Polystyrene Insulation And Electrical Cables

[skam]

I have just had my kitchen done, the electrician fitted a tube ceiling light and took the cables for this through the roof, after which the builder fitted which i  believe to be polystyrene block insulation in the roof with the electrical cables, everything has now been plastered and I am worried if the insulation is safe with these cables. Any advice would be appreciated. 

Qualified electricians only please

 

[SLIPSHOD & SLAPDASH]

This is not correct as the polystyrene leeches the polymer from pvc and it becomes brittle . I have a pic taken last week of one i found

 

[skam]

Thanks, not sure what's best to do, is there any way to resolve this without having to break the new plastered ceiling?

Thanks, not sure what is best to do, is there any way of resolving this without having to disrupt the newly plastered ceiling? How dangerous is it if the pvc becomes brittle?

 

[SLIPSHOD & SLAPDASH]

Here is the pic, cant say how long the lighting cable was there, but it does take a long time to affect it



If the cable is not disturbed it will probably  pass insulation resistance checks for a long long time, however the official answer is its not correct.

 

[kerching]

I had a pvc flex running across the back of an ACU ceiling cassette. It ran over the styrene insulation and when i got to it the flex was "melted" into the polystyrene

Must have been there about 10 years

Is yours polystyrene or Kingspan type Urea Formaldehyde type stuff

 

[NozSpark]

Heres one I found a few years ago

http://i222.photobucket.com/albums/dd101/nozspark/Picture%203568128.jpg

 

[binky]

A few years ago i wrapped a bit of off cut cable around a bock of polystyrene and left it in the van for over a year, and it did buggerall. Polystyrene beads are a different matter, they continuosly collapse onto the sheath to constantly leach the plasticiser.

If the cables are under the polystyrene i would be less concerned, if they are sat on top and loose to melt into insulation, that's a different ball game. But the general consesus is you don't do it!

 

[Evans Electric]

I'd guess , because its a modern install, the material would be Celatex or similar not polystyrene .  Its your builder's responsibility to ensure he uses the correct stuff ,  ( And the Porcine fraternity will take to the air)