Wow... its all changed.... Advice on err.. a few things!

[Steve2381]

Bit embarrassed to be asking this. Its been a bad year.

Hi all. Back in January I did my City and Guilds 17[SUP]th[/SUP] Edition Full 2382-12 IET level 3. Just to brush up, as I have been out of sparking for about 6/7 years (sparky for 12 years before that)
Was hoping to do 2391 - but had an accident that has trashed most of this year.

Anyway... No job (North East UK - its bad here), pretty bad financial situation and I have been offered a small extension to wire. I basically cannot afford to turn this down.

So - first issue is the pain-in-the-arse Part P malarky. I would like to get myself up and running properly, so I planned to use this job as an 'inspection' job when I register with someone for Part P certification.
I am stuck in that 'getting started' loop of no back portfolio of work, but unable to get any work due to no Part P.

If registering doesn't work, then I will have to either ask the building inspector to arrange to have it checked by their approved guy - or find my own sparky to issue the Part P after a test etc.

This is a new extension (to an old house), so does the Part M compliance of 450mm to bottom of socket / 1200mm to top of switch / 350mm in from a corner apply?

Having been out of the loop - its going to take a little time to get back into my stride.

I think there are things like 25% of the lighting must be low energy? (not an issue - she wants all LED)

Anything else I should look out for regards regs I may have missed? The 2382-12 didn't really bring up anything I didn't already know.

Thanks guys

 

[RyanCheetham]

Socket heights for part m are for newbuild. For an extension or rewire you can place them at any height you want

 

[Steve2381]

I thought that was the case. Better to check than have to re-cut all the boxes in again!

What is the deal with cables in the plaster these days then? I was watching a sparky on an extension not far from me and the wires were just getting buried in the plaster - no metal capping or anything. I thought there needed to be mechanical protection from plastering trowels etc?

If I did use metal capping, then I would assume it needs connecting to the metal box (and then the box tagged)?

However, if the walls are dot 'n' dabbed - then I assume simply clipping is fine.

 

[mackers]

if your gonna regester part p ring building control and explain the situation ,anytime ive delt with building control ther usally pritty cool as long as your striaght with them all they want is a good job .
been in same situation years back main man came to see me on site once he realisied i was 2391 he just said once your sorted send us the cert! simples

 

[GLENNSPARK]

I thought that was the case. Better to check than have to re-cut all the boxes in again!

What is the deal with cables in the plaster these days then? I was watching a sparky on an extension not far from me and the wires were just getting buried in the plaster - no metal capping or anything. I thought there needed to be mechanical protection from plastering trowels etc?

If I did use metal capping, then I would assume it needs connecting to the metal box (and then the box tagged)?

However, if the walls are dot 'n' dabbed - then I assume simply clipping is fine.

metal/PVC channel aint `mechanical protection` fella...
several options here....if less than 50mm in a wall chase.....then additional protection by means or RCD no greater than 30mA.....or run em in an earthed metalic containment (conny).....
i take it the earthing arrangements are TN?...

 

[Steve2381]

Yep. Tn earthing. So if its behind plasterboard then (dot 'n' dab).... every bloody wire has to be chased in?... regs gone mad again then.
I know capping isn't mechanical protection, I thought it was purely to stop the plasterers trowel damaging the cables. (err... same thing?)
All circuits will be 30mA RCD

 

[Lindsayandson]

metal/PVC channel aint `mechanical protection` fella...
several options here....if less than 50mm in a wall chase.....then additional protection by means or RCD no greater than 30mA.....or run em in an earthed metalic containment (conny).....
i take it the earthing arrangements are TN?...

Can I ask a daft laddie question? If earthed metal channel does not provide mechanical protection, what is its purpose?

 

[Steve2381]

I thought (don't have my regs to hand)... if the cable is under 50mm from the surface, then 30mA RCD on each circuit is sufficient protection? Or am I wrong.
Then the capping would surely just be protection from Mr Heavy handed plasterer.

 

[Simlec]

Can I ask a daft laddie question? If earthed metal channel does not provide mechanical protection, what is its purpose?

Protection from a plasters trowel

 

[Geoffsd]

Can I ask a daft laddie question? If earthed metal channel does not provide mechanical protection, what is its purpose?

Just holds it in place - easier for plastering.

 

[Geoffsd]

I thought (don't have my regs to hand)... if the cable is under 50mm from the surface, then 30mA RCD on each circuit is sufficient protection?

Only if in prescribed 'safe' zones.
Elsewhere, if you need to, it will require other protection.

Then the capping would surely just be protection from Mr Heavy handed plasterer.

Yes. Also, plastic can be used.

 

[brucelee]

yes if cables less than 50mm then RCD or use mechanical protection such as earthed conduit so easier to clip direct and use 30mA RCD the capping is jsut to protect from plasterers trowel upto you wether to use it
or should i say upto the customer you could just use PVC channel, oval conduit or none
if your going to register with a scheme then they will want to see at least 1 major job such as rewire or ccu change with earthing and bonding present
you could contact them and ask would a extension be acceptable for them to see

 

[brucelee]

as for energy efficiency of lighting its now 75% but you can use a fitting that will accept energy efficient light bulbs as well as ordinary GLS lamps such as pendents etc

the Elecys guide to building regs would be helpful to you

 

[Steve2381]

Thanks all.
OK... so I am on track. New ccu for the extension, metal capping (because I have a load of it in the store) and RCCO's on all circuits anyway. All zones are safe.
The extension is basically a living room and study. Nothing special.
The house is pretty much up to scratch - I wired it just before I packed up sparking. Earth bonding etc is all in place.

Final question/s ... honest.
Do you have to provide fire hoods on led downlighters?
The client has a length of 25mm 3 core SWA he wants to use for the submain to the extension. But its old red/black/yellow. He wants to sleeve it to the new colours/regs, but I don't think you are allowed to do that.
There is a submain by the way, as they plan to add a kitchen at a later date, and the fuseboard is not easy to get to.
I thought you had to install only the new harmonised colours now. That would have only been acceptable if it was already installed a long while back(eg Underground).

 

[malcolmsanford]

Thanks all.
OK... so I am on track. New ccu for the extension, metal capping (because I have a load of it in the store) and RCCO's on all circuits anyway. All zones are safe.
The extension is basically a living room and study. Nothing special.
The house is pretty much up to scratch - I wired it just before I packed up sparking. Earth bonding etc is all in place. If you rewired this place 10+ yrs ago you may need to check if the bonding needs upgrading for the new regulations

Final question/s ... honest.
Do you have to provide fire hoods on led downlighters? No there is no need to have fire hoods on downlighters in a single dwelling, but they are good practice
The client has a length of 25mm 3 core SWA he wants to use for the submain to the extension. But its old red/black/yellow. He wants to sleeve it to the new colours/regs, but I don't think you are allowed to do that. No there is noting wrong in using the old cable, as long as you sleeve the terminations to the new colours. But to be honest if your going to use this job as your assessment I would seriously think about using another SWA that as the new colours

As it is a sub main I assume that the cable is 6mm+. SWA cable that size is not something that is normally "hanging around" in a domestic home, so I would be wary of it. If you do use it make sure that you test it thoroughly

There is a submain by the way, as they plan to add a kitchen at a later date, and the fuseboard is not easy to get to.
I thought you had to install only the new harmonised colours now. That would have only been acceptable if it was already installed a long while back(eg Underground).

.............................................................

 

[Steve2381]

The SWA is 16mm 3 core. I may try and get a new T&E 16mm + separate CPC through internally however.
The old house is bonded within an inch of its life. I am going to upgrade the old board anyway, as it could do with a tidy (people have fiddled since I was here last)
Fire hoods - I was going to anyway, I think they are worth it.
Thanks all

 

[Steve2381]

I thought it best to keep this on the same 'few questions' thread...

Smoke detectors. Existing house has 3x interlinked mains fed smokes, but there is no way I will ever be able to extend them on (no way to get a 3 core there).

So, firstly... I am right in thinking that the new extension is going to need a smoke detector, connected to the existing system (can't be stand alone).

Secondly, they plan kitchen in one of the rooms at a later date, so I am guessing that should have a heat sensor in it linked as well.

Steve

 

[Stroppy]

Aico do radio linked alarms, so they only need mains power and communiate with the others via a radio link. Problem solved

Mains Powered - RadioLINK AlarmsAico - Fire & CO Detection & Fire Protection Specialist

Whether they will communicate with the existing alarms is a different matter, unless you are prepared to change the existing ones for Aico's as well.