Cable size for future extension.

[Chri5]

Why use 150mm duct ?

A continous 1 piece end to end of poly => 40mm would do, this could then surface at either end and simply be stopped with a plug.

http://www.draindepot.co.uk/index.asp?m=&cat=3&scat=13&gclid=CNSzkqee66MCFUH92AodK2XdJQ

 

[Deluks]

I already have a quantity of this duct which will be used to send a 10mm4c to the garage, I was simply going to 'borrow' this to house a second cable left in situ were an extension to be added. Hence the need to 'break in' to the duct to access the spare cable.

 

[ban-all-sheds]

What about when the cable is removed from the duct to feed the new extension. where is the protection between duct and the surface.

You install the ducting with a radiused bend in it to bring it to the surface.

 

[Deluks]

What about when the cable is removed from the duct to feed the new extension. where is the protection between duct and the surface.

You install the ducting with a radiused bend in it to bring it to the surface.

OK, so say I've just built an extension. If I dig down, locate the duct and cut a hole in it, pull out the cable and insert a length of smaller flexi conduit this will enable me to safely tee off from the main duct and into the new structure, and this will be legal and above board using T&E, even if the ducting runs partially outside, under a patio.



When I say 'me' I mean an electrician. Or me working under the supervision of an electrician.

 

[ban-all-sheds]

You've lost me - did I miss or not properly read an earlier post?

Why would you cut into the ducting? I thought you were running it to where you'd have a CU if you built an extension?

 

[Deluks]

You've lost me - did I miss or not properly read an earlier post?

Apparently so.
I am running ducting to the garage at the end of the garden. This will run under the existing patio. I thought while the floor and patio were up, it would be wise to include an additional cable in the duct, in case an extension was built on the back of the house in the future. It has been considered but no definite plans as yet.

All my questions have been about this additional cable.

 

[ban-all-sheds]

Put a 2nd run of ducting in alongside the garage run, don't dig up and cut into one going somewhere else.