Hello and project question?

[peter s]

Hi there
To start with, I am not an electrician but I hope that you are willing to help?, I am currently fitting out a shell of a room, i.e battens, insulation, sockets, plasterboard etc. Before I insulate I need to lay the electric cables for both sockets and lights, the room has not had electricity in it previously (just laying the cables, I will be getting an electrician in to do the actual connecting), the sockets are simple and I understand but I am unsure as to which method I should cable the lights, as I understand it can be either Loop at Light or Loop at Switch, are there any benefits to either or do the regs now require a particular method?
Hope you can help?
Peter s

 

[Midwest]

Hi Peter, welcome to the forum. In answer to your question, 'Loop' at the light or switch will really depend on what sort of luminaires you intend to install or the nature of the installation.

I note you are not an electrician, but intend to install the cables, and get an electrician in to connect. If you asked me to do this, as an electrician I would decline. Being responsible for the final connection, I would be taking on some of the responsibility of the correct installation of the cabling.

Before circuits are energised, they need inspection & testing, using appropriate test equipment.

I would suggest you rethink your project, and employ the services of a competent electrician.

 

[Pete999]

Hi Peter, lots of things to take into account:
How are you intending to feed the lights and sockets?
You need to understand that running cable in insulation may need some sizing calculations.
What type and size of cable are you intending to use?
Lastly I doubt very much if any decent Electrician would undertake connection, testing and certification of an installation he/she has not actually designed and installed, sorry to sound so negative, but you admitted you are not an Electrician, your best bet would be to employ one from the outset of your project, you could watch and learn from the experience.

 

[Paul228]

Get hold of a local sparky ( use the right channels and not a mate of a mate down the pub).
Tell him/ her what you are proposing and want to do the first fix yourself to save time and coin.

They will charge you, but will tell you what you need to do and he/ she will need you to call them back to check progress before you cover it all up in nice new Plasterboard.
Then he/she will come back and test/ make off all termination and do the final test.
Don't just chuck cables in as you may find most sparkles will walk away or get you to re do the cable runs.

Good luck

 

[peter s]

Thanks for getting back so promptly guys and I completely understand about an electrician wanting to be involved throughout and will involve one before I plasterboard so that they can see exactly how I have routed the cables. I have used a simple radial circuit for the 4 double sockets 2.5mm cable, the insulation is rockwool not Celotex, the lighting (1.5mm) will be 2 lights off a 2 gang switch (1 fluorescent 1 standard) and 2 lights (standard) off a 1 gang switch, the room is in a barn and I intend to have a separate CU in the barn for this (other rooms to be added when I can afford to do the work). National grid have upgraded our house supply from 60 amp to 100 amp so there is adequate supply.
Throwing out a question like this with you guys not having any background of the 'bigger picture' will understandably cause you to be reluctant to give info, perhaps I should have just asked what the difference between LTL and LTS was and which one is most commonly used now?, I am not trying to circumvent the system I just have to keep costs down or the project won't happen but it has to for reasons which I don't want to go into.
Anyway I hope someone will be able to help?
Many thanks
Peter S

 

[Paul228]

Are you using any form of mechanical protection for the cable runs?
I'd also suggest you get a local sparky involved so he/ she can go over your intended routes. It sounds simple but the method of installation is the biggest factor on what cable sizes to use.
It could be your barn is only 10m sq, but it could also be 100m sq.
Get someone in as mistakes at first fix can cost a few hundred to fix at the final stage.

 

[Andy-1960]

4 double sockets on a 2.5mm radial?? What size breaker would be feeding this?

 

[Ian1981]

4 double sockets on a 2.5mm radial?? What size breaker would be feeding this?

20amp hopefully tho I hope the installation methods used allow for this.

 

[buzzlightyear]

some times to much information can be dangerous.

 

[Wilko]

... they can see exactly how I have routed the cables. I have used a simple radial circuit for the 4 double sockets 2.5mm cable, the insulation is rockwool ... Peter S

Hi Peter,
The installation method is very important here. Using Method 103 the 2.5mm is rated for only 13.5A - no good at all. A small change to Method 102 and its 21.5A. But you can't do that afterwards, which is why on-site advice from the Electrician is so important ...

 

[buzzlightyear]

is the sparky going to sign off the say job, your are doing re design ?
constructed &test, in my book I would not do it.

 

[The Ghost]

As the OP said he is going do it and show the electrician. He has his own way of doing things.

 

[Pete999]

As the OP said he is going do it and show the electrician. He has his own way of doing things.

Yeah right

 

[peter s]

Thanks for the feedback, I'll get back with an outcome once an electrician has had a look.
Many thanks

 

[Octopus]

I intend to have a separate CU in the barn for this (other rooms to be added when I can afford to do the work). National grid have upgraded our house supply from 60 amp to 100 amp so there is adequate supply.

Now you are talking about adding a separate CU - you should really get a local spark involved..... then there is planning and Part P.....