How would this shower cable be routed?

[smp50]

My shower and its main switch are currently to be found in one corner of a rectangular bathroom (roughly 2 x 3m). I'm considering the possibility of moving it to the diagonally opposite corner, where there is a water supply but no electricity.

The bathroom is in a single-storey, ground-floor extension and there's no room above it to go pulling up floorboards. It has a flat roof with felt on it. The ceiling inside has artex and coving.

If I were to have this job done, what route would the electrician most likely take to get from the switch (whose position is fine) over to the new shower position? Does it depend really a lot on the layout and structure of the room or is there a likely route it would take? Is it going to have to go through the ceiling one way or another?


Thanks for any input. I'll get quotes at some point but some hints now would help me plan things.

(Note that running a brand new cable from the CU wouldn't really achieve much as it would have to go further and pass through the same walls and ceilings, still in the extension).

 

[pjcomp]

If the cable is to be completely hidden it will mean opening the ceiling, drilling through joists to run the cable, then replastering and redecorating the ceiling. If you don't mind the intrusion on the decor, trunking can be run round the room at coving level with the cable inside that.

Depending on what's outside the bathroom it could go out through one wall, round the outside, and back in where you want the shower. Or you could chase down the wall, run it under the floor and back up the other side.

At the end of the day it depends how much disruption and make-good you're prepared to accept (with attendant cost) and what your preferred aesthetic is when it's done.

pj

 

[smp50]

If the cable is to be completely hidden it will mean opening the ceiling, drilling through joists to run the cable, then replastering and redecorating the ceiling. If you don't mind the intrusion on the decor, trunking can be run round the room at coving level with the cable inside that.

Depending on what's outside the bathroom it could go out through one wall, round the outside, and back in where you want the shower. Or you could chase down the wall, run it under the floor and back up the other side.

At the end of the day it depends how much disruption and make-good you're prepared to accept (with attendant cost) and what your preferred aesthetic is when it's done.

pj

Thanks for the ideas - the outside route would work rather well, actually - presumably with the cable set into some kind of expensive exterior trunking. But then even indoors it all has to be armoured, doesn't it. There are already significant areas of damaged plaster so it may be ok to create a few more.

Would I be allowed to do any of the work, cutting chases and refilling them? Or is that all part of what I'm not allowed to touch seeing as it's in the bathroom?

 

[STEVEROG]

You can get plastic skirting that's designed to take pipes and cables within. You could use this instead of trunking. It provides loads of room and you can replace the existing skirting board, assuming that you have standard timber or even worse, MDF skirting in the existing room? The plastic skirting is far more suitable in a moist area like a bathroom.

 

[smp50]

You can get plastic skirting that's designed to take pipes and cables within. You could use this instead of trunking. It provides loads of room and you can replace the existing skirting board, assuming that you have standard timber or even worse, MDF skirting in the existing room? The plastic skirting is far more suitable in a moist area like a bathroom.

I thought that was only for low voltage stuff, signal cables. Is it armoured somehow, the skirting for power cables?

I might be putting up wood cladding around the lower half of the room so that could hide the main horizontal travel of the cable, only needing to be chased down from the old shower and back up to the new one. Again, presumably armoured somehow. And set back a minimum distance from the surface, or whatever the rules are. I did look into it all for a non-wet room and it was such a faff that I just dropped the spur down from a room above instead of trying to take one around the walls.

 

[Taylortwocities]

The cable would need to be run in safe zones (see WIKI), or "set back" at least 50mm from the surface, or it could be armoured cable, or run in steel conduit.

 

[EFLImpudence]

The cable can run behind coving.

 

[dhutch]

The cable can run behind coving.

This.

Or, have the ceiling down, the cable run where you want, and then get a plaster in to skim over it all flat. Quick, easy, nice and neat, and I prefer a smooth ceiling to artex. £20 for the plasterboard and plaster, £80-95 for the plaster.

That's what I would do anyway, having done the same in all my bedroom ceilings to insulate the sloping section.


Daniel

 

[smp50]

Thanks for the ideas, seems like there are a lot of ways to do it.

What I need to do really is calculate the cost of running an electric shower vs. using hot water from my old Baxi Bermuda back boiler, and see if it's even worth moving the electric one or just getting a mixer down in the other corner.

 

[smp50]

Thanks for the ideas, seems like there are a lot of ways to do it.

What I need to do really is calculate the cost of running an electric shower vs. using hot water from my old Baxi Bermuda back boiler, and see if it's even worth moving the electric one or just getting a mixer down in the other corner.

It seems that 10 minutes of electric shower operation every day costs about the same as my boiler's pilot light does, i.e. £70-90 per year...

But I have no idea how much it costs to get hot water off it as I've never actually had it in use properly yet. And the system is all drained currently.

 

[dhutch]

The calculation for shower running is cost is quite easy, as i expect you have realised.
- Power consumption, multiplied by the time used, multiplied by the cost of the elec. Ensuring all the units stay correct.

For the shower the sums are going to go a bit more like this.
- Flow rate of water, energy required to raised it by x degrees, efficiency of boiler, cost of that energy. Plus if would otherwise have it off, cost of the pilot light... (maybe for the 6months the heating if off, if its the only hotwater you use?)

The only other way, which is what I did once with my combi boiler, if to set the shower running, wait a moment for it all to settle into equilibrium, and then outside to the meter, and time how long it took for each unit to tick by. But obviously that needs it to all work, and is more complex for a stored-hot-water system!

It also presumes that the boiler and water supply can provide a good shower.


Daniel

 

[smp50]

The calculation for shower running is cost is quite easy, as i expect you have realised.
- Power consumption, multiplied by the time used, multiplied by the cost of the elec. Ensuring all the units stay correct.

For the shower the sums are going to go a bit more like this.
- Flow rate of water, energy required to raised it by x degrees, efficiency of boiler, cost of that energy. Plus if would otherwise have it off, cost of the pilot light... (maybe for the 6months the heating if off, if its the only hotwater you use?)

The only other way, which is what I did once with my boiler, if to set the shower running, wait a moment for it all to settle into equilibrium, and then outside to the meter, and time how long it took for each unit to tick by. But obviously that needs it to all work!

Yea, I guess I'd just put the boiler on to do hot water for an hour, then run it all out of a tap to see how much it managed in that time and think if it would be enough for a shower. I don't anticipate many other uses for hot water in this house, but it depends who lives here. I use the cold tap for everything and can boil a kettle for washing up.

It also presumes that the boiler and water supply can provide a good shower.

Indeed! I really don't know.

I live alone and have the boiler off altogether year-round (no need to CH or DHW) but when I get a lodger or let the whole house then they'll presumably want both operational! In which case there'll probably be a huge amount of hot water being cooked up that doesn't really get used and would be wasted otherwise? Very hard to know.

I'm going to try to get the system up and running and then run some tests like you suggested.

 

[dhutch]

Yea, I guess I'd just put the boiler on to do hot water for an hour, then run it all out of a tap to see how much it managed in that time and think if it would be enough for a shower.

Yes, sorry, meant to say that mine was a combi-boiler setup, post now edited. But yes, that would be one way to empirically test your setup.


Daniel