Confused with so many rules

Anya32 · Jul 3, 2021

Hi

I have had three electricians quote to wire my new kitchen which is currently a shell. The thing I don't understand is that they
seem to differ in their approach to the electrical rules, for instance, two are happy to place oven and hob isolation switches in a cupboard and one will not. One has suggested that he has to fix metal back boxes without plastic plugs but instead use expensive fixings. One has said that he cant run cables in the 150mm deep stud wall, very confusing!

brianmoooore · Jul 3, 2021

We must have started writing at almost the exact same time, but my post is shorter, so I got in first!

Dartlec · Jul 3, 2021

brianmoooore said:
150mm figures in the definition of several of the 'safe zones', but there is NOT a safe zone running horizontally up to 150mm from the floor.
If the cable is run in the middle of 150mm thick wall, then it doesn't need to in a 'safe zone', as it is considered (not by me) to be deep enough to be safe anyway, but if the wall is insulation filled it severely derates the current carrying capacity of the cable. The cable can be increased in size to counter this, of course, but it's best to avoid running a cable totally surrounded by insulation if avoidable.
The non plastic wall plugs for boxes is one of the most ridiculous things I've ever read on here. Total nonsense, told by someone who is either a crook or clueless.

Let's not rule out both!

Anya32 · Jul 3, 2021

Thanks for the clarification guys. Much appreciated x

Pete999 · Jul 4, 2021

Anya32 said:
Thank you all for finding the time to give me advice, it's much appreciated.
To answer your questions, the metal back boxes are into masonry and it struck me as odd that there was a rule about using plastic plugs, I did ask for an explanation and that was that in a fire they would melt??? The 150mm stud wall will have acoustic Rockwool in the cavity but the electrician said that he could run the cables within 150mm of the floor, so you can see why I'm confused.
As suggested, I think I will get yet another quote.

Anya32 to be honest you need to get an Electrician with lots of experience, not some chancer that hasn't any common sense, that is, as already mentioned a crook trying to up the price, baffling someone "no criticism of yourself" that has very little or no experience of electrical installation work, out of interest what fixings did this Herbert recommend using to fix the boxes to the wall??, good luck, post your location, a member may be able to help you out.