Expanding Foam around electric cables

[mfarrow]

the person who made that rule obviously hadn't seen my collection of nails and drills

I've yet to find any situation where I've needed a 4" screw in the ceiling . Mind you, I've yet to find a situation where I've the needed to hang anything from the ceiling without having the floorboards up anyway.

 

[PrenticeBoyofDerry]

Don't the regulations about burying cables and drilling joists with a 50mm. rule automatically and obviously mean screws and nails longer than 50mm. should not be used?

That is what you would logically think, but a man with many nails and drill bits much longer than that, should be allowed simply to crack on!

 

[JohnW2]

Don't the regulations about burying cables and drilling joists with a 50mm. rule automatically and obviously mean screws and nails longer than 50mm. should not be used?

Perhaps they should, but I'm not sure that all users of screws and nails have been informed about that!

To be serious, screws and nails which could penetrate deeper than 50mm are probably not often used in walls and ceilings, but it's the drills which are potentially much more of a hazard. At the sort of diameter we're talking about, most would be well over 50mm long ('exposed length') and I'm sure we are all familiar with the drill that suddenly 'goes in' much further than we had intended!

Kind Regards, John

 

[Iggifer]

Somewhat back on track, I've seen expanding foam used around an entry for a bunch of PVC SWA cables (and it wasnt a tidy application of foam) which had clearly been in place for a few years and had had no effect on the PVC

 

[JohnW2]

Somewhat back on track, I've seen expanding foam used around an entry for a bunch of PVC SWA cables (and it wasnt a tidy application of foam) which had clearly been in place for a few years and had had no effect on the PVC

As I said right at the start of this thread, my understanding has always been that 'standard' expanding polurethane foam is harmless to PVC cables. A number of years ago (probably about 15) I asked two or three manufacturers of foam about this, and they all confirmed that it is OK. I've certainly had PVC cables surrounded by PU foam for well over a decade, and have seen no effects.

Of course, burying even a short length of a cable in any sort of foam theoretically has an impact on the CCC.

Kind Regards, John