New poster with some electrical q's

[Deans15]

Hi, I'm new to the forum, please excuse the essay and forgive me if this has been covered before, I have had a look around but couldn't locate the exact info I needed

I've signed up because although I have an electrical background and am familiar with domestic wiring, I'm no expert and I wanted to get some confirmation/feedback on a circuit I have planned to use in a family members chalet, he has completely gutted it and it is going to need an entirely new electrical system, and I'm trying to do it in the safest and most convenient way possible.

Basically, I will be fitting a dual rcd consumer unit to the incoming tails, aside from radial circuits for the cooker supply and shower he would like a few 2g sockets per room and a lighting circuit. Because the project is being done in stages I have ruled out a socket ring that covers the entire chalet because of having to delve back into completed rooms that have been boarded and furnished, also because of a lack of any kind of loft, I don't wish to fit junction boxes wired conventionally for his spot lighting circuits because they will later be inaccessible if there were to develop a fault, so my plan is as follows:

For basic rooms such as the lounge and bedroom where only a few sockets and a lighting circuit is required I intend to use a b32 and 2.5 flat t&e running a small ring of say 3 2g sockets, with 1.5mm flat t&e take a single 5 amp fused spur off one socket up to the dimmer for the lighting circuit. Because of the issue with lack of access for a rose/junction box I was going to join the earth and neutral inside the 1g dimmer box and obviously run the live in and out of the dimmer on the way up to a radial daisy chain of a maximum of 6 gu10 50w halogens.

What I'd like to know, is would this be acceptable practice? It allows me to keep each room totally independent and minimises the amount of cable used and keeps the circuits as simple as possible....

When it comes to the shower room there will be a b32/b40 10mm radial to the shower and a b6 with 1.5mm t&e to a double pole pullchord or wall switch outside running a light and fan, perhaps running a 3&e to the fan for run on.

The kitchen will be a ring with the same 5a spur setup for lighting as the other rooms.

So, I am open to any feedback and appreciate any criticisms of my plans, I came here for info and would like to end up doing this right I'm also unsure on the regs as far as testing goes, it's a holiday residence but I'd imagine for safety and insurance purposes it would still need certifying?

Many thanks in advance, much appreciated

Dean.

 

[Deans15]

Oh and thank you mods for moving this to the correct section, my mistake .

 

[securespark]

Run it all in MICCS. It's a bit more robust and rodent resistant. Looks beautiful too. Have all joints accessible.

Use separate circuits for lighting and power. Otherwise, if the power goes down, the lights do too, that does not comply.

Split up the circuits as much as you can, to minimise inconvenience.

Use low energy lighting where you can. It's not only cheaper to run, it runs cooler too.

Don't limit your mind to a 32A RF circuit. You could have 20A radials, and if you use MICCS, you can use 1.5.

Don't put a RFC in the kitchen. Fit dedicated radials for anything 2kW +, and a 20A general radial for the smaller stuff.

 

[Deans15]

The trouble is all the wiring materials and fittings are already bought, I did try and encourage the use of led fittings etc but seeing as the electricity is flat rate included in his ground rent the initial high cost of low energy fittings against the cheaper gu10 stuff put him against it as there would be no money saving rewards for him to reap. Seeing as there are only four rooms in the chalet, running separate lighting and sockets isn't a problem on a 17 way cu If I get some extra mcb's of the correct rating, is it advisable to run the lighting from one half of the rcd board and rings and radials from the other? I always ran lighting from the unprotected side of older cu's to stop nuisance trips from blown bulbs, at least that way if a bulb goes he won't defrost his freezer? Cheers

 

[ban-all-sheds]

I've signed up because although I have an electrical background and am familiar with domestic wiring, I'm no expert and I wanted to get some confirmation/feedback on a circuit I have planned to use in a family members chalet, he has completely gutted it and it is going to need an entirely new electrical system, and I'm trying to do it in the safest and most convenient way possible.

When you or your friend applied for Building Regulations approval what was said about the way that the work would comply with Part P?

I'm also unsure on the regs as far as testing goes, it's a holiday residence but I'd imagine for safety and insurance purposes it would still need certifying?

It will, of course, need all the pre- and post-energising tests done and an EIC issued.

You must surely know what those are and be able to do them.

 

[ban-all-sheds]

seeing as the electricity is flat rate included in his ground rent the initial high cost of low energy fittings against the cheaper gu10 stuff put him against it as there would be no money saving rewards for him to reap.

You will almost certainly find that Building Control will want a % of the lights to be low-energy, and of the type which can't even take a low efficiency lamp.

No point in ignoring this - the last thing you want is for them to refuse to issue a completion notice and have to replace the lighting.

Speak to your BCO on Monday.

 

[SimonH2]

Use separate circuits for lighting and power. Otherwise, if the power goes down, the lights do too, that does not comply.

Split up the circuits as much as you can, to minimise inconvenience.

I think you could argue that he's already split things up as much as is practical. In effect each room has it's own lighting - so a bulb blowing in one room won't take out the whole house or floor like it does in most houses. Tripping the breaker in an RFC isn't (in my experience) a common occurrence, and should be even less common when there's a room with an RFC supplying only 3 DG sockets and the lights. A light blowing is unlikely to trip a 32A MCB, and probably not a 5A fuse either - I believe he could use a 10A fuse, is there a risk of someone fitting a 13A fuse (and would that be a problem ?)

Don't forget that many installations have the lighting and power on the same RCD so subject to the same "one off, all off" problem.

One thing I'd suggest doing differently would be to use RCBOs - my experience is that tripping the RCD is far more common than tripping the MCB.

 

[Spark123]

What size supply is it?