Installing In / On Concrete Floor / Ceiling.

[Lee Sparks]

Hi guys,

I have been asked to quote for the re-wire of a 4 bed semi property.

The ground floor is solid concrete and so is the ceiling ( floor of the 1st floor)

Its a 60`s ex council house.

Now the client understandably, not happy with surface mounted trucking and accessories.

They also do not want the ceilings dropped, so cant install cables that way.

So its going to be a case of a heel of a lot of chasing along the top of the walls and drop down to each accessorie.

-My question is, if i cant pull cables through the original conduit to light positions. ( all light positions staying the same)

Then what other methods can i use to get the cable to center of ceilings?

I wonder if you can chase out a little of the concrete? i have not had much experiance installing around solid floor/ceilings.

I belive the routes i shall use to get up to the other floors would be via same routes for copper piping from combi boiler.

Any advice helpfull!

Lee.

 

[Sharpend]

I don't think that chasing the ceiling is advisable may have a bearing on structural strength?

Best option is to batten and false ceiling, other than that battery stick on lights!!!!!!!!

To be honest I should think that with careful hands and plenty of lube you should be able use existing conduits with singles.

 

[ProDave]

Don't just go in and rip the old cable out. Plan it carefully and use the old cable as a draw string for the new.

 

[Blue Duck]

As others, have said use the existing conduits hopefully they aren't imperial.

If it's tight you can use 1mm 6491X singles for the lights.



Had customer where the council had rewired on the surface, She complained so much and got the neighbours involved, the council did the rest of the block drawing into the existing conduits and left hers on the surface. :lol:

 

[OnOff]

And get some of this:

http://isswww.co.uk/ideal-yellow-77-wire-pulling-lubricant-1quart-squeeze-bottle?gclid=CMiG5Zv_3sECFQEXwwodiX4A3A

 

[Adrian]

around the wall/ceiling line do not chase put up coving I did loads of council flat rewires like this 

 

[Steve3948]

As others, have said use the existing conduits hopefully they aren't imperial.

If it's tight you can use 1mm 6491X singles for the lights.



Had customer where the council had rewired on the surface, She complained so much and got the neighbours involved, the council did the rest of the block drawing into the existing conduits and left hers on the surface. :lol:

Never seen 1.0mm² 6491X 

 

[Blue Duck]

Yes your right, it's like rocking horse poo.

http://www.cordsncables.co.uk/acatalog/6491X.html

 

[Evans Electric]

The whole point of doing those jobs in conduit was to make them rewirable .   As long as everything is in the same place you should have no problem .

I'm guessing , 60's council house will be in 3/4 inch steel conduit .  As said , not sure if 6491X goes down to 1mm  but you'll be fine with 1.5mm . 

Note :-   ( If you are normally house bashing  don't fall into the trap of trying to  wire in Twin/E  6242Y  through conduit )

As Dave said , use old cable as drags ...DO NOT pull them all out in one go .    You'll probably  find no earth wire , conduit will be the earth .  ( Earth wire:-  not sure what they call it this month )

Oh  a hint .   Fixing screws will be 2BA   NOT  M4   so make sure you save them all for 2nd fix.    Plate screws will be 4BA  but can be tapped out to M4 .  

Edit :-   You might want to fit a metal C/U  ....drill it to suit the in situ conduits .

 

[kerching]

And sometimes the conduit boxes have no lugs as they were specific to one make of weird switch, so you will need these

Mk 3840 zic

Just anticipating your pain!!!!

 

[steptoe]

U do rewires on council flats with conduit,

Wire them all in t&e,  saves worrying about the integrity of the existing conduit,

Just be careful that you won't have links between sw and light in every room,

use 3 core to these lights as an extra switch wire.