Cable run

[kevinduff]

Hi

I am intending to run a spur into a new conservatory from the existing downstairs ring using a FCU to allow a couple of socket points. My problem is that its no longer acceptable to run a cable through or in a cavity wall, however is that still the case if the wall concerned is directly into the conservatory and/or the cavity has insulation.

Many thanks

Kev

 

[securespark]

You could put some conduit through the wall.

What length of cable will be in contact with the insulation?

 

[1john]

i beleive the problem with running cables in cavities is to do with supporting the cable. flexible conduit would get around that.

 

[spark1]

Are we talking about the section of cable passing through the main house cavity wall or also within the conservatory wall ?

 

[kevinduff]

Hi thanks for the reply

It has to do with water access to the cavity and the effect water and dampness would have on the cable over time.

The insulation will probably be around the 50mm or so, I realize I will need to applly the necessary insulating rating factor for the ciruit as a hole but I mainly wanted to clarify that I would not be in breach of the building regs if the extention was inspected.

 

[kevinduff]

Hi spark 1

No the cable is just going through the house cavity wall with the cable then entering the conservatory

 

[spark1]

Hi spark 1

No the cable is just going through the house cavity wall with the cable then entering the conservatory

Dont see a problem with that.....Do however ensure the new part of this extended circuit is RCD protected either at your existing fusebox or usding an RCD protected fused spur,

 

[kevinduff]

Hi Saprk1

Thanks for that, had an idea it would be ok but wasnt 100%

the existing circuit is on a 30ma rcd with a 32a circuit breaker, I will also use a 13a 1362 fuse in the FCU

 

[spark1]

Sounds like you are competant enough to do a proper job Kev......
Go for it Mate !

 

[kevinduff]

Thanks for the confidence boost

Im 56 and new to this and just past the 2382 and 2392 exams and studying for the 2391 so need the confidence boost from guys like you

Many thanks

 

[plugwash]

There are three issues with running cables in cavities

1: support, this shouldn't be an issue for small runs
2: the cavity may already be full of or later be filled with a polystyrene based material that attacks PVC cable.
3: you have to be carefull about the possibility of creating bridges that can carry moisture accross the cavity.

Personally to run a cable to a conservatory I would run a peice of conduit through the cavity with a slight slope downwards from inside to outside to ensure it didn't carry any moisture inwards.

 

[ban-all-sheds]

I'd agree with the conduit idea, if for no other reason that it'll make it easier to get the cable through.

There shouldn't be wetness in a conservatory...

If the conservatory is unconditioned, plug each end of the conduit with silicone once the cable is in.