Are there any issues with using twin and earth in conduit rather than conduit cable? other than the fact that pushing twin and earth through 20mm conduit isn't easy!

Well, you certainly won't get far pushing it -- or pushing any sort of cable through conduit ! . Pull a cable through and have someone else feed the cable in at the point of origin.

You don't mention what size of T+E cable you're thinking of putting into conduit. Nor do you mention what sort of conduit. Nor whether there are inspection elbows or boxes at all turning points or whether the conduit is installed according to spec. That all comes into the equation. On the odd tricky run it can help if the leading end of the cable has the cores not just twisted together but soldered together and the joint between that and the draw tape or string covered with heat shrink tubing or whatever. Obviously the more flexible the cable and its sheathing, the better.

I find that using a silicone spray as a lubricant helps, feeding it through the straight run, then elbows, inspection tees then on to the next straight run etc.
The lubricant I use is for UPVC guttering to ease into brackets and joints.

I don't think you have to glue it if anymore, one of the Pro's will correct if I'm wrong.

John

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