When An External Cavity Becomes An Internal Cavity

[Barx]

In my new house, the consumer unit is on what used to be the external wall, under the stairs. But the property was extended 15 years ago an now this wall is within the building. Is there anything stopping me now using this cavity? I'm rewiring and it will be a pig to get under the stairs to the ccu but a doddle to drop down the cavity. In fact there is some old vir in to use as a draw wire left at last rewire. The cavity insulation is the white fluffy stuff which as far as I know doesn't eat the cable like polystyrene balls do.

Cheers

 

[Murdoch]

Good question!

I would say its OK but lets see what other contributors think!

 

[Essex1]

Probably the wrong forum for a building question. Electrically no issue at all. I can not see a reason why not from a building point of view but I am not a builder.

 

[Andy™]

apart from the obvious de-rating for the insulation, cant see any issues with it

 

[steptoe]

Cables adequately supported along there length,

That's the only thing I can think of, 

Hardly a hanging offence, but what do I know. 

:C  

 

[Barx]

Probably the wrong forum for a building question. Electrically no issue at all. I can not see a reason why not from a building point of view but I am not a builder.

Nothing really a building question as the build has long since been done. It's a question of using the now internal cavity as a route to the ccu. Cheers

Cables adequately supported along there length,

That's the only thing I can think of,

Hardly a hanging offence, but what do I know.

:C

I thought of this a little, then I thought are they any less supported than a vertical conduit drop?If I do go for the route. I may chuck the cables in some 25mm copex down the cavity bit more protection. A bit less insulation factor, etc, etc

 

[NozSpark]

What are you worrying about?

Bridging the cavity is irrelevant as both sides are warm..

The only issues are cable support and derating due to insulation.

 

[kerching]

Was there not/is there not some reg about maximum unsupported vertical length of 5 m?

I am sure there was last Century?

Just vaguely remembering

 

[Rob_the_rich]

just a thought. would the top of the wall have any chance of water ingress, eg loose coping stones, exposed outer skin, condensation etc. I am thinking there should be a loop downwards before going through the "inner" wall to stop drips entering the CU.

if there is a lot of water it would normally drain through the outer wall, which is now plastered I assume, are there damp patches?

 

[Manator]

There are a couple of factors to consider most have been mentioned before, I do know that when bridging a cavity it is a good idea to provide mechanical protection to protect the cable from falling debris. I do not think you would have this problem so the only thing left is supported cable, I doubt it would be a crime for an internal wall at most 3m,then insulation. So I do not see any problems with what you propose.

 

[M107]

Crack on & get it done Barx, the only issue I can see would be that what has already been spoken of ......cable support along the length of the drop

If you don't worry about it neither will we

 

[Barx]

Sound, cheers boys.

The drop is only 2m max. Probably more like 1.7. Above is plastered both sides. Bathroom on one side, bedroom other. No damp. Downstairs the outside is a carport but the builder is about to close it in to be a utility room. So yes, dry and warm both sides.

Thanks again

 

[Evans Electric]

2 Mtr drop !..................... Just drop 'em in , they'll be fine  Barx .   

You're doing the classic Sparky thing that I posted about ages ago where we we are subject to so many rules & regs , some guys are frightened to open the toolbox .

Your house ...your cavity ... shove what you want up it !!!  :innocent

 

[kerching]

.....and remember, at the end of the day WHO actually cares?

The earth will carry on spinning

The tide will,come in and go out

We will,carry on sending EC on holiday and buying pies fo TC

We will bow to ANY minority

We will look after ANYONE Elses country but our own....anybody noticed any foreign aid coming in for the recent flooding? Anybody? Anybody At all??

In the words of Nike.......Just do it!

 

[Evans Electric]

.....and remember, at the end of the day WHO actually cares?

The earth will carry on spinning

The tide will,come in and go out

We will,carry on sending EC on holiday and buying pies fo TC

We will bow to ANY minority

We will look after ANYONE Elses country but our own....anybody noticed any foreign aid coming in for the recent flooding? Anybody? Anybody At all??

In the words of Nike.......Just do it!

Yes  ..... arn't all those feckers  in Calais trying to come over to help as volunteers ...........no ...... oh ..why do they want to come then ?

Its cold , its damp , its going to snow , its dark by 4.30pm,  theres no money ,  the country lives from one week to the next , councils are cutting back all services, theres a housing shortage, a job shortage , its overcrowded , theres too many vehicles on the roads, theres floods all over..... and we're on an Amber alert for the next murderous atrocity by the Mad Muzzies .............

....................    erm.......why did you say they are all waiting to come over from Calais ....??