protecting cable through wall for outside lights

[Guest112]

Been installing outside lights recently and drilling a 25mm hole to fit a 20mm pipe to the outside light and sealing it etc, Is it acceptable say to drill a 10mm hole to get an fp200 through the wall and seal it or is there a regulation saying it needs protection through the wall??

The only way the cable could get damaged really is if something fell down the cavity and hit the cable which is very unlikely, is this method ok guys??? thanks

 

[stuart569]

Nope, The new stuff came in around the mid 90's and still called polystyrene. Mainly comes in bag's of balls, not in sheets, ... that is polyurethane. They just changed the chemical make-up slightly to take away the plasticising affect on PVC cables and building materials... But, there is still a hell of a lot of the older stuff about to be aware and cautious about!!!

I stand corrected!It was the sheets that were the issue with sausage agent I worked with.Yep went to see a job with gaffer a couple years agpened a floor board to find bare cores all sitting nicely just waiting to be disturbed.Amazing to see

 

[i=p/u]

i installed power for a velux window, and put the fused spur in opposite side of where cable was... looked at the window upside down when was in box on floor, but the cable was long enough to just chase it into polystyrene ... then i seen that new polystyrene didnt have these properties anymore, and was over the moon... oj glenspark im sure you wont run cables under a floorwith caping over

 

[stuart569]

That takes buried in insulation to a new level!

 

[Engineer54]

You could well be right, there were a few earlier attempts at reducing the chemical that was responsible for the plasticising affect. One of them caused the ''sticking together'' of the balls thus reducing the insulation level. Most still affected PVC to some level, in the long term though. It wasn't until around the mid 90's that they came up with the present stuff, that was guaranteed not to have any affect on PVC compounds...

 

[GLENNSPARK]

yeah well i have no probs blaming my boss for this as it was he who said to do it.....cant argue with that can i?....i will admit it was a tricky one though this install....you couldn`t chase it into the wall as the client wasn`t having it......

 

[i=p/u]

some wont.. thats when i tell them get to france, im going chat about electrics , get back to me if you wanna listen

 

[MarkieSparkie]

Most "green energy" cavity wall insulation installers are using Blown Flocked Paper in preference to polystyrene pellets these days. Allegedly it traps twice as much air relative to poly beads.

 

[Guest112]

thanks for the responses guys reason i asked was two engineers at my firm couldnt think of a reg stating you couldnt do the mentioned method from my OP i had a look couldnt find one so just a bit of peace of mind tbh cheers!!

 

[Engineer54]

thanks for the responses guys reason i asked was two engineers at my firm couldnt think of a reg stating you couldnt do the mentioned method from my OP i had a look couldnt find one so just a bit of peace of mind tbh cheers!!

Not a particually a good material in damp prone conditions, certainly wouldn't trust it in cavity walls. Fine for internal insulation needs.... I think i'd stick to the poly stuff myself!! lol!!!