Getting ring main ends to CU under the stairs

[jpowell79]

I'm having the house re-wired at the moment. A friend of mine who is a fully qualified electrician has offered to come in for a few hours and fit a new CU for me (Hager Design 30, fully loaded with RCBO's) and he knows I'm fairly competent, so am good to do most of the donkey work (chase walls, run cables) with him to finish it up.

Anyhow I've just ran a completely new upstairs ring and have left the tails under the floorboards of the upstairs landing.

I've already pestered my mate enough with questions about this, so I was hoping I could figure this one out for myself (with maybe a little help from people on the forum!)

so if you look at the side view of the house, the consumer unit is going under the stairs, and the 2.5mm T&E tails are under the floor boards on the first floor. Obviously the tails are not "directly" above the current CU (as indicated by the second "top-down" picture) as the cu is on the wall whereas the tails are under the landing.

So my question is, what's the best route to get the tails back down to the CU? I know I can't go directly through the stairs as that's part of the safe zone.

So do I go under the bath in the bathroom, then down into the kitchen? This is not ideal as it will mean ripping the kitchen apart?

Can I go outside the property and down the outside wall, then back in again?

Should I go across to the box room, then go straight down that wall? The problem with this is that I'd then need to go horizontal along the wall (The ground floor is solid concrete).

Any suggestions?

 

[ban-all-sheds]

Whether you regard it as "pestering" or not, the only suggestion that can be made is that you must ask your electrician.

He's a friend - how can you possibly ask him to sign official documents to say he did something which he did not, i.e. doing the design. People don't ask friends to lie.

When you applied for Building Regulations approval, what did you tell Building Control would be your way to ensure compliance with Part P?

 

[securespark]

Can't you come down on the side of the under-stairs cupboard closest to where your tails are at the moment, then cross the cupboard once they are inside it?

 

[jpowell79]

Can't you come down on the side of the under-stairs cupboard closest to where your tails are at the moment, then cross the cupboard once they are inside it?

I didn't think I could run it along any structural part of the stairs?

 

[jpowell79]

Whether you regard it as "pestering" or not, the only suggestion that can be made is that you must ask your electrician.

He's a friend - how can you possibly ask him to sign official documents to say he did something which he did not, i.e. doing the design. People don't ask friends to lie.

When you applied for Building Regulations approval, what did you tell Building Control would be your way to ensure compliance with Part P?

He's a mate, but we're not best buddies and he's not seen our new house yet, so I don't really want to ask him to be doing a 90-minute round-trip to Essex, just to say to me "just run them down there" then be off again!

Of course I want everything to be compliant and he won't sign it off unless he's happy with it.

Ah well I've spent half hour making drawings for the forum... I may as well email them to him as well

 

[ban-all-sheds]

Of course I want everything to be compliant and he won't sign it off unless he's happy with it.

People don't ask "mates" to lie, either.

When you applied for Building Regulations approval, what did you tell Building Control would be your way to ensure compliance with Part P?

Ah well I've spent half hour making drawings for the forum... I may as well email them to him as well

Good idea.

 

[John D v2.0]

Ours are similar, all the cables between the floors have to get under the stairs somehow, so the previous electrician just drilled diagonally through the trimmer at the top of the stairs and followed the side timber of the stairs down. They're in the safe zone at ceiling level, and partly in the safe zone at the side of the stairs, but not really. But I know they're there and no one would add a shelf there anyway. Probably been like that since rewired in the 70s and probably similar before that rewire too.
Once they're under the stairs they're exposed so not subject to safe zones which makes things easier.

 

[securespark]

Isn't that vertical line next to the CU a wall? Is it a hollow wall?

 

[EFLImpudence]

You likely do not require a ring for upstairs so that will save you one cable.

 

[jpowell79]

Isn't that vertical line next to the CU a wall? Is it a hollow wall?

yep it's a wall, but the problem is that at the top of that wall you are then directly under the last couple of steps on the stairs.

These look like the most likely options:

in conduit going through the kitchen (my least favorite option!)

going outside the house via the boxroom (definitely the easiest option, but not sure about running ring mains outside the property?)

chasing down the wall via the boxroom, then running behind the stairs (not keen on horizontal chases, but might be the only option)

Now I've drawn it out, it's looking most likely to be the third option, unless there's something obvious I'm missing?

Is it OK to "tweak" option 2, to channel straight down on that wall (where the brown line is) or is that still classed as the safe zone?

 

[EFLImpudence]

You're making a meal out of this.

If you are rewiring, where do the cables run at the moment?

What about upstairs lights and any other necessary circuits?

And downstairs lights, of course.

 

[securespark]

You're making a meal out of this.

Electrical spaghetti - Yum!

 

[jpowell79]

You're making a meal out of this.

If you are rewiring, where do the cables run at the moment?

What about upstairs lights and any other necessary circuits?

And downstairs lights, of course.

am not sure yet.....my old 1960's consumer unit only has 2 switches - lights and sockets..... both go through the wall into the kitchen. At that point they go behind the kitchen units. The first unit closest to the separating wall is a built-in gas oven, and I don't fancy pulling all that out to trace where the wires go.

Presumably, they all then head up to the floorboards under the bath in the bathroom then off to other rooms.

As I say, apart from ripping the kitchen apart, it's difficult to tell, hence the thought of taking a more convenient route

 

[jpowell79]

if I did it this way (but internally with a chase running down the wall) I suppose I could just put an electrical blanking plate in front of it on the wall, close to the stairs (fairly non-obtrusive) to indicate a vertical cable run?

 

[JohnW2]

if I did it this way (but internally with a chase running down the wall) I suppose I could just put an electrical blanking plate in front of it on the wall, close to the stairs (fairly non-obtrusive) to indicate a vertical cable run?

We've discussed this before, and I don't think there is any certainty (or, at least a consensus about a certainty) that, strictly speaking, a blank plate with no 'connections' behind it necessarily creates a 'safe zone' - although, in common sense terms, it obviously goes a long way towards achieving that.

Kind Regards, John