Can I use cable instead of flex in my house wiring?

Aside from pendant drops to lampholders, you are unlikely to need any flex in a basic rewire...

Do you mean cable?

Cable is what you do wire a house in... flex is used for connections between appliances and their plug typically.

You need 1.0 or 1.5mm^2 T&E for lighting circuits, and typically 2.5mm^2 T&E for socket circuits...

wiki.diyfaq.org.uk/index.php?title=Cables

Bet that surprised them!

Obviously you don't know what you're doing, or at least don't make yourself clear.

Stranded figure eight wire for the lights, but use proper solid copper core bell wire for the sockets. Tape-join a foot or so of the appropriate size twin and earth at each accessory, in case BC inspector comes.

sorry, yes, i got the words back to front! will try again... [g]

sorry, i got the words back to front! will try again... [g]

The different wires are colour coded. Try not to get them back to front.

Bill

So the question was "I have lots of flex, can I use that instead of cable?"

In which case that's easy:

No.

Dangerous advise, he might do it without realizing thr sarcasm.

Enquiring minds ask "Do the regs actually state that?" I would expect an installation done in flex to fail Building Control but it would be interesting to know which bit of the regs it breaks. After all you could use pyro, singles in conduit, SWA etc.

Assuming that the CSA's are correct for the circuit it's been used for(*) and that it has the requisite layers of insulation (ie two) the only other thing I can think flex will fail on is individual core colours. Ideally every end would have a bootlace ferrule fitted where they connect to an accessory.

(*) Taking into account the stranded rather than solid nature of the conductor.

"512.9.1 .... flexible cables used for fixed wiring shall be of the heavy duty type unless the risk of damage .....is low .... or protection against mechanical damage is provided. BS7540 describes light, normal and hevy duty types."

So, I'd read that as flex is acceptable, if it is both well protected, during installation and service, and of course meets the current carrying capacity.

Why anyone would use it is another matter, flex is more expensive than T+E.

That's the killer really... "old lighting cable[flex]" is not going to be of adequate CSA in the first place. (and most flex you find is common use is 1.5mm^2 or less - often less). So while you could construct a lighting circuit out of it, you would have difficulty meeting the needs of a general purpose power circuit unless you are going for lots of small radials.

Since harmonisation, the core colours should be ok.

The old flex i have is from stage lighting, so its probably fat enough.

I dont think I'll bury any under the floorboards, but maybe use it inthe attic for lights- it's cheaper than grey cable because its free! [g]

On Saturday 23 March 2013 11:47 A.Lee wrote in uk.d-i-y:

It's an interesting point. I have some GX53 lamp fittings on 3 bay ceilings because they are low profile.

There is conduit for each one leading to the loft space. The GX53 fittings have pre fitted flex.

I plan to extend the flex so that it will feed all the way through the conduit into a joint box in the attic and into T+E. Flex is heavy 1.5mm2 to match the fixed wiring.

I would rate the risk of damage as low (not an attic area you can walk in - right near the eaves) but I'm glad you raised that point. I might complete the conduit to joint box in flexi conduit - only a couple more feet.

I do have the 12V final leg on a cluster of bathroom lamps run in heavy flex

- only a couple of meters and again, no real risk of damage - clipped halfway up the side of an 8" joist.

It's been done.

It would work on a 3A fuse with an rcd. But not a good plan!

NT

So a floor void, that requires access by the use of tool, would satisfy the protection from damage?

Really being devils advocate to see how well the regs have been thought through.

Not if you have loads of 2nd user flex for free. B-)

I'd still not use flex for fixed wiring though, the argument with the inspector just isn't worth it for a start.

But do you also have the required conduit etc and the time to install it all as well to make the "free" flex usable?

The investment of time installing it will far exceed the cost of a reel of cable.

OK, I will only use the old stage lighting flex for: plugs to accessories, hanging pendant lights, and extension leads.

As long as they have a 13amp plug and fuse is it OK to clip extension leads to roof beams, and to run them through walls and hidden under floorboards? [g]