Just a thought...

[jimmymac]

Good afternoon people,

I've had a thought (i dont have many), my friend has recently had his loft insulated for free, this is normal practice in my area at the moment due to a goverment scheme. The contractor has laid insulation which is 12 inch or 300 mm thick, surely i would be correct in thinking this changes the installation method of the cable from method C to method 101?

If so, would the contractor be responsible if the cable over heated or am i getting too deep and i need to take a holiday?

This is only a theoretical question as it is only a small circuit so i think it will still comply but i am interested in your views on the matter......

thanks

jimmy

 

[Moses]

these contractors should be rolled up in insulation and locked in the attic on a hot summer's day.

Tele if you insulate them before locking them in then they won't feel the heat?

 

[jimmymac]

Would they be legally allowed to plead ignorance? After all we are expected to know many aspects of the building regs that may not have a direct bearing on us but if we did something to contravene them and something did go horribly wrong would the guy in the wig and funny clothes accept "Sorry your honour, I didn't know that"

A very good point Trev but what training would somebody that rolls out insulation have?? If you ask one of these contractors if he had considered the ccc of the cables he is covering what kind of reply do you think you'd get?? Probably something along the lines of "thats your job, not mine"

 

[KFH]

I am working on a job where the stuffers came just before me on one of these free install schemes. They have made a good job of the stuffing but there was 100mm of insulation already in place with the cables run everywhere over the top, they have then put their 170mm on top. I have to move all the stuffing to try and find the cables I need to join to, some of them need replacement due to the attention of mice. Only 3ft headroom at the apex! Lovely job :mad2:

 

[Philpot]

It does make me wonder if all the rating factors make much sense. They are based on good science but don't they just overcomplicate the situation. Maybe we should have CCC's that assume that insulation, and maybe some other variables, will be present. On the one hand we have to deal with the situation as we find if but it is almost certain that insulation will be present at some time in the future in a cable run. This doesn't help existing installations but it would future-proof any new installation. To expect professional or amateur insulation installers to be aware of the electrical and thermal characteristics of electrical insulation materials is just plane daft.
It is rare to have to go much more that one cable size up so we could have, like we did in the bad old days, have a cable rating table. When these methods first came out it was easy to calculate a cable size that would not fit in the terminals of a 13Amp socket. Agent provocateur.

Philpot

 

[Smudge]

thats why you should use the switch as a junction box, but that's another thread!

That's brave bringing up that debate again!!!!

 

[jimmymac]

I am working on a job where the stuffers came just before me on one of these free install schemes. They have made a good job of the stuffing but there was 100mm of insulation already in place with the cables run everywhere over the top, they have then put their 170mm on top. I have to move all the stuffing to try and find the cables I need to join to, some of them need replacement due to the attention of mice. Only 3ft headroom at the apex! Lovely job :mad2:

To use a line from Monty Python's 'Meaning of Life'...... "You lucky, lucky, lucky b*****d"