and after installation Harvey, thats why, for a termination like that, a metallic enclosure is preferred.

Andy

 

[Dunx]

I think I quoted for that job!......

 

[binky]

Have used both options and prefer FTE in trunking, damn site easier to install, matches white PVC doors/windows/drainpipes etc etc. Given the number of cable runs I've seen over the years in FTE clipped to walls, suspended off cateneary wire, and still working after 20/30 Years, I would argue that well fixed PVC trunking is perfectly adequate mechanical and UV protection, especially when running up walls at high level, and will provide a reliable and long lived installation for many years to come. Two things I normally do are, leave the trunking well ventilated to prevent heat problems, and use decent sturdy make of trunking.

 

[sprocketflup]

As PC Electrics says use a galv box and as Sidewinder says keep joints to a minimum so secure the galv box right above the switch, gland the swa into the galv box then just using the galv box as a 'through' box ie no joint in it go straight into the switch with your cores. You will probably have to drill the box bottom at some point so that it lines up with the ceiling switch, so obviously a grommet or some other method will have to be used to make a safe edge.I would put a dwang in, think in England it is called a noggin, piece of wood screwed in between the joists and lying on the ceiling if you see what I mean, then the box would be screwed onto this in the loft and the switch screwed into from below. Then a hole is drilled straight through the box, dwang and into the switch.

Not sure I have explained it very well, but it makes sence to me.

Agree with ianmacd, plastic trunking and t&e would be a poor choice.

Cheers Steve

A 'dwang' ? every days a school day

 

[batty]

I have never used swa to wire a shower as I have only been asked to do one externally once and used tw/e in white trunking for this. I was not over keen on doing job but did and as it was at side of chimney it was not very noticible. I do like the SWA idea and if asked to do one again would probably go that route. I personally cannot see a problem using trunking apart from look of it on an outside wall but if this it what people want I would do it again.

 

[binky]

Looks nicer than SWA if done right, and avoids extra terminations with potential to burn out over time as discussed above.