wiring a new garage

we are having a new garage built and wanting power in it as the drive is tarmac i don't wish to dig this up but I am thinking of laying armour cable underground then up the bungalow wall and into the loft can the armour cable be changed to standard cable once in the loft and onto the RCB/MCBs [/code]

Yes - terminate the SWA in a metal adaptable box and join it to normal T/E.

How long is the run?

What size of SWA will you be using?

Do you have a PME supply?

Thanks for your reply, the run is approx 15mtrs, we have not purchased the SWA as yet, do you have a best suggestion for this, the garage will probably only have a couple of double sockets and a strip light.

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Always leave room for expansion!!

Fit as big a cable as you can afford.

If your main supply is not PME, consider at least 4mm 3 core SWA, and use one of the cores as earth,m in addition to the armour, which must be securely glanded at both ends.. At the house cover with 32A trip, and in the garage have small consumer unit, with RCD, 6A lighting breaker, and 16A breaker for a 2.5mm radial feed to a hand-full of sockets. If there is any risk of this not being enough for unknown future demand, then 6 or 10mm are the next largest options, and while probably overkill, some will recommend them as future proofing, depends if you are a power tool freak, and worried about the lights dimming a bit as you and yours use the plasma cutter and arc welding equipment together...
What I have recommended is for lights plus a l bar fire, and either a lawnmower or electric drill, but not both at once type of user.
If your supply is PME, you would be well advidsed to install a local earth spike at the garage, and only use the house earth to protect the cable armour on its way out there.

regards M.

PS If this is a new circuit, and all works started this year, then the dreaded part P bites, and strictly to stay within the new rules, you should notify the local building control office, who will charge to infect your work.
(or employ a sparks belonging to a self certification scheme at vast cost.)

mapj1 said:

PS If this is a new circuit, and all works started this year, then the dreaded part P bites, and strictly to stay within the new rules, you should notify the local building control office, who will charge to infect your work.

Click to expand...

Was that a typo map ?

Scoby, you might think that, you might very well think that, I could not possibly comment.
So what do you think ?
regards M.

PS I suspect after the hooo-haa of the first months has settled it will be policed with all the vigour that notification for building regs part L is policed now, i.e. very little vigour indeed, unless the job is done so badly, that someone formally complains about it. Given that we can't eleiminate unregistered gas installers *, I think people doing the job properly but failing to notify, will get no more than a warning, and possibly the cost of a PIR type check-up when the house is sold, if an eagle eyed solicitor insists on all papers being present.
* who may, or may not, really pose any more threat than registered ones.... but thats another discussion